Document and Entity Information	12 Months Ended
Document and Entity Information	Dec. 31, 2015 shares
Document Information [Line Items]
Document Type	20-F
Amendment Flag	false
Document Period End Date	Dec. 31, 2015
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	FY
Trading Symbol	ICLR
Entity Registrant Name	ICON PLC
Entity Central Index Key	0001060955
Current Fiscal Year End Date	--12-31
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding	54,958,912

Consolidated Balance Sheets - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Current Assets:
Cash and cash equivalents	$ 103,911	$ 118,900
Short term investments - available for sale (Note 3)	85,990	97,100
Accounts receivable, net	409,165	370,956
Unbilled revenue	173,649	146,163
Other receivables	30,935	17,491
Deferred tax asset (Note 13)		24,716
Prepayments and other current assets	37,822	28,465
Income taxes receivable (Note 13)	22,961	15,716
Total current assets	864,433	819,507
Other Assets:
Property, plant and equipment, net (Note 6)	150,218	148,185
Goodwill (Note 4)	588,434	463,324
Non-current other assets	11,591	11,583
Non-current income taxes receivable (Note 13)	11,362	15,060
Non-current deferred tax asset (Note 13)	26,738	21,472
Intangible assets (Note 5)	66,127	49,719
Total Assets	1,718,903	1,528,850
Current Liabilities:
Accounts payable	7,021	2,793
Payments on account	318,697	280,097
Other liabilities (Note 7)	231,879	251,091
Deferred tax liability (Note 13)		229
Income taxes payable (Note 13)	14,203	4,149
Total current liabilities	571,800	538,359
Other Liabilities:
Non-current bank credit lines and loan facilities (Note 20)	350,000
Non-current other liabilities (Note 8)	12,224	13,179
Non-current government grants (Note 11)	959	1,116
Non-current income taxes payable (Note 13)	16,180	12,389
Non-current deferred tax liability (Note 13)	4,644	13,601
Shareholders' Equity:
Ordinary shares, par value 6 euro cents per share; 100,000,000 shares authorized, (Note 12) 54,958,912 shares issued and outstanding at December 31, 2015 and 60,106,780 shares issued and outstanding at December 31, 2014.	4,679	5,037
Additional paid-in capital	383,395	327,234
Capital redemption reserve (Note 12 (a))	715	305
Accumulated other comprehensive income (Note 19)	(61,636)	(37,555)
Retained earnings	435,943	655,185
Total Shareholders' Equity	763,096	950,206
Total Liabilities and Shareholders' Equity	$ 1,718,903	$ 1,528,850

Consolidated Balance Sheets (Parenthetical) - € / shares	Dec. 31, 2015	Dec. 31, 2014
Ordinary shares, par value	€ 0.06	€ 0.06
Ordinary shares, shares authorized	100,000,000	100,000,000
Ordinary shares, shares issued	54,958,912	60,106,780
Ordinary shares, shares outstanding	54,958,912	60,106,780

Consolidated Statements of Operations - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Revenue:
Gross revenue	$ 2,161,618	$ 2,030,286	$ 1,784,345
Reimbursable expenses	(586,640)	(526,970)	(448,287)
Net revenue	1,574,978	1,503,316	1,336,058
Costs and expenses:
Direct costs	908,979	903,167	845,413
Selling, general and administrative	326,786	336,461	313,931
Depreciation and amortization	57,677	52,542	46,514
Restructuring and other items, net (Note 14)		8,796	9,033
Total costs and expenses	1,293,442	1,300,966	1,214,891
Income from operations	281,536	202,350	121,167
Interest income	1,306	1,151	986
Interest expense	(3,992)	(785)	(1,288)
Income before provision for income taxes	278,850	202,716	120,865
Provision for income taxes (Note 13)	(39,311)	(30,248)	(18,053)
Net income	$ 239,539	$ 172,468	$ 102,812
Net income per ordinary share:
Basic	$ 4.08	$ 2.80	$ 1.69
Diluted	$ 3.97	$ 2.73	$ 1.65
Weighted average number of ordinary shares outstanding:
Basic (Note 2 (u))	58,746,935	61,496,115	60,907,274
Diluted (Note 2 (u))	60,290,033	63,131,417	62,253,251

Consolidated Statements Of Comprehensive Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Net income	$ 239,539	$ 172,468	$ 102,812
Currency translation adjustment	(35,105)	(45,038)	10,725
Currency impact of long-term funding	7,342	9,806	(1,046)
Tax on currency impact of long term funding	(3,574)	(178)	(87)
Unrealized capital (loss)/gain - investments	(54)	20	(239)
Actuarial gain/(loss) on defined benefit pension plan	2,693	(4,125)	1,383
Gain on interest rate hedge	4,617
Total comprehensive income	$ 215,458	$ 132,953	$ 113,548

- Definition

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

+ References + Details

Consolidated Statements of Shareholders' Equity and Comprehensive Income - USD ($) $ in Thousands	Total	Ordinary Shares	Additional Paid-in Capital	Capital Redemption Reserve	Accumulated Other Comprehensive Income	Retained Earnings
Balance (in shares) at Dec. 31, 2012		60,287,498
Balance at Dec. 31, 2012	$ 754,575	$ 5,067	$ 237,217	$ 100	$ (8,776)	$ 520,967
Comprehensive Income:
Net income	102,812					102,812
Currency translation adjustment	10,725				10,725
Currency impact of long-term funding	(1,046)				(1,046)
Tax on currency impact of long- term funding	(87)				(87)
Unrealized capital gain (loss) - investments	(239)				(239)
Actuarial gain on defined benefit pension plan	1,383				1,383
Total comprehensive income	113,548
Exercise of share options (in shares)		1,249,759
Exercise of share options	26,989	$ 101	26,888
Issue of restricted share units (in shares)		50,000
Issue of restricted share units	4		4
Share based compensation expense	13,882		13,882
Share issue costs	(70)		(70)
Excess tax benefit on exercise of equity compensation	1,651		1,651
Balance (in shares) at Dec. 31, 2013		61,587,257
Balance at Dec. 31, 2013	910,579	$ 5,168	279,572	100	1,960	623,779
Comprehensive Income:
Net income	172,468					172,468
Currency translation adjustment	(45,038)				(45,038)
Currency impact of long-term funding	9,806				9,806
Tax on currency impact of long- term funding	(178)				(178)
Unrealized capital gain (loss) - investments	20				20
Actuarial gain on defined benefit pension plan	(4,125)				(4,125)
Total comprehensive income	132,953
Exercise of share options (in shares)		926,407
Exercise of share options	22,256	$ 74	22,182
Issue of restricted share units (in shares)		233,726
Issue of restricted share units	18		18
Share based compensation expense	23,078		23,078
Share issue costs	(20)		(20)
Repurchase of ordinary shares (in shares)		(2,640,610)
Repurchase of ordinary shares	(140,030)	$ (205)		205		(140,030)
Share repurchase costs	(1,032)					(1,032)
Excess tax benefit on exercise of equity compensation	$ 2,404		2,404
Balance (in shares) at Dec. 31, 2014	60,106,780	60,106,780
Balance at Dec. 31, 2014	$ 950,206	$ 5,037	327,234	305	(37,555)	655,185
Comprehensive Income:
Net income	239,539					239,539
Currency translation adjustment	(35,105)				(35,105)
Currency impact of long-term funding	7,342				7,342
Tax on currency impact of long- term funding	(3,574)				(3,574)
Unrealized capital gain (loss) - investments	(54)				(54)
Actuarial gain on defined benefit pension plan	2,693				2,693
Gain on interest rate hedge	4,617				4,617
Total comprehensive income	215,458
Exercise of share options (in shares)		773,753
Exercise of share options	20,981	$ 52	20,929
Issue of restricted/performance share units (in shares)		276,860
Issue of restricted/performance share units	18		18
Share based compensation expense	33,317		33,317
Share issue costs	(8)		(8)
Repurchase of ordinary shares (in shares)		(6,198,481)
Repurchase of ordinary shares	(457,892)	$ (410)		410		(457,892)
Share repurchase costs	(889)					(889)
Excess tax benefit on exercise of equity compensation	$ 1,905		1,905
Balance (in shares) at Dec. 31, 2015	54,958,912	54,958,912
Balance at Dec. 31, 2015	$ 763,096	$ 4,679	$ 383,395	$ 715	$ (61,636)	$ 435,943

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities:
Net income	$ 239,539	$ 172,468	$ 102,812
Adjustments to reconcile net income to net cash provided by operating activities:
Loss on disposal of property, plant and equipment	55	248	662
Depreciation expense	40,210	42,200	38,975
Amortization of intangibles	17,467	10,342	7,539
Amortization of government grants	53	(213)	(349)
Amortization of gain on interest rate hedge	(41)
Stock compensation expense	33,317	22,742	14,220
Deferred taxes	3,157	(7,900)	(10,583)
Changes in assets and liabilities:
Increase in accounts receivable	(18,671)	(7,032)	(37,538)
Increase in unbilled revenue	(29,281)	(13,671)	(4,015)
Increase in other receivables	(14,519)	(4,259)	(1,638)
Increase in prepayments and other current assets	(8,631)	(3,574)	(898)
Increase in other non current assets	(55)	(2,264)	(1,146)
Increase/(decrease) in payments on account	34,644	(47,548)	76,066
(Decrease)/increase in other current liabilities	(26,266)	15,111	43,291
Increase in other non current liabilities	6,378	1,283	899
Increase/(decrease) in income taxes payable	(949)	3,021	(5,013)
Increase/(decrease) in accounts payable	3,124	(11,006)	(2,057)
Net cash provided by operating activities	279,531	169,948	221,227
Cash flows from investing activities:
Purchase of property, plant and equipment	(49,730)	(32,779)	(29,488)
Purchase of subsidiary undertakings and acquisition costs	(166,292)	(124,301)	(93,553)
Cash acquired with subsidiary undertaking	194	3,527	1,039
Sale of short term investments	25,250	102,565	109,795
Purchase of short term investments	(14,194)	(61,328)	(172,168)
Net cash used in investing activities	(204,772)	(112,316)	(184,375)
Cash flows from financing activities:
Drawdown of credit lines and facilities	851,500
Repayment of credit lines and facilities	(501,500)
Proceeds from the exercise of equity compensation	20,999	22,274	26,993
Share issuance costs	(8)	(20)	(70)
Excess tax benefit on exercise of equity compensation	1,905	2,404	1,651
Repurchase of ordinary shares	(457,892)	(140,030)
Share repurchase costs	(889)	(1,032)
Receipt of government grant			225
Repayment of government grant	(159)
Proceeds from interest rate hedge	4,658
Net cash (used in)/provided by financing activities	(81,386)	(116,404)	28,799
Effect of exchange rate movements on cash	(8,362)	(4,847)	2,821
Net (decrease)/increase in cash and cash equivalents	(14,989)	(63,619)	68,472
Cash and cash equivalents at beginning of year	118,900	182,519	114,047
Cash and cash equivalents at end of year	$ 103,911	$ 118,900	$ 182,519

Description of business

12 Months Ended

Dec. 31, 2015

Description of business

1. Description of business

ICON plc and its subsidiaries (“the Company” or “ICON”) is a contract research organization (“CRO”), providing outsourced development services on a global basis to the pharmaceutical, biotechnology and medical device industries. We specialize in the strategic development, management and analysis of programs that support all stages of the clinical development process from compound selection to Phase I-IV clinical studies. Our vision is to be the Global CRO partner of choice in drug development by delivering best in class information, solutions and performance in clinical and outcomes research.

We believe that we are one of a select group of CROs with the expertise and capability to conduct clinical trials in most major therapeutic areas on a global basis and have the operational flexibility to provide development services on a stand-alone basis or as part of an integrated “full service” solution. At December 31, 2015 we had approximately 11,900 employees, in 90 locations in 37 countries. During the year ended December 31, 2015, we derived approximately 41.3%, 48.3% and 10.4% of our net revenue in the United States, Europe and Rest of World, respectively.

We began operations in 1990 and have expanded our business predominately through internal growth, together with a number of strategic acquisitions to enhance our capabilities and expertise in certain areas of the clinical development process. We are incorporated in Ireland and our principal executive office is located at: South County Business Park, Leopardstown, Dublin 18, Republic of Ireland. The contact telephone number of this office is 011- 353-1- 291-2000.

Significant Accounting Policies

12 Months Ended

Dec. 31, 2015

Significant Accounting Policies

2. Significant Accounting Policies

The accounting policies noted below were applied in the preparation of the accompanying financial statements of the Company and are in conformity with accounting principles generally accepted in the United States.

(a) Basis of consolidation

The consolidated financial statements include the financial statements of the Company and all of its subsidiaries. All significant intercompany profits, transactions and account balances have been eliminated. The results of subsidiary undertakings acquired in the period are included in the consolidated statement of operations from the date of acquisition.

(b) Use of estimates

The preparation of financial statements in conformity with generally accepted accounting principles in the United States requires management to make estimates and judgments that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reported period. Actual results could differ from those estimates. The principle management estimates and judgments used in preparing the financial statements relate to revenue recognition, taxation, goodwill and business combinations.

The Company primarily earns revenues by providing a number of different services to its customers. These services, which are integral elements of the clinical development process, include clinical trials management, biometric activities, consulting, imaging, contract staffing, informatics and laboratory services. Contracts range in duration from a number of months to several years. Revenue for services, as rendered, is recognized only after persuasive evidence of an arrangement exists, the sales price is fixed or determinable and collectability is reasonably assured.

Clinical trials management revenue is recognized on a proportional performance method. Depending on the contractual terms revenue is either recognized on the percentage of completion method based on the relationship between hours incurred and the total estimated hours of the trial or on the unit of delivery method. Contract costs equate to the product of labor hours incurred and compensation rates. For the percentage of completion method, the input (effort expended) method has been used to measure progress towards completion as there is a direct relationship between input and productivity. Contract revenue is the product of the aggregated labor hours required to complete the specified contract tasks at the agreed contract rates. The Company regularly reviews the estimate of total contract time to ensure such estimates remain appropriate taking into account actual contract stage of completion, remaining time to complete and any identified changes to the contract scope. Remaining time to complete depends on the specific contract tasks and the complexity of the contract and can include geographical site selection and initiation, patient enrolment, patient testing and level of results analysis required. While the Company may routinely adjust time estimates, the Company’s estimates and assumptions historically have been accurate in all material respects in the aggregate. Where revenue is recognized on the unit of delivery method, the basis applied is the number of units completed as a percentage of the total number of contractual units.

Biometrics revenue is recognized on a fee-for-service method as each unit of data is prepared on the basis of the number of units completed in a period as a percentage of the total number of contracted units. Imaging revenue is recognized on a fee-for-service basis recognizing revenue for each image completed. Consulting revenue is recognized on a fee-for-service basis as each hour of the related service is performed. Contract staffing revenue is recognized on a fee-for-service basis, over the time the related service is performed, or in the case of permanent placement, once the candidate has been placed with the client. Informatics revenue is recognized on a fee-for-service basis. Informatics contracts are treated as multiple element arrangements, with contractual elements comprising licence fee revenue, support fee revenue and revenue from software services, each of which can be sold separately. Sales prices for contractual elements are determined by reference to objective and reliable evidence of their sales price. Licence and support fee revenues are recognized rateably over the period of the related agreement. Revenue from software services is recognized using the percentage of completion method based on the relationship between hours incurred and the total estimated hours required to perform the service.

Laboratory service revenue is recognized on a fee-for-service basis. The Company accounts for laboratory service contracts as multiple element arrangements, with contractual elements comprising laboratory kits and laboratory testing, each of which can be sold separately. Sales prices for contractual elements are determined by reference to objective and reliable evidence of their sales price. Revenues for contractual elements are recognized on the basis of the number of deliverable units completed in the period.

Contracts generally contain provisions for renegotiation in the event of changes in the scope, nature, duration, or volume of services of the contract. Renegotiated amounts are recognized as revenue by revision to the total contract value arising as a result of an authorised customer change order.

The difference between the amount of revenue recognized and the amount billed on a particular contract is included in the balance sheet as unbilled revenue or payments on account. Normally, amounts become billable upon the achievement of certain milestones, for example, target patient enrolment rates, clinical testing sites initiated or case report forms completed. Once the milestone target is reached, amounts become billable in accordance with pre-agreed payment schedules included in the contract or on submission of appropriate billing detail. Such cash payments are not representative of revenue earned on the contract as revenues are recognized over the period in which the specified contractual obligations are fulfilled. Amounts included in unbilled revenue are expected to be collected within one year and are included within current assets. Advance billings to customers, for which revenue has not been recognized, are recognized as payments on account within current liabilities.

In the event of contract termination, if the value of work performed and recognized as revenue is greater than aggregate milestone billings at the date of termination, cancellation clauses usually ensure that the Company is paid for all work performed to the termination date.

(d) Reimbursable expenses

Reimbursable expenses comprise investigator payments and certain other costs which are reimbursed by clients under terms specific to each contract and are deducted from gross revenue in arriving at net revenue. Investigator payments are accrued based on patient enrollment over the life of the contract. Investigator payments are made based on predetermined contractual arrangements, which may differ from the accrual of the expense.

(e) Direct costs

Direct costs consist of compensation, associated employee benefits and share-based payments for project-related employees and other direct project-related costs.

(f) Advertising costs

All costs associated with advertising and promotion are expensed as incurred. The advertising and promotion expense was $4,513,750, $3,563,900 and $5,195,120 for the years ended December 31, 2015, December 31, 2014 and December 31, 2013 respectively.

(g) Foreign currencies and translation of subsidiaries

The Company's financial statements are prepared in United States dollars. Transactions in currencies other than United States dollars are recorded at the rate ruling at the date of the transactions. Monetary assets and liabilities denominated in currencies other than United States dollars are translated into United States dollars at exchange rates prevailing at the balance sheet date. Adjustments resulting from these translations are charged or credited to income. Amounts credited or charged to the statement of operations for the years ended December 31, 2015, December 31, 2014 and December 31, 2013 were as follows:

	Year ended December 31,
	(in thousands)
	2015			2014			2013
Amounts (credited)	$	(3,608	)	$	(5,942	)	$	(1,233	)

The financial statements of subsidiaries with other functional currencies are translated at period end rates for the balance sheet and average rates for the statement of operations. Translation gains and losses arising are reported as a movement on accumulated other comprehensive income.

(h) Disclosure about fair value of financial instruments

The following methods and assumptions were used to estimate the fair value of each material class of financial instrument:

Cash, cash equivalents, unbilled revenue, other receivables, short term investments, prepayments and other current assets, accounts receivable, accounts payable, investigator payments, payments on account, accrued liabilities, accrued bonuses and income taxes payable have carrying amounts that approximate fair value due to the short term maturities of these instruments. Other liabilities’ carrying amounts approximate fair value based on net present value of estimated future cash flows.

(i) Business combinations

The cost of a business combination is measured as the aggregate of the fair values at the date of exchange of assets given, liabilities incurred or assumed and equity instruments issued in exchange for control. Where a business combination agreement provides for an adjustment to the cost of the acquisition which is contingent upon future events, the amount of the estimated adjustment is recognized at the acquisition date at the fair value of this contingent consideration. Any changes to this estimate in subsequent periods will depend on the classification of the contingent consideration. If the contingent consideration is classified as equity it shall not be re-measured and the settlement shall be accounted for within equity. If the contingent consideration is classified as a liability any adjustments will be accounted for through the Consolidated Statement of Operations or Other Comprehensive Income depending on whether the liability is considered a financial instrument.

The assets, liabilities and contingent liabilities of businesses acquired are measured at their fair values at the date of acquisition. In the case of a business combination which is completed in stages, the fair values of the identifiable assets, liabilities and contingent liabilities are determined at the date of each exchange transaction. When the initial accounting for a business combination is determined provisionally, any subsequent adjustments to the provisional values allocated to the identifiable assets, liabilities and contingent liabilities are made within twelve months of the acquisition date and presented as adjustments to the original acquisition accounting.

(j) Goodwill and Impairment

Goodwill represents the excess of the cost of acquired entities over the net amounts assigned to assets acquired and liabilities assumed. Goodwill primarily comprises acquired workforce in place which does not qualify for recognition as an asset apart from goodwill. Goodwill is stated net of any provision for impairment. The Company tests goodwill annually for any impairments or whenever events occur which may indicate impairment. The first step is to compare the carrying amount of the reporting unit’s assets to the fair value of the reporting unit. If the carrying amount exceeds the fair value then a second step is completed which involves the fair value of the reporting unit being allocated to each asset and liability with the excess being implied goodwill. The impairment loss is the amount by which the recorded goodwill exceeds the implied goodwill. No impairment was recognized as a result of the impairment testing carried out for the years ended December 31, 2015, December 31, 2014 and December 31, 2013.

(k) Intangible assets

Intangible assets are amortized on a straight line basis over their estimated useful life.

(l) Cash and cash equivalents

Cash and cash equivalents include cash and highly liquid investments with initial maturities of three months or less and are stated at cost, which approximates market value.

(m) Short term investments - available for sale

The Company classifies short-term investments as available for sale in accordance with the terms of FASB ASC 320, Investments – Debt and Equity Securities. Realized gains and losses are determined using specific identification. The investments are reported at fair value, with unrealized gains or losses reported in a separate component of shareholders’ equity. Any differences between the cost and fair value of the investments are represented by accrued interest.

(n) Inventory

Inventory is valued at the lower of cost and market value and after provisions for obsolescence. Cost of inventories comprises the purchase price and attributable costs, less trade discounts. At December 31, 2015 the carrying value of inventory, included within prepayments and other current assets on the balance sheet, was $1.8 million (2014: $1.7 million).

(o) Property, plant and equipment

Property, plant and equipment is stated at cost less accumulated depreciation. Depreciation of property, plant and equipment is computed using the straight line method based on the estimated useful lives of the assets as listed below:

	Years
Building		40
Computer equipment and software		2-8
Office furniture and fixtures		8
Laboratory equipment		5
Motor vehicles		5

Leasehold improvements are amortized using the straight-line method over the estimated useful life of the asset or the lease term, whichever is shorter.

(p) Leased assets

Costs in respect of operating leases are charged to the statement of operations on a straight line basis over the lease term.

Assets acquired under capital finance leases are included in the balance sheet at the present value of the future minimum lease payments and are depreciated over the shorter of the lease term and their remaining useful lives. The corresponding liabilities are recorded in the balance sheet and the interest element of the capital lease rental is charged to interest expense.

(q) Income taxes

The Company applies the asset and liability method of accounting for income taxes. Under the asset and liability method, deferred tax assets and liabilities are recognized for the future tax consequences attributable to differences between the financial statement carrying amounts of existing assets and liabilities and their respective tax bases, and operating loss and tax credit carryforwards. Deferred tax assets and liabilities are measured using enacted tax rates expected to apply to taxable income in the years in which these temporary differences are expected to be recovered or settled. The effect on deferred tax assets and liabilities of a change in tax rates is recognized in income in the period that includes the enactment date. The Company recognizes the effect of income tax positions only if those positions are more likely than not of being sustained. Recognized income tax positions are measured at the largest amount of tax benefit that is greater than 50 percent likely of being realized upon settlement. Interest and penalties related to income taxes are included in income tax expense and classified with the related liability on the consolidated balance sheet.

On November 21, 2015 FASB issued ASU 2015-17 on the balance sheet classification of deferred taxes. The new standard requires that all deferred taxes are presented as noncurrent in a classified statement of financial position. The new guidance is effective for public business entities for annual periods beginning after December 15, 2016 and for nonpublic business entities for annual periods beginning after December 15, 2017. Early adoption is available for all entities for any set of financial statements that had not been released as at November 21, 2015 with an option to apply on either a prospective or a retrospective basis. The Company has elected for early adoption of ASU 2015 – 17 on a prospective basis for all financial statements issued after November 21, 2015. The effect of this is that all deferred tax assets and liabilities are classified as noncurrent assets and liabilities in the December 31, 2015 balance sheet. As ASU 2015-17 is being adopted on a prospective basis there is no impact on prior period financial statements.

(r) Government grants

Government grants received relating to capital expenditures are shown as deferred income and credited to income on a basis consistent with the depreciation policy of the relevant assets. Grants relating to categories of operating expenditures are credited to income in the period in which the expenditure to which they relate is charged.

Under the grant agreements amounts received may become repayable in full should certain circumstances specified within the grant agreements occur, including downsizing by the Company, disposing of the related assets, ceasing to carry on its business or the appointment of a receiver over any of its assets. The Company has not recognized any loss contingency having assessed as remote the likelihood of these events arising.

(s) Research and development credits

Research and development credits are available to the Company under the tax laws in certain jurisdictions, based on qualifying research and development spend as defined under those tax laws. Research and development credits are generally recognized as a reduction of income tax expense. However, certain tax jurisdictions provide refundable credits that are not wholly dependent on the Company’s ongoing income tax status or income tax position. In these circumstances the benefit of these credits is not recorded as a reduction to income tax expense, but rather as a reduction of operating expenditure.

(t) Pension costs

The Company contributes to defined contribution plans covering all eligible employees. The Company contributes to these plans based upon various fixed percentages of employee compensation and such contributions are expensed as incurred.

The Company operates, through a subsidiary, a defined benefit plan for certain of its United Kingdom employees. The Company accounts for the costs of this plan using actuarial models required by FASB ASC 715-30 and the plan is presented in accordance with the requirements of FASB ASC 715-60 Defined Benefit Plans – Other Post retirement.

(u) Net income per ordinary share

Basic net income per ordinary share has been computed by dividing net income available to ordinary shareholders by the weighted average number of ordinary shares outstanding during the period. Diluted net income per ordinary share is computed by adjusting the weighted average number of ordinary shares outstanding during the period for all potentially dilutive ordinary shares outstanding during the period and adjusting net income for any changes in income or loss that would result from the conversion of such potential ordinary shares.

There is no difference in net income used for basic and diluted net income per ordinary share. The reconciliation of the number of shares used in the computation of basic and diluted net income per ordinary share is as follows:

	Year Ended December 31,
	2015		2014		2013
Weighted average number of ordinary shares outstanding for basic net income per ordinary share		58,746,935		61,496,115		60,907,274
Effect of dilutive share options outstanding		1,543,098		1,635,302		1,345,977
Weighted average number of ordinary shares outstanding for diluted net income per ordinary share		60,290,033		63,131,417		62,253,251

(v) Share-based compensation

The Company accounts for its share options, restricted share units (“RSU’s”) and performance share units (“PSU’s”) in accordance with the provisions of FASB ASC 718, Compensation – Stock Compensation. Share-based compensation expense for equity-settled awards made to employees and Directors is measured and recognized based on estimated grant date fair values. These equity-settled awards include employee share options, RSU’s and PSU’s.

Share-based compensation expense for share options awarded to employees and Directors is estimated at the grant date based on each option’s fair value as calculated using the Black-Scholes option-pricing model. Share-based compensation for RSU’s and PSU’s awarded to employees and Directors is calculated based on the market value of the Company’s shares on the date of award of the RSU’s and PSU’s. The value of awards expected to vest is recognized as an expense over the requisite service periods. Forfeitures are estimated on the date of grant and revised if actual or expected forfeiture activity differs materially from original estimates.

Estimating the grant date fair value of share options as of the grant date using an option-pricing model, such as the Black-Scholes model, is affected by the Company’s share price as well as assumptions regarding a number of complex variables. These variables include, but are not limited to, the expected share price volatility over the term of the awards, risk-free interest rates, and the expected term of the awards.

(w) Impairment of long-lived assets

Long-lived assets are reviewed for impairment whenever events or changes in circumstances indicate that the carrying amount of an asset may not be recoverable. Recoverability of assets to be held and used is measured by a comparison of the carrying amount of an asset to future undiscounted net cash flows expected to be generated by the asset. If such assets are considered to be impaired, the impairment to be recognized is measured by the amount by which the carrying amount of the assets exceeds the fair value of the assets. Assets to be disposed of are reported at the lower of the carrying amount of the asset or fair value less selling costs.

(x) Derivative financial instruments

We enter into transactions in the normal course of business using various financial instruments in order to hedge against exposures to fluctuating exchange and interest rates. We use derivative financial instruments to reduce exposure to fluctuations in interest rates. A derivative is a financial instrument or other contract whose value changes in response to some underlying variable, which has an initial net investment smaller than would be required for other instruments that have a similar response to the variable and that will be settled at a future date. We do not enter into derivative financial instruments for trading or speculative purposes. We did not hold any interest rate swap contracts or forward currency contracts at December 31, 2015, December 31, 2014 or December 31, 2013.

Our accounting policies for derivative financial instruments are based on whether they meet the criteria for designation as cash flow or fair value hedges. A designated hedge of the exposure to variability in the future cash flows of an asset or a liability, or of a forecasted transaction, is referred to as a cash flow hedge. A designated hedge of the exposure to changes in fair value of an asset or a liability is referred to as a fair value hedge. The criteria for designating a derivative as a hedge include the assessment of the instrument’s effectiveness in risk reduction, matching of the derivative instrument to its underlying transaction, and the probability that the underlying transaction will occur. For derivatives with cash flow hedge accounting designation, we report the gain or loss from the effective portion of the hedge as a component of Other Comprehensive Income and reclassify it into earnings in the same period or periods in which the hedged transaction affects earnings, and within the same income statement line item as the impact of the hedged transaction. For derivatives with fair value hedge accounting designation, we recognize gains or losses from the change in fair value of these derivatives, as well as the offsetting change in the fair value of the underlying hedged item, in earnings. Fair value gains and losses arising on derivative financial instruments not qualifying for hedge accounting are reported in our Consolidated Statement of Operations.

(y) Financing costs and gain on interest rate hedge

The interest rate in respect of the Senior Notes is fixed at 3.64% for the five year term of the agreement. The associated interest cost is recognized in interest expense in the period since drawdown in December 2015.

On October 5 2015, the Company entered into an interest rate hedge in respect of the planned issuance of the Senior Notes in December 2015. The interest rate hedge matured on November 17, 2015 when the interest rate on the Senior Notes was fixed. The interest rate hedge was effective in accordance with Financial Accounting Standards Board (“FASB”) ASC 815, “Derivatives and Hedging”. The cash proceeds ($4.6 million), representing the realized gain on the interest rate hedge were received on maturity in November 2015 and are recorded within Other Comprehensive Income. The realized gain will be amortized to the income statement, net against interest payable, over the period of the Senior Notes.

Deferred financing costs (including issue costs relating to the Senior Notes) are reported at cost less accumulated amortization and the related amortization expense is included in interest expense, in our consolidated statement of income.

(y) Reclassifications

Certain amounts in the consolidated financial statements have been reclassified where necessary to conform to the current year presentation.

Goodwill

12 Months Ended

Dec. 31, 2015

Goodwill

4. Goodwill

	December 31,			December 31,
	2015			2014
	(in thousands)
Opening goodwill	$	463,324		$	357,523
Current year acquisitions (note 4 (a) and (b))		133,123			121,209
Prior period acquisition (note 4(c))		4,418			-
Foreign exchange movement		(12,431	)		(15,408	)
Closing goodwill	$	588,434		$	463,324

The Company has made a number of strategic acquisitions since inception to enhance its capabilities and experience in certain areas of the clinical development process. Goodwill arising on acquisition represents the excess of the cost of acquired entities over the net amounts assigned to assets acquired and liabilities assumed. Goodwill primarily comprises of the acquired workforce in place which does not qualify for recognition as an asset apart from goodwill.

The Company acquired PMG and MediMedia Pharma Solutions during the year-ended December 31, 2015 resulting in recognition of goodwill of $41.0 million and $92.1 million (note 4(a) and note 4 (b)) respectively.

The Company tests goodwill annually for impairment or whenever events occur which may indicate impairment. The results of the Company’s goodwill impairment testing during the year ended December 31, 2015 provided no evidence of impairment and indicated the existence of sufficient headroom such that a reasonably possible change to the key assumptions used would be unlikely to result in an impairment of the related goodwill.

(a) Acquisitions of PMG

On December 4, 2015 the Company acquired PMG for cash consideration of $53.7 million. The Company also made certain payments on behalf of PMG totalling $9.9 million. PMG is an integrated network of 48 clinical research sites in North Carolina, South Carolina, Tennessee and Illinois. The site network includes wholly owned facilities and dedicated clinical research sites. PMG conducts clinical trials in all major therapeutic areas and has particular expertise in vaccine, gastroenterology, cardiovascular, neurology and endocrinology studies. It has a proprietary database of clinical trial participants. It also has access to in excess of 2 million active patients via electronic medical records through its partnerships with healthcare institutions and community physical practices. The acquisition agreement provides for working capital targets to be achieved by PMG within 90 days of acquisition.

The acquisition of PMG has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations. The Company has made a provisional assessment of the fair value of assets acquired and liabilities assumed as at that date. The table following summarizes the Company’s provisional estimates of the fair values of the assets acquired and liabilities assumed:

	December 4,
	2015
	(in thousands)
Cash	$	194
Property, plant and equipment		712
Goodwill*		41,039
Intangible asset**		10,259
Accounts receivable		12,997
Prepayments and other current assets		1,329
Accounts payable		(530	)
Other liabilities		(2,459	)
Net assets acquired		63,541

Cash consideration			53,681
Other liabilities assumed			9,860
Total cash outflows			63,541

*Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development.

**The Company has estimated a separate intangible asset (in respect of customer lists acquired) of $10.3 million. This assessment is under review and will be finalized within 12 months of the date of acquisition.

The proforma effect of the PMG acquisition if completed on January 1, 2015 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2015 and December 31, 2014 as follows:

	Year Ended
	December 31,
	2015		2014
	(in thousands)
Net revenue	$	1,601,891	$	1,527,685
Net income	$	243,004	$	172,390
Basic earnings per share	$	4.14	$	2.80
Diluted earnings per share	$	4.03	$	2.73

(b) Acquisitions of MediMedia Pharma Solutions

On February 27, 2015 the Company acquired MediMedia Pharma Solutions for cash consideration of $104.8 million (net of working capital adjustments of $3.9 million). In addition to the cash consideration, certain payments were made on behalf of MediMedia Pharma Solutions on completion totalling $11.3 million. Headquartered in Yardley, Pennsylvania, MediMedia Pharma Solutions includes MediMedia Managed Markets and Complete Healthcare Communications. MediMedia Managed Markets is a leading provider of strategic payer-validated market access solutions. Complete Healthcare Communications is one of the leading medical and scientific communication agencies working with medical affairs, commercial and brand development teams within life science companies. The acquisition agreement also provides for certain working capital targets to be achieved by MediMedia Pharma Solutions.

The acquisition of MediMedia Pharma Solutions has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations. The following table summarizes the Company’s provisional estimates of the fair values of the assets acquired and liabilities assumed:

	February 27,
	2015
	(in thousands)
Property, plant and equipment	$	1,049
Goodwill*		92,084
Customer lists		22,752
Order backlog		2,521
Accounts receivable		5,240
Unbilled Revenue		4,324
Prepayments and other current assets		621
Accounts payable		(749	)
Payments on account		(4,186	)
Deferred tax liability		(2,171	)
Other liabilities		(5,483	)
Net assets acquired	$	116,002


Cash consideration	$	108,717
Other liabilities assumed**		11,283
Gross cash outflows		120,000
Working capital adjustment		(3,998	)
Net cash outflows	$	116,002

Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry.

**	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.

The proforma effect of the MediMedia Pharma Solutions acquisition if completed on January 1, 2015 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2015 and December 31, 2014 as follows:

	Year Ended
	December 31,
	2015		2014
	(in thousands)
Net revenue	$	1,581,816	$	1,556,936
Net income	$	239,361	$	179,289
Basic earnings per share	$	4.07	$	2.92
Diluted earnings per share	$	3.97	$	2.84

On May 7, 2014 the Company acquired 100% of the common stock of Aptiv Solutions (“Aptiv”), a global biopharmaceutical and medical device development services company and leader in adaptive clinical trials for cash consideration of $143.5 million, including certain payments to be made on behalf of the company on completion totaling $22.4 million. The acquisition agreement provided for working capital targets to be achieved. On March 25, 2015, the Company received $1.9 million in respect of these targets on completion of the working capital review. Aptiv offers full-service clinical trial consulting and regulatory support for drugs, medical devices and diagnostics with a specific focus on strategies to increase product development efficiency and productivity. It is a market leader in the integrated design and execution of adaptive clinical trials for exploratory and late phase development as well as being an industry leader in medical device and diagnostic development in key medical technology segments.

The acquisition of Aptiv has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations. The following table summarizes the fair values of the assets acquired and the liabilities assumed:

	May 7,
	2014
	(in thousands)
Property, plant and equipment	$	6,924
Goodwill*		125,627
Customer relationships		21,400
Order backlog		7,900
Cash and cash equivalents		3,484
Accounts receivable		25,091
Unbilled revenue		21,154
Prepayments and other current assets		4,180
Non-current assets		2,911
Accounts payable		(9,565	)
Other liabilities		(29,782	)
Payments on account		(31,094	)
Non-current other liabilities		(11,303	)
Loan notes payable**		(17,790	)
Net assets acquired	$	119,137


Cash consideration			$143,500
Working capital adjustment			(1,964)
			141,536
Adjustments to cash consideration**			(22,399)
Net purchase consideration			$119,137

**Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.

The proforma effect of the Aptiv Solutions acquisition if completed on January 1, 2013 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2013 and December 31, 2014 as follows:

	Year Ended
	December 31,
	2014		2013
	(in thousands)
Net revenue	$	1,543,820	$	1,451,682
Net income	$	172,508	$	101,857
Basic earnings per share	$	2.81	$	1.67
Diluted earnings per share	$	2.73	$	1.64

(d) Acquisition of Clinical Trial Services Division of Cross Country Healthcare, Inc.

On February 15, 2013 the Company acquired the clinical trial services division of Cross Country Healthcare Inc. for an initial cash consideration of $51.9 million. Cross Country Healthcare’s Clinical Trial Services division includes US resourcing providers, ClinForce and Assent Consulting, whose services include contract staffing, permanent placement and functional service provision. The division also includes AKOS, a leading US and EU provider of pharmacovigilance and drug safety services. ClinForce and Assent have been combined with ICON’s functional service provision (“FSP”) division, DOCS, creating a leader in global resourcing and FSP, while AKOS has enhanced the services offered by ICON’s medical and safety services team.

The acquisition agreement also provided for certain working capital targets to be achieved by the clinical trial services division of Cross Country Healthcare, Inc on completion. In October 2013 the Company received $0.2 million on completion of this review.

The acquisition of the clinical trial services division of Cross Country Healthcare, Inc has been accounted for as a business combination in accordance with FASB ASC 805 Business Combinations. The following table summarizes the estimated fair values of the assets acquired and the liabilities assumed:

	February 15,
	2013
	(in thousands)
Property, plant and equipment	$	339
Goodwill*		36,922
Intangible asset – customer relationships		3,300
Intangible asset – order backlog		600
Cash and cash equivalents		1,039
Accounts receivable		9,200
Unbilled revenue		2,128
Prepayments and other current assets		465
Non-current assets		6
Other liabilities		(2,285	)
Non-current other liabilities		(16	)
Net assets acquired	$	51,698


Cash consideration	$	51,897
Working capital adjustment		(199	)
Net purchase consideration	$	51,698

* Goodwill represents the acquisition of an established workforce with experience in the clinical research industry, thereby allowing the Company to enhance its capabilities in global resourcing and FSP and also medical and safety services. Goodwill related to the US portion of the business acquired is tax deductible.

The proforma effect of the clinical trial services division of Cross Country Healthcare, Inc acquisition if completed on January 1, 2012 would have resulted in net revenue, net income and earnings per share for the fiscal years ended December 31, 2012 and December 31, 2013 as follows:

	Year Ended
	December 31,
	2013		2012
	(in thousands)
Net revenue	$	1,343,996	$	1,182,734
Net income	$	103,133	$	58,944
Basic earnings per share	$	1.69	$	0.98
Diluted earnings per share	$	1.66	$	0.98

Intangible Assets

12 Months Ended

Dec. 31, 2015

Intangible Assets

5. Intangible Assets

	December 31,			December 31,
	2015			2014
Cost	(in thousands)
Customer relationships acquired	$	90,541		$	36,130
Technology asset acquired		11,169			11,169
Order backlog		13,592			3,171
Tradenames acquired		1,357			1,357
Volunteer list acquired		1,325			1,325
Non-compete arrangements		489			489
Aptiv intangible asset		-			30,037
Foreign exchange movement		(5,092	)		(2,769	)
Total cost		113,381			80,909
Accumulated amortization		(49,587	)		(32,120	)
Foreign exchange movement		2,333			930
Net book value	$	66,127		$	49,719

On December 4, 2015 the Company acquired PMG, an integrated network of 48 clinical research sites in North Carolina, South Carolina, Tennessee and Illinois. The site network includes wholly owned facilities and dedicated clinical research sites. PMG conducts clinical trials in all major therapeutic areas and has particular expertise in vaccine, gastroenterology, cardiovascular, neurology and endocrinology studies. The value of certain customer relationships identified of $10.3 million is being amortized over approximately 6 years, the estimated period of benefit. $170,000 has been amortized in the period since the date of acquisition.

On February 27, 2015 the Company acquired MediMedia Pharma Solutions. Headquartered in Yardley, Pennsylvania, MediMedia Pharma Solutions includes MediMedia Managed Markets and Complete Healthcare Communications. MediMedia Managed Markets is a leading provider of strategic payer-validated market access solutions. Complete Healthcare Communications is one of the leading medical and scientific communication agencies working with medical affairs, commercial and brand development teams within life science companies. The value of certain customer relationships and order backlog identified of $22.8 million and $2.5 million respectively are being amortized over approximately 7 years and 1 year, the estimated period of benefit. $4.8 million has been amortized in the period since the date of acquisition.

On May 7, 2014 the Company acquired Aptiv Solutions (“Aptiv”), a global biopharmaceutical and medical device development services company and leader in adaptive clinical trials. Aptiv offers full-service clinical trial consulting and regulatory support for drugs, medical devices and diagnostics with a specific focus on strategy to increase product development efficiency and productivity. The value of certain customer relationships and order backlog identified of $21.4 million and $7.9 million respectively are being amortized over approximately 7 years and 3 years, the estimated period of benefit. $9,484,000 has been amortized in the period since the date of acquisition.

On February 15, 2013 the Company acquired the Clinical Trial Services division of Cross Country Healthcare, Inc. Cross Country Healthcare’s Clinical Trial Services division includes US resourcing providers, ClinForce and Assent Consulting, whose services include contract staffing, permanent placement and functional service provision (“FSP”). The value of certain customer relationships and order backlog identified of $3.3 million and $0.6 million respectively are being amortized over approximately 3 years and 1 year, the estimated period of benefit. $3,763,000 has been amortized in the period since the date of acquisition.

On February 28, 2012 the Company acquired PriceSpective, a strategy consulting company. The value of certain customer relationships identified of $10.2 million is being amortized over approximately 10 years, the estimated period of benefit. The value of order backlog and certain non-compete arrangements identified of $0.4 million and $0.4 million respectively are being amortized over approximately 0.8 and 3 years, the estimated period of benefit. $4,720,000 has been amortized in the period since the date of acquisition.

On February 15, 2012 the Company acquired BeijingWits Medical, a Chinese CRO. The value of certain customer relationships and order backlog identified of $1.8 million and $0.4 million respectively are being amortized over approximately 10 and 4 years, the estimated period of benefit. The value of certain non-compete arrangements identified of $0.01 million are being amortized over approximately 5 years, the estimated period of benefit. $1,136,000 has been amortized in the period since the date of acquisition.

On July 14, 2011 the Company acquired Firecrest Clinical Limited, a provider of technology solutions that boost investigator site performance and study management. The value of certain technology assets and customer relationships identified of $11.2 million and $5.2 million respectively are being amortized over approximately 7.5 years, the estimated period of benefit. The value of the Firecrest tradename and order backlog identified of $1.4 million and $1.2 million respectively are being amortized over approximately 4.5 and 1.2 years, the estimated period of benefit. $11,103,000 has been amortized in the period since the date of acquisition.

On January 14, 2011 the Company acquired Oxford Outcomes Limited, an international health outcomes consultancy business. The value of certain customer relationships and order backlog identified of $6.6 million and $0.6 million respectively are being amortized over approximately 6.5 and 2 years, the estimated period of benefit. $5,795,000 has been amortized in the period since the date of acquisition.

On November 14, 2008 the Company acquired Prevalere Life Sciences, a US provider of bioanalytical and immunoassay laboratory services. The value of certain customer relationships identified of $7.4 million is being amortized over periods ranging from approximately 7 to 11 years, the estimated period of the benefit. $5,792,000 has been amortized in the period since the date of acquisition.

On February 11, 2008 the Company acquired Healthcare Discoveries, a US provider of Phase I clinical trial services. The value of certain client relationships identified of $1.6 million is being amortized over periods ranging from approximately 2 to 9 years, the estimated periods of benefit. The value of certain volunteer lists identified of $1.3 million is being amortized over approximately 6 years, the estimated period of benefit. $2,812,000 has been amortized in the period since the date of acquisition.

Future intangible asset amortization expense for the years ended December 31, 2016 to December 31, 2020 is as follows:

	Year ended December 31, (in thousands)
2016	$	15,599
2017		12,451
2018		11,034
2019		9,494
2020		9,215
	$	57,793

Property, Plant and Equipment, net

12 Months Ended

Dec. 31, 2015

Property, Plant and Equipment, net

6. Property, Plant and Equipment, net

	December 31,			December 31,
	2015			2014
	(in thousands)
Cost
Land	$	3,464		$	3,464
Building		80,861			88,580
Computer equipment and software		282,909			247,980
Office furniture and fixtures		65,152			64,690
Laboratory equipment		31,098			23,599
Leasehold improvements		20,647			19,516
Motor vehicles		47			47
		484,178			447,876
Less accumulated depreciation and asset write offs		(333,960	)		(299,691	)

Property, plant and equipment (net)	$	150,218		$	148,185

Employee Benefits

12 Months Ended

Dec. 31, 2015

Employee Benefits

9. Employee Benefits

Certain Company employees are eligible to participate in a defined contribution plan (the "Plan"). Participants in the Plan may elect to defer a portion of their pre-tax earnings into a pension plan, which is run by an independent party. The Company matches participant's contributions typically at 6% of the participant's annual compensation. Contributions to the plan are recorded, as an expense in the Consolidated Statement of Operations. Contributions for the years ended December 31, 2013, December 31, 2014 and December 31, 2015 were $20,293,000, $22,582,000 and $21,874,000 respectively.

The Company's United States operations maintain a retirement plan (the "U.S. Plan") that qualifies as a deferred salary arrangement under Section 401(k) of the Internal Revenue Code. Participants in the U.S. Plan may elect to defer a portion of their pre-tax earnings, up to the Internal Revenue Service annual contribution limit. The Company matches 50% of each participant's contributions; each participant can contribute up to 6% of their annual compensation. Contributions to this U.S. Plan are recorded, in the year contributed, as an expense in the Consolidated Statement of Operations. Contributions for the years ended December 31, 2013, December 31, 2014 and December 31, 2015 were $9,816,000, $10,514,000 and $12,802,000 respectively.

One of the Company’s subsidiaries, ICON Development Solutions Limited, operates a defined benefit pension plan in the United Kingdom for its employees. The plan is managed externally and the related pension costs and liabilities are assessed in accordance with the advice of a professionally qualified actuary. Plan assets at December 31, 2015, December 31, 2014 and December 31, 2013, consist of units held in independently administered funds. The pension costs of this plan are presented in the following tables in accordance with the requirements of ASC 715-60, Defined Benefit Plans – Other Postretirement. The plan has been closed to new entrants with effect from July 1, 2003.

Change in benefit obligation	December 31, 2015			December 31, 2014
	(in thousands)
Benefit obligation at beginning of year	$	32,875		$	24,958
Service cost		78			91
Interest cost		1,140			1,235
Plan participants’ contributions		26			44
Plan curtailments		-			359
Benefits paid		(1,111	)		(68	)
Actuarial (gain)/loss		(3,992	)		8,270
Foreign currency exchange rate changes		(1,647	)		(2,014	)
Benefit obligation at end of year	$	27,369		$	32,875

Change in plan assets	December 31, 2015			December 31, 2014
	(in thousands)
Fair value of plan assets at beginning of year	$	25,409		$	21,422
Actual return on plan assets		277			5,424
Employer contributions		114			155
Plan participants’ contributions		26			44
Benefits paid		(1,111	)		(68	)
Foreign currency exchange rate changes		(1,348	)		(1,568	)
Fair value of plan assets at end of year	$	23,367		$	25,409

The fair values of the assets above do not include any of the Company’s own financial instruments, property occupied by, or other assets used by, the Company.

Funded status	December 31, 2015			December 31, 2014
	(in thousands)
Projected benefit obligation	$	(27,369	)	$	(32,875	)
Fair value of plan assets		23,367			25,409
Funded status	$	(4,002	)	$	(7,466	)

Non-current other liabilities (note 8)	$	(4,002	)	$	(7,466	)

The following amounts were recorded in the consolidated statement of operations as components of the net periodic benefit cost:

	December 31, 2015			December 31, 2014			December 31, 2013
	(in thousands)
Service cost	$	78		$	91		$	251
Interest cost		1,140			1,235			1,005
Expected return on plan assets		(661	)		(1,299	)		(983	)
Amortization of net loss		224			20			130
Curtailment loss		-			359			-
Net periodic benefit cost	$	781		$	406		$	403

The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the years ended December 31, 2013, December 31, 2014 and December 31, 2015:


	December 31,			December 31,			December 31,
	2015			2014			2013
Discount rate		3.6	%		4.7	%		4.6	%
Rate of compensation increase		3.6	%		4.0	%		3.4	%
Expected rate of return on plan assets		2.7	%		6.1	%		5.7	%

Accumulated other comprehensive income	December 31, 2015				December 31, 2014		December 31, 2013
	(in thousands)
Actuarial (gain)/loss - benefit obligation	$	(3,992	)	$	8,270			$	680
Actuarial loss/(gain) – plan assets		384			(4,125	)			(1,933	)
Actuarial gain recognized in net periodic benefit cost		(224	)		(20	)			(130	)
Total	$	(3,832	)	$	4,125			$	(1,383	)

The estimated net gain and prior service cost for the defined benefit pension plan that will be amortized from accumulated other comprehensive income into net periodic benefit cost over the next year are $nil and $nil respectively.

Amounts recognized in accumulated other comprehensive income that have not yet been recognized as components of net periodic benefit cost are as follows:

		December 31, 2015		December 31, 2014		December 31, 2013
		(in thousands)
Net actuarial loss	$	2,281	$	6,113	$	1,988
Total	$	2,281	$	6,113	$	1,988

Benefit Obligation

The following assumptions were used in determining the benefit obligation at December 31, 2015:

	December 31,			December 31,
	2015			2014
Discount rate		4.0	%		3.6	%
Rate of compensation increase		3.7	%		3.6	%

The discount rate is determined by reference to UK long dated government and corporate bond yields at the balance sheet date. This is represented by the iboxx corporate bond over 15 year index plus 30 basis points.

Plan Assets

The assets of the scheme are invested with Legal and General and held in a combination of the Active Corporate Bond over 10 Year fund, Gilt, and Index Linked Gilt funds. The overall investment strategy is that approximately 70% of investments are in government bonds (both fixed interest and index linked) and approximately 30% of investments are held in corporate bonds. There is no self-investment in employer related assets. The expected long-term rate of return on assets at December 31, 2015 of 3.0% was calculated as the value of the fund after application of a market value reduction factor. The expected long term rates of return on different asset classes are as follows:

Asset Category	Expected long-term return per annum
Corporate Bonds		4.0	%
Gilts		2.6	%

The long-term expected return on corporate bonds and gilts (fixed interest and index linked) is determined by reference to bond yields and gilt yields at the balance sheet date.

The underlying asset split of the fund is shown below.

Asset Category	December 31, 2015			December 31, 2014
Corporate Bonds		26	%		26	%
Gilts		74	%		74	%
		100	%		100	%

Applying the above expected long term rates of return to the asset distribution at December 31, 2015, gives rise to an expected overall rate of return of scheme assets of approximately 3.0% per annum.

Plan Asset Fair Value Measurements

	Quoted Prices in Active Markets for Identical Assets Level 1 (in thousands)
	December 31, 2015		December 31, 2014
Cash	$	3	$	16

Fixed Income Securities
Legal and General Active Corporate Bond – Over 10 Year		6,256		6,560
Legal and General Gilt Funds		6,528		6,977
Legal and General Index Linked Gilt Funds		10,580		11,856
	$	23,367	$	25,409

Cash Flows

The Company expects to contribute $0.1 million to its pension fund in the year ending December 31, 2016.

The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid.

	(in thousands)

2016		66
2017		68
2018		71
2019		72
2020		75
Years 2021 - 2025	$	376

The expected cash flows are estimated figures based on the members expected to retire over the next 10 years assuming no early retirements plus an additional amount in respect of recent average withdrawal experience. At the present time it is not clear whether annuities will be purchased when members reach retirement or whether pensions will be paid each month out of scheme assets. The cash flows above have been estimated on the assumption that pensions will be paid monthly out of scheme assets. If annuities are purchased, then the expected benefit payments will be significantly different from those shown above.

On May 7, 2014 the Company acquired 100% of the common stock of Aptiv Solutions (“Aptiv”). The acquisition of Aptiv was accounted for as a business combination in accordance with FASB ASC 805 Business Combinations. The Company has a defined benefit plan covering its employees in Switzerland as mandated by the Swiss government. Benefits are based on the employee’s years of service and compensation. Benefits are paid directly by the Company when they become due, in conformity with the funding requirements of applicable government regulations. The plan is managed externally and the related pension costs and liabilities are assessed in accordance with the advice of a professionally qualified actuary. Plan assets at December 31, 2015 and December 31, 2014 consist of units held in independently administered funds. The pension costs of this plan are presented in the following tables in accordance with the requirements of ASC 715-60, Defined Benefit Plans – Other Postretirement.

Change in benefit obligation	December 31, 2015
	(in thousands)

Benefit obligation at beginning of year		8,884
Service cost		618
Interest cost		159
Actuarial loss		81
Foreign currency exchange rate changes		(1,205	)
Benefit obligation at end of year		8,537

Change in plan assets

Fair value of plan assets at beginning of year	7,061
Expected return on plan assets	93
Actual return on plan assets	(1,075	)
Scheme contributions	194
Plan participants’ contributions	216
Benefits paid	(1,146	)
Foreign currency exchange rate changes	7
Fair value of plan assets at end of year	5,350

The fair values of the assets above do not include any of the Company’s own financial instruments, property occupied by, or other assets used by, the Company.

Funded status	December 31, 2015
	(in thousands)
Projected benefit obligation	$	8,537
Fair value of plan assets		(5,350	)
Funded status		3,187

Non-current other liabilities (note 8)		3,187

	December 31, 2015
	(in thousands)
Service cost	$	402
Interest cost		159
Expected return on plan assets		(119	)
Settlement loss		18
Net periodic benefit cost	$	460

The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the year ended December 31, 2015:

	December 31,
	2015
Discount rate		1.35	%
Rate of compensation increase		2.0	%
Expected rate of return on plan assets		1.35	%

Accumulated other comprehensive income	December 31, 2015
Actuarial loss - benefit obligation	$	81
Actuarial (gain) – plan assets		1,075
Prior service cost recognized in net periodic benefit cost		(17	)
Total	$	1,139

Benefit Obligation

The following assumptions were used in determining the benefit obligation at December 31, 2015:

	December 31,
	2015
Discount rate		0.95	%
Rate of compensation increase		2.0	%

The discount rate is determined by reference to Swiss long dated government and corporate bond yields at the balance sheet date.

Plan Assets

The assets of the scheme are invested with Swiss Life and held in a combination of debt securities, equity securities and in real estate. There is no self-investment in employer related assets. The expected long term rates of return on different asset classes are as follows:

Asset Category	December 31, 2015
Equity securities		1	%
Debt securities		75	%
Real estate		12	%
Other		12	%
		100	%

Cash Flows

The Company expects to contribute $0.2 million to its pension fund in the year ending December 31, 2016.

The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid.

	(in thousands)

2016		166
2017		169
2018		171
2019		182
2020		182
Years 2021 - 2025	$	1,205

Equity Incentive Schemes and Stock Compensation Charges

12 Months Ended

Dec. 31, 2015

Equity Incentive Schemes and Stock Compensation Charges

10. Equity Incentive Schemes and Stock Compensation Charges

Share Options

On July 21, 2008 the Company adopted the Employee Share Option Plan 2008 (the “2008 Employee Plan”) pursuant to which the Compensation and Organization Committee of the Company’s Board of Directors may grant options to any employee, or any Director holding a salaried office or employment with the Company or a Subsidiary for the purchase of ordinary shares. On the same date, the Company also adopted the Consultants Share Option Plan 2008 (the “2008 Consultants Plan”), pursuant to which the Compensation and Organization Committee of the Company’s Board of Directors may grant options to any consultant, adviser or non-executive Director retained by the Company or any Subsidiary for the purchase of ordinary shares.

Each option granted under the 2008 Employee Plan or the 2008 Consultants Plan (together the “2008 Option Plans”) will be an employee stock option, or NSO, as described in Section 422 or 423 of the Internal Revenue Code. Each grant of an option under the 2008 Options Plans will be evidenced by a Stock Option Agreement between the optionee and the Company. The exercise price will be specified in each Stock Option Agreement, however option prices will not be less than 100% of the fair market value of an ordinary share on the date the option is granted.

An aggregate of 6.0 million ordinary shares have been reserved under the 2008 Employee Plan, as reduced by any shares issued or to be issued pursuant to options granted under the 2008 Consultants Plan, under which a limit of 400,000 shares applies. Further, the maximum number of ordinary shares with respect to which options may be granted under the 2008 Employee Option Plan, during any calendar year to any employee shall be 400,000 ordinary shares. There is no individual limit under the 2008 Consultants Plan. No options may be granted under the 2008 Option Plans after July 21, 2018.

On January 17, 2003 the Company adopted the Share Option Plan 2003 (the “2003 Share Option Plan”) pursuant to which the Compensation and Organization Committee of the Board could grant options to officers and other employees of the Company or its subsidiaries for the purchase of ordinary shares. An aggregate of 6.0 million ordinary shares were reserved under the 2003 Share Option Plan; and, in no event could the number of ordinary shares issued pursuant to options awarded under this plan exceed 10% of the outstanding shares, as defined in the 2003 Share Option Plan, at the time of the grant, unless the Board expressly determined otherwise. Further, the maximum number of ordinary shares with respect to which options could be granted under the 2003 Share Option Plan during any calendar year to any employee was 400,000 ordinary shares. The 2003 Share Option Plan expired on January 17, 2013. No new options may be granted under this plan.

Share option awards are granted with an exercise price equal to the market price of the Company’s shares at date of grant. Share options typically vest over a period of five years from date of grant and expire eight years from date of grant. The maximum contractual term of options outstanding at December 31, 2015 is eight years.

The following table summarizes the transactions for the Company’s share option plans for the years ended December 31, 2015, December 31, 2014 and December 31, 2013:

	Options Granted Under Plans			Number of Shares			Weighted Average Exercise Price		Weighted Average Grant Date Fair Value
Outstanding at December 31, 2012		4,350,631			4,350,631		$	23.01	$	9.17
Granted		264,950			264,950		$	33.09	$	12.05
Exercised		(1,249,759	)		(1,249,759	)	$	21.60	$	8.58
Cancelled		(392,034	)		(392,034	)	$	25.27	$	10.02
Outstanding at December 31, 2013		2,973,788			2,973,788		$	24.20	$	9.57
Granted		366,985			366,985		$	45.82	$	14.09
Exercised		(926,407	)		(926,407	)	$	24.02	$	9.45
Cancelled		(186,666	)		(186,666	)	$	22.17	$	9.01
Outstanding at December 31, 2014		2,227,700			2,227,700		$	28.00	$	10.40
Granted		259,059			259,059		$	68.25	$	19.75
Exercised		(773,753	)		(773,753	)	$	27.13	$	10.31
Cancelled		(86,424	)		(86,424	)	$	27.32	$	10.31
Outstanding at December 31, 2015		1,626,582			1,626,582		$	34.87	$	11.94
Vested and exercisable at December 31, 2015		657,729			657,729		$	24.15	$	9.36

The weighted average remaining contractual life of options outstanding and options exercisable at December 31, 2015, was 4.76 years and 3.39 years respectively (2014: 4.58 years and 3.22 years respectively). 336,993 options are expected to vest during the year ended December 31, 2016 (494,951 options were expected to vest during the year ended December 31, 2015).

The intrinsic value of options exercised during the year ended December 31, 2015 amounted to $34.2 million. The intrinsic value of options outstanding and options exercisable at December 31, 2015 amounted to $69.7 million and $35.2 million respectively. Intrinsic value is calculated based on the market value versus strike price of the Company’s shares at the date of exercise.

Non-vested shares outstanding as at December 31, 2015 are as follows:

	Options Outstanding Number of Shares			Weighted Average Exercise Price		Weighted Average Fair Value

Non-vested outstanding at December 31, 2014		1,203,150		$	30.54	$	10.98

Granted		259,059			68.25		19.75
Vested		(379,992	)		28.25		10.49
Forfeited		(113,364	)		25.21		9.50

Non-vested outstanding at December 31, 2015		968,853		$	42.14	$	13.69

Outstanding and exercisable share options:

The following table summarizes information concerning outstanding and exercisable share options as of December 31, 2015:

Options Outstanding								Options Exercisable
Range Exercise Price		Number of Shares		Weighted Average Remaining Contractual Life		Weighted Average Exercise Price		Number of Shares		Weighted Average Exercise Price
$	15.84		50,000		1.33	$	15.84		50,000	$	15.84
$	16.80		60,000		3.83	$	16.80		30,000	$	16.80
$	17.17		12,000		3.85	$	17.17		6,000	$	17.17
$	18.98		600		0.87	$	18.98		600	$	18.98
$	20.16		400		2.88	$	20.16		400	$	20.16
$	20.28		255,694		3.17	$	20.28		158,073	$	20.28
$	20.59		57,200		4.14	$	20.59		4,000	$	20.59
$	22.26		61,755		1.15	$	22.26		61,755	$	22.26
$	22.30		250,939		4.32	$	22.30		109,894	$	22.30
$	23.66		7,890		4.58	$	23.66		4,450	$	23.66
$	24.46		101,412		2.18	$	24.46		101,412	$	24.46
$	26.20		1,950		2.39	$	26.20		1,950	$	26.20
$	26.71		4,450		4.86	$	26.71		2,670	$	26.71
$	29.45		3,000		2.33	$	29.45		3,000	$	29.45
$	32.37		179,603		5.34	$	32.37		70,997	$	32.37
$	35.33		1,350		0.16	$	35.33		1,350	$	35.33
$	36.22		27,213		5.47	$	36.22		7,908	$	36.22
$	37.90		7,100		5.93	$	37.90		920	$	37.90
$	40.83		105,992		6.40	$	40.83		20,468	$	40.83
$	47.03		71,670		6.18	$	47.03		7,520	$	47.03
$	48.67		140,881		6.21	$	48.67		13,556	$	48.67
$	51.35		4,030		6.61	$	51.35		806	$	51.35
$	66.47		15,969		7.39	$	66.47		-	$	66.47
$	66.97		3,118		7.46	$	66.97		-	$	66.97
$	68.39		232,366		7.22	$	68.39		-	$	68.39

$	15.84 - $68.39		1,626,582		4.76	$	34.87		657,729	$	24.15

Options outstanding include both vested and unvested options as at December 31, 2015. Options exercisable represent options which have vested at December 31, 2015. From the date of grant, substantially all options vest over a five year period at 20% per annum.

Fair value of Stock Options Assumptions

The weighted average fair value of options granted during the years ended December 31, 2015, December 31, 2014 and December 31, 2013 was calculated using the Black-Scholes option pricing model. The weighted average fair values and assumptions were as follows:

	Year Ended
	December 31,			December 31,			December 31,
	2015			2014			2013

Weighted average fair value	$	19.75		$	14.09		$	12.05

Assumptions:
Expected volatility		30	%		32	%		40	%
Dividend yield		0	%		0	%		0	%
Risk-free interest rate		1.58	%		1.57	%		0.76	%
Expected life	5.0 years			5.0 years			5.0 years

Expected volatility is based on the historical volatility of our common stock over a period equal to the expected term of the options; the expected life represents the weighted average period of time that options granted are expected to be outstanding given consideration to vesting schedules, and our historical experience of past vesting and termination patterns. The risk-free rate is based on the U.S. government zero-coupon bonds yield curve in effect at time of the grant for periods corresponding with the expected life of the option.

Restricted Share Units and Performance Share Units

On July 21, 2008 the Company adopted the 2008 Employees Restricted Share Unit Plan (the “2008 RSU Plan”) pursuant to which the Compensation and Organization Committee of the Company’s Board of Directors may select any employee, or any Director holding a salaried office or employment with the Company, or a Subsidiary to receive an award under the plan. An aggregate of 1.0 million ordinary shares have been reserved for issuance under the 2008 RSU Plan.

On April 23, 2013 the Company adopted the 2013 Employees Restricted Share Unit and Performance Share Unit Plan (the “2013 RSU Plan”) pursuant to which the Compensation and Organization Committee of the Company’s Board of Directors may select any employee, or any Director holding a salaried office or employment with the Company, or a Subsidiary to receive an award under the plan. On May 11, 2015 the 2013 RSU Plan was amended and restated in order to increase the number of shares that can be issued under the RSU Plan by 2.5 million shares. Accordingly, an aggregate of 4.1 million ordinary shares have been reserved for issuance under the 2013 RSU Plan. The shares are awarded at par value and vest over a service period. Awards under the 2013 RSU Plan may be settled in cash or shares at the option of the Company.

The Company has awarded RSU’s and PSU’s to certain key individuals of the Group. The following table summarizes RSU and PSU activity for the year ended December 31, 2015:

	PSU Outstanding Number of Shares			PSU Weighted Average Fair Value		PSU Weighted Average Remaining Contractual Life		RSU Outstanding Number of Shares			RSU Weighted Average Fair Value		RSU Weighted Average Remaining Contractual Life


Outstanding at December 31, 2014		669,171		$	39.78		1.77		1,038,996		$	35.19		1.67

Granted		259,110		$	68.82				389,542		$	67.02
Shares vested		(7,990	)		32.38				(268,870	)	$	26.06
Forfeited		(18,518	)	$	46.82				(92,055	)	$	44.43

Outstanding at December 31, 2015		901,773		$	72.55		2.49		1,067,613		$	48.30		1.48

The fair value of RSU’s vested for the year ended December 31, 2015 totaled $7.0 million (2014: $4.9 million).

The fair value of PSU’s vested for the year ended December 31, 2015 totaled $0.3 million. No PSU’s vested during 2014.

The PSU’s vest based on service and specified EPS targets over the periods 2014 – 2016 and 2015 – 2017. Since 2013, 456,922 PSU’s (net of forfeitures and exercises) have been granted. Depending on the actual amount of EPS from 2013 to 2017, up to an additional 444,851 PSU’s may also be granted.

Non-cash stock compensation expense

Income from operations for the year ended December 31, 2015 is stated after charging $33.3 million in respect of non-cash stock compensation expense. Non-cash stock compensation expense for the year ended December 31, 2015 has been allocated as follows:

	Year ended
	December 31, 2015		December 31, 2014		December 31, 2013
	(in thousands)
Direct costs	$	18,358	$	12,531	$	7,835
Selling, general and administrative	$	14,959	$	10,211	$	6,385
Total compensation costs	$	33,317	$	22,742	$	14,220

Total non-cash stock compensation expense not yet recognized at December 31, 2015 amounted to $61.9 million. The weighted average period over which this is expected to be recognized is 2.05 years. Total tax benefit recognized in additional paid in capital related to the non-cash compensation expense amounted to $1.9 million for the year ended December 31, 2015 (2014: $2.4 million, 2013: $1.7 million).

The income tax expense for the year ended December 31, 2015 reflects a net income tax benefit of $1.5 million in connection with stock compensation and the cash tax benefit realized in connection with stock options exercised during 2015 was $5.6 million. The income tax expense for the year ended 31 December 2014 reflects a net income tax benefit of $1.5 million in connection with stock compensation and the cash tax benefit realized in connection with stock options exercised during 2014 was $3.9 million.

Share Capital

12 Months Ended

Dec. 31, 2015

Share Capital

12. Share Capital

Holders of ordinary shares will be entitled to receive such dividends as may be recommended by the Board of Directors of the Company and approved by the shareholders and/or such interim dividends as the Board of Directors of the Company may decide. On liquidation or a winding up of the Company, the par value of the ordinary shares will be repaid out of the assets available for distribution among the holders of the ordinary shares of the Company. Holders of ordinary shares have no conversion or redemption rights. On a show of hands, every holder of an ordinary share present in person or proxy at a general meeting of shareholders shall have one vote, for each ordinary share held with no individual having more than one vote.

During the year ended December 31, 2015, 773,753 options were exercised by employees at an average exercise price of $27.13 per share for total proceeds of $21.0 million. During the year ended December 31, 2015, 268,870 ordinary shares were issued in respect of certain RSU’s and 7,990 ordinary shares were issued in respect of certain PSUs previously awarded by the Company.

During the year ended December 31, 2014, 926,407 options were exercised by employees at an average exercise price of $24.02 per share for total proceeds of $22.3 million. During the year ended December 31, 2014, 233,726 ordinary shares were issued in respect of certain RSU’s previously awarded by the Company.

During the year ended December 31, 2013, 1,249,759 options were exercised by employees at an average exercise price of $21.60 per share for total proceeds of $27.0 million. During the year ended December 31, 2013, 50,000 ordinary shares were issued in respect of certain RSU’s previously awarded by the Company.

(a) Share Repurchase Program

On May 1, 2015 the Company commenced a buyback program of up to $60 million under which the Company could acquire its outstanding ordinary shares (by way of redemption), in accordance with Irish law, the United States securities laws and the Company’s constitutional documents through open market share acquisitions. A total of 882,419 ordinary shares were redeemed by the Company under this buyback program for a total consideration of $57.9 million. All ordinary shares that were redeemed under the buyback program were cancelled in accordance with the Constitution of the Company and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law.

On July 31, 2015 the Company commenced a further buyback program of up to $400 million under which the Company could acquire its outstanding ordinary shares (by way of redemption), in accordance with Irish law, the United States securities laws and the Company’s constitutional documents through open market share acquisitions. A total of 5,316,062 ordinary shares were redeemed by the Company under this buyback program for a total consideration of $400 million. All ordinary shares that were redeemed under the buyback program were cancelled in accordance with the Constitution of the Company and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law. The share buyback program was completed in December 2015, with a total of 6,198,481 ordinary shares redeemed during the year ended December 31, 2015 for total consideration of $457.9 million.

During the year ended December 31, 2014 2,640,610 ordinary shares were repurchased by the Company for a total consideration of $140.0 million. There were no share repurchases completed during 2013. All ordinary shares repurchased by the Company were cancelled, and the nominal value of these shares transferred to a capital redemption reserve fund as required under Irish Company Law.

On October 27, 2011 the Company announced its intention to commence a share repurchase program of up to $50 million. On November 22, 2011 the Company entered into two separate share repurchase plans of up to $10 million each, covering the periods November 23, 2011 to December 31, 2011 and January 1, 2012 to February 20, 2012 respectively. On February 21, 2012 the Company entered into a further share repurchase plan of up to $20 million, covering the period February 22, 2012 to April 22, 2012. On April 27, 2012 the Company entered into a fourth share repurchase plan of up to $20 million, covering the period April 27, 2012 to July 18, 2012. On July 30, 2012 the Company entered into a fifth share repurchase plan of up to $10 million, covering the period July 30, 2012 to October 26, 2012. On September 19, 2014 the Company announced that it had completed a $40 million redemption of the Company’s ordinary shares and that it had entered into a further program under which the Company can acquire up to an additional $100 million of its outstanding ordinary shares (by way of redemption), in accordance with United States securities laws through open market share acquisitions.

Under the repurchase program, a broker purchased the Company’s shares from time to time on the open market or in privately negotiated transactions in accordance with agreed terms and limitations. The program was designed to allow share repurchases during periods when the Company would ordinarily not be permitted to do so because it may be in possession of material non-public or price-sensitive information, applicable insider trading laws or self-imposed trading blackout periods. The Company’s instructions to the broker were irrevocable and the trading decisions in respect of the repurchase program were made independently of and uninfluenced by the Company. The Company confirms that on entering the share repurchase plans it had no material non-public, price-sensitive or inside information regarding the Company or its securities. Furthermore, the Company will not enter into additional plans whilst in possession of such information. The timing and actual number of shares acquired by way of the redemption will be dependent on market conditions, legal and regulatory requirements and the other terms and limitations contained in the program. In addition, acquisitions under the program may be suspended or discontinued in certain circumstances in accordance with the agreed terms. Therefore, there can be no assurance as to the timing or number of shares that may be acquired under the program.

- Definition

The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d),(e))
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 4: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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Reference 8: http://www.xbrl.org/2003/role/presentationRef
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Reference 9: http://www.xbrl.org/2003/role/presentationRef
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Reference 10: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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Reference 11: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 12: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 4
-Section E

Reference 15: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
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+ Details

Income Taxes

12 Months Ended

Dec. 31, 2015

Income Taxes

13. Income Taxes

The Company’s United States and Irish based subsidiaries file tax returns in the United States and Ireland respectively. Other foreign subsidiaries are taxed separately under the laws of their respective countries.

The components of income before provision for income taxes are as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	184,643	$	143,889	$	80,914
United States		15,436		6,966		16,218
Other		78,771		51,861		23,733
Income before provision for income taxes	$	278,850	$	202,716	$	120,865

The components of provision for income taxes are as follows:

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Provision for income taxes:
Current tax expense:
Ireland	$	21,769		$	19,562		$	9,158
United States		684			7,891			14,492
Other		13,701			10,695			4,876
Total current tax expense		36,154			38,148			28,526

Deferred tax expense/(benefit):
Ireland		26			(1,178	)		1,914
United States		2,896			(3,031	)		(9,420	)
Other		235			(3,691	)		(2,967	)
Total deferred tax expense/(benefit)		3,157			(7,900	)		(10,473	)

Provision for income taxes		39,311			30,248			18,053

Impact on shareholders equity and other comprehensive income of the tax consequence of :
Excess tax benefit on stock compensation		(1,905	)		(2,404	)		(1,651	)
Currency impact on long term funding		3,574			178			87

Total	$	40,980		$	28,022		$	16,489

Ireland’s statutory income tax rate is 12.5%. The Company’s consolidated reported provision for income taxes differed from the amount that would result from applying the Irish statutory rate as set forth below:

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Taxes at Irish statutory rate of 12.5% (2014:12.5%; 2013:12.5%)	$	34,856		$	25,340		$	15,108
Foreign and other income taxed at higher rates		4,614			3,152			4,873
Research & development tax incentives		(695	)		(1,810	)		(2,598	)
Movement in valuation allowance		(4,133	)		(1,965	)		2,389
Effects of change in tax rates		(16	)		543			1,553
Increase/(decrease) in unrecognized tax benefits		5,085			2,869			(1,409	)
Effects of permanent items		(463	)		2,048			(1,790	)
Other		63			71			(73	)
Provision for income taxes	$	39,311		$	30,248		$	18,053

The tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities are presented below:

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Deferred tax liabilities:
Property, plant and equipment	$	2,665		$	4,270		$	6,501
Goodwill		21,571			18,645			14,013
Other intangible assets		7,369			3,657			970
Other		1,293			1,947			1,111
Total deferred tax liabilities recognized		32,898			28,519			22,595

Deferred tax assets:
Operating loss and tax credits carryforwards		22,186			30,586			29,696
Property, plant and equipment		4,818			4,002			2,739
Accrued expenses and payments on account		29,473			37,620			30,136
Stock compensation		12,959			8,717			6,291
Deferred compensation expense		2,174			1,853			1,187
Other		566			1,244			92
Total deferred tax assets		72,176			84,022			70,141
Valuation allowance for deferred tax assets		(17,184	)		(23,145	)		(24,348	)
Deferred tax assets recognized		54,992			60,877			45,793
Overall net deferred tax asset	$	22,094		$	32,358		$	23,198

The Company early adopted the provisions of ASU 2015-17 which requires entities with a classified balance sheet to present all deferred tax assets and liabilities as noncurrent on the basis that it is a more useful presentation of the Company’s position. The prior period amounts were not retrospectively adjusted.

At December 31, 2015 non-U.S subsidiaries had operating loss carryforwards for income tax purposes that may be carried forward indefinitely, available to offset against future taxable income, if any, of approximately $68.6 million (2014: $95.6 million). In addition at December 31, 2015 non-U.S subsidiaries had tax credit carryforwards for income tax purposes that may be carried forward indefinitely, available to offset against future tax liabilities, if any, of $5.9 million (2014: $3.6 million). At December 31, 2015 non-U.S. subsidiaries also had additional operating loss carry forwards of $6.3 million which are due to expire between 2016 and 2022.

At December 31, 2015 U.S. subsidiaries had U.S. federal and state net operating loss (“NOL”) carry forwards of approximately $51.6million and $ 89.8million, respectively. These NOLs are available for offset against future taxable income and expire between 2016 and 2035. Of the $51.6 million U.S. federal NOLs, approximately $ 26.7 million is currently available for offset against future U.S. federal taxable income. Of the $51.6 million U.S. federal NOLs, approximately $ 16.3million would be recorded in additional paid in capital upon utilization. Of the $89.8 million of state NOLs, approximately $ 17.3million would be recorded in additional paid in capital upon utilization. The subsidiary’s ability to use the U.S. federal and state NOL carry forwards is limited on an annual basis due to changes of ownership in 2000, 2010 and 2014, as defined by Section 382 of the Internal Revenue Code of 1986, as amended. Of the U.S. federal NOLs, $29.2 million are limited by Section 382. Of the $29.2 million of losses, the amount available during 2015 totaled $4.2 million. The remaining losses are available as follows: $4.2 million for the years 2016 – 2018, $2.9 million in 2019, $2.0M for the years 2020 – 2023 and $1.2 million in 2024.

The expected expiry dates of these losses are as follows:

	Federal NOL’s		State NOL’s
	(in thousands)

2016-2017		565		-
2023-2033		34,800		63,793
2035		16,252		25,987

	$	51,617	$	89,780

In addition US subsidiaries have alternative minimum tax credit carry forwards of approximately $0.3 million that are available to reduce future U.S. federal regular income taxes, over an indefinite period. They also have general business credit carry forwards of approximately $0.3 million that are available to offset future U.S. federal income taxes.

The valuation allowance at December 31, 2015 was approximately $17.2 million. The valuation allowance for deferred tax assets as of December 31, 2014 and December 31, 2013 was $23.1 million and $24.3 million respectively. The net change in the total valuation allowance was a decrease of $5.9 million during 2015 and a decrease of $1.2 million during 2014. Of the total decrease of $5.9 million in 2015, $4.1 million resulted in a current year income tax benefit with the remaining decrease of $1.8 million recognized in Other Comprehensive Income. Of the total decrease of $1.2 million in 2014, $2.0 million resulted in a current year income tax benefit offset by an increase of $0.8 million recognized in Other Comprehensive Income.

The valuation allowances at December 31, 2015 and December 31, 2014 were primarily related to operating losses and tax credits carried forward that, in the judgment of management, are not more likely than not to be realized. In assessing the realizability of deferred tax assets, management considers whether it is more likely than not that some portion or all of the deferred tax assets will not be realized. The ultimate realization of deferred tax assets is dependent upon the generation of future taxable income during the periods in which those temporary differences become deductible. Management considers the scheduled reversal of deferred tax liabilities and projected future taxable income in making this assessment. In respect of deferred tax assets not subject to a valuation allowance, Management considers that it is more likely than not that these deferred tax assets will be realized on the basis that there will be sufficient reversals of deferred tax liabilities and taxable income in future periods. In 2014, in the UK, a change in commercial circumstances led to a change in judgment concerning the need for a valuation allowance on certain limited loss carryforwards; the release of the beginning-of-year valuation allowance resulted in a tax benefit of $3.1 million. During 2015, a UK subsidiary utilized losses for which a full beginning-of-year valuation allowance had been retained resulting in a tax benefit of $3.2 million.

The Company has not recognized a deferred tax liability for the undistributed earnings of foreign subsidiaries that arose in 2015 and prior years as the Company considers these earnings to be indefinitely reinvested. It is not practicable to calculate the exact unrecognized deferred tax liability, however it is not expected to be material as Ireland allows a tax credit in respect of distributions from foreign subsidiaries at the statutory tax rate in the jurisdiction of the subsidiary so that no material tax liability would be expected to arise in the event these earnings were ever remitted. In addition, withholding taxes applicable to remittances from foreign subsidiaries would not be expected to be material given Ireland’s tax treaty network and the EU parent subsidiary directive.

A reconciliation of the beginning and ending amount of total unrecognized tax benefits is as follows:

	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Unrecognized tax benefits at start of year	$	23,201		$	5,780		$	7,189


Increase related to acquired tax positions		778			14,552			-
Increase related to prior year tax positions		1,482			565			-
Decrease related to prior year tax positions		-			(183	)		(494	)
Increase related to current year tax positions		3,063			3,709			2,269
Settlements		(315	)		(2	)		(899	)
Lapse of statute of limitations		(43	)		(1,220	)		(2,285	)
Unrecognized tax benefits at end of year	$	28,166		$	23,201		$	5,780

The relevant statute of limitations for unrecognized tax benefits totaling $3.8 million could potentially expire during 2016. $0.8 million of the increase during the year ended 31 December 2015 (2014: $14.5 million) reflects pre-acquisition tax positions taken by companies acquired during 2014.

Included in the balance of total unrecognized tax benefits at December 31, 2015 were potential benefits of $28.2 million, which if recognized, would affect the effective rate on income tax from continuing operations. The balance of total unrecognized tax benefits at December 31, 2014 and December 31, 2013 included potential benefits which, if recognized, would affect the effective rate of income tax from continuing operations of $23.2 million and $5.8 million respectively.

Interest and penalties recognized as a net expense during the year ended December 31, 2015 amounted to $0.9 million (2014: net benefit of $0.2 million, 2013: net benefit of $0.2 million) and are included within the provision for income taxes. Total accrued interest and penalties as of December 31, 2015 and December 31, 2014 were $3.3 million and $2.4 million respectively and are included in closing income taxes payable at those dates.

Our major tax jurisdictions are the United States and Ireland. We may potentially be subjected to tax audits in both our major jurisdictions. In the United States tax periods open to audit include the years ended December 31, 2012, December 31, 2013, December 31, 2014 and December 31, 2015. In Ireland, tax periods open to audit include the years ended December 31, 2011, December 31, 2012, December 31, 2013, December 31, 2014 and December 31, 2015. During such audits, local tax authorities may challenge the positions taken by us in tax returns.

Restructuring and other items

12 Months Ended

Dec. 31, 2015

Restructuring and other items

14. Restructuring and other items

Restructuring and other items recognized during the year ended December 31, 2015 comprise:

	Year Ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Restructuring charges		-	$	8,796	$	9,033
Net charge		-	$	8,796	$	9,033

Prior Period Restructuring Charges

A restructuring charge of $8.8 million was recognized during the year ended December 31, 2014. Following the closure of the Company’s European Phase 1 services in 2013, the Company recognized a charge in 2014 in relation to its Manchester, United Kingdom facility; $5.6 million in relation to asset impairments and $3.2 million in relation to an onerous lease charge associated with this facility. We expect this to be paid by 2024.

	Onerous			Asset
	Lease			Impairment			Total
	(in thousands)

Total provision recognized	$	3,167		$	5,629		$	8,796
Asset write-off		-			(5,629	)		(5,629	)
Provision at December 31, 2014	$	3,167			-		$	3,167
Utilized		(1,167	)		-			(1,167	)
Provision at December 31, 2015		2,000			-			2,000

The onerous lease obligation at December 31, 2015 is $2.0 million and is included within other liabilities.

Prior Period Restructuring Charges

Restructuring and other items of $9.0 million were recorded during the year ended December 31, 2013. During 2013 the Company conducted a review of its operations. This review resulted in the adoption of an initial restructuring plan, which included the closure of its Phase I facility in Omaha, Nebraska. This followed the expansion of the Company’s Phase I facility in San Antonio, Texas and the consolidation of the Company’s US Phase I capabilities in this location. The restructuring plan also included resource rationalizations in certain areas of the business to improve resource utilization. A further restructuring plan was also adopted during 2013 which resulted in resource rationalizations in order to improve operating efficiencies and reduce expenses. Details of the movement in this restructuring plan are as follows:

	Workforce			Office
	Reductions			Consolidations			Total
	(in thousands)

Q1 Plan - Initial provision recognized	$	3,903		$	509		$	4,412
Q2 Plan - Initial provision recognized		4,228			393			4,621
Total provision recognized		8,131			902			9,033
Cash payments		(6,544	)		(199	)		(6,743	)
Amounts released		(93	)		-			(93	)
Foreign exchange movement		(3	)		-			(3	)
Provision at December 31, 2013	$	1,491		$	703		$	2,194
Cash payments		(1,319	)		(337	)		(1,656	)
Amounts released		-			-			-
Foreign exchange movement		(1	)		-			(1	)
Provision at December 31, 2014	$	171		$	366		$	537
Cash payments		(82	)		-			(82	)
Amounts released		-			(339	)		(339	)
Provision at December 31, 2015	$	89		$	27		$	116

Commitments and Contingencies

12 Months Ended

Dec. 31, 2015

Commitments and Contingencies

16. Commitments and Contingencies

Litigation

The Company is not party to any litigation or other legal proceedings that the Company believes could reasonably be expected to have a material adverse effect on the Company's business, results of operations and financial condition.

Operating Leases

The Company has several non-cancelable operating leases, primarily for facilities, that expire over the next 10 years. These leases generally contain renewal options and require the Company to pay all executory costs such as maintenance and insurance. The Company recognized $49.9 million, $54.3 million and $54.9 million in rental expense, including rates, for the years ended December 31, 2015, December 31, 2014 and December 31, 2013 respectively. Future minimum rental commitments for operating leases with non-cancelable terms in excess of one year are as follows:

	Minimum rental payments
	(in thousands)
2016		36,921
2017		26,784
2018		20,547
2019		15,502
2020		11,974
Thereafter		45,924

Total	$	157,652

Business Segment and Geographical Information

12 Months Ended

Dec. 31, 2015

Business Segment and Geographical Information

17. Business Segment and Geographical Information

The Company is a contract research organization (“CRO”), providing outsourced development services on a global basis to the pharmaceutical, biotechnology and medical device industries. It specializes in the strategic development, management and analysis of programs that support all stages of the clinical development process - from compound selection to Phase I-IV clinical studies. The Company has the expertise and capability to conduct clinical trials in most major therapeutic areas on a global basis and has the operational flexibility to provide development services on a stand-alone basis or as part of an integrated “full service” solution. The Company has expanded predominately through internal growth, together with a number of strategic acquisitions to enhance its expertise and capabilities in certain areas of the clinical development process.

The Company determines and presents operating segments based on the information that is internally provided to the Chief Executive Officer, Chief Financial Officer and Chief Operating Officer, who together are considered the Company’s chief operating decision maker, in accordance with FASB ASC 280-10 Disclosures about Segments of an Enterprises and Related Information.

Revenues are allocated to individual entities based on where the work is performed in accordance with the Company’s global transfer pricing model. Revenues and income from operations in Ireland are a function of this transfer pricing model.

Given ICON Clinical Research Limited (“ICON Ireland”) role in the development and management of the group, it’s ownership of key intellectual property, customer relationships, its key role in the mitigation of risks faced by the group, plus the responsibility for maintaining the group’s global network, ICON Ireland acts as the group entrepreneur and enters into the majority of the Company’s customer contracts. As such, ICON Ireland remunerates most of the other operating entities (“cost plus service providers”) in the ICON Group on the basis of a guaranteed cost plus mark up for the services they perform in each of their local territories.

The cost plus mark up for each ICON entity is established to ensure that each of ICON Ireland and the ICON entities in the various geographical areas that are involved in the conduct of services for customers, earn an appropriate arms-length return having regard to the assets owned, risks borne, and functions performed by each entity from these intercompany transactions. The cost plus mark-up policy is reviewed annually to ensure that it is market appropriate.

Under this method, the residual operating profits (or losses) of the group, once the cost plus service providers have been paid their respective intercompany service fee, generally fall to be retained by ICON Ireland. The geographic split of revenue disclosed for each region outside Ireland is the cost plus revenue attributable to these entities. The revenues disclosed as relating to Ireland are the net revenues after deducting the cost plus revenues attributable to the activities performed outside Ireland.

The Company's areas of operation outside of Ireland include the United States, United Kingdom, France, Germany, Italy, Spain, The Netherlands, Sweden, Turkey, Poland, Czech Republic, Latvia, Russia, Ukraine, Hungary, Israel, Romania, Switzerland, Canada, Mexico, Brazil, Colombia, Argentina, Chile, Peru, India, China, South Korea, Japan, Thailand, Taiwan, Singapore, The Philippines, Australia, New Zealand, and South Africa.

Business segment and geographical information as at December 31, 2015 and December 31, 2014 and for the years ended December 31, 2015, December 31, 2014 and December 31, 2013 is as follows:

a) The distribution of net revenue by geographical area was as follows:

		Year ended
		December 31, 2015		December 31, 2014		December 31, 2013
		(in thousands)
Ireland	$	429,631	$	360,376	$	272,683
Rest of Europe		330,487		372,634		333,543
U.S.		650,941		605,815		582,250
Other		163,919		164,491		147,582
Total	$	1,574,978	$	1,503,316	$	1,336,058

b) The distribution of income from operations, including restructuring and other items, by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	189,035	$	138,185	$	81,811
Rest of Europe		38,166		14,481		2,831
U.S.		45,320		39,058		29,472
Other		9,015		10,626		7,053
Total	$	281,536	$	202,350	$	121,167

c) The distribution of income from operations, excluding restructuring and other items, by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	189,035	$	138,185	$	82,867
Rest of Europe		38,166		23,277		6,269
U.S.		45,320		39,058		33,564
Other		9,015		10,626		7,500
Total	$	281,536	$	211,146	$	130,200

d) The distribution of property, plant and equipment, net, by geographical area was as follows:

	December 31,		December 31,
	2015		2014
	(in thousands)
Ireland	$	101,736	$	95,574
Rest of Europe		7,334		10,419
U.S.		34,520		33,978
Other		6,628		8,214
Total	$	150,218	$	148,185

e) The distribution of depreciation and amortization by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	22,100	$	20,731	$	19,826
Rest of Europe		11,055		7,478		6,595
U.S.		20,106		20,491		16,233
Other		4,416		3,842		3,860
Total	$	57,677	$	52,542	$	46,514

f) The distribution of total assets by geographical area was as follows:

	December 31,		December 31,
	2015		2014
	(in thousands)
Ireland	$	664,754	$	495,747
Rest of Europe		343,733		324,086
U.S.		641,769		648,559
Other		68,647		60,458
Total	$	1,718,903	$	1,528,850

g) The distribution of capital expenditures by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	30,900	$	15,117	$	3,976
Rest of Europe		1,916		2,278		1,887
U.S.		15,256		12,224		20,842
Other		1,658		3,160		2,783
Total	$	49,730	$	32,779	$	29,488

h) The following table sets forth the clients which represented 10% or more of the Company's net revenue in each of the periods set out below.

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013

Client A		31	%		31	%		26	%

Client B		-	*		-	*		10	%

* Net revenue did not exceed 10%.

i) The distribution of interest income by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	102	$	284	$	355
Rest of Europe		1,151		798		501
U.S.		4		-		-
Other		49		69		130
Total	$	1,306	$	1,151	$	986

j) The distribution of the income tax charge by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	21,795	$	18,384	$	11,073
Rest of Europe		8,007		2,855		(7	)
U.S.		3,580		4,860		5,072
Other		5,929		4,149		1,915
Total	$	39,311	$	30,248	$	18,053

- Definition

The entire disclosure for reporting segments including data and tables. Reportable segments include those that meet any of the following quantitative thresholds a) it's reported revenue, including sales to external customers and intersegment sales or transfers is 10 percent or more of the combined revenue, internal and external, of all operating segments b) the absolute amount of its reported profit or loss is 10 percent or more of the greater, in absolute amount of 1) the combined reported profit of all operating segments that did not report a loss or 2) the combined reported loss of all operating segments that did report a loss c) its assets are 10 percent or more of the combined assets of all operating segments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
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Reference 5: http://www.xbrl.org/2003/role/presentationRef
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Reference 6: http://www.xbrl.org/2003/role/presentationRef
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Name Accounting Standards Codification
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Reference 13: http://www.xbrl.org/2003/role/presentationRef
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Reference 14: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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+ Details

Supplemental Disclosure of Cash Flow Information

12 Months Ended

Dec. 31, 2015

Supplemental Disclosure of Cash Flow Information

18. Supplemental Disclosure of Cash Flow Information

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)

Non-cash interest on acquisition consideration payable*		-		-	$	240
Cash paid for interest	$	2,175	$	533	$	548
Cash paid for income taxes	$	14,829	$	17,829	$	14,103

* recorded within interest expense

Long-Term Debt - Senior Notes

12 Months Ended

Dec. 31, 2015

Long-Term Debt - Senior Notes

20. Long-Term Debt – Senior Notes

In December 2015 the Company issued $350 million in the private placement market.

In October 2015, the Company entered into an interest rate hedge in respect of the planned issuance of the Senior Notes in December 2015. The interest rate hedge matured in November 2015 when the interest rate on the Senior Notes was fixed. The interest rate hedge was effective in accordance with Financial Accounting Standards Board (“FASB”) ASC 815, “Derivatives and Hedging”. The cash proceeds ($4.6 million), representing the realized gain on the interest rate hedge were received on maturity in November 2015 and are recorded within Other Comprehensive Income. The realized gain will be amortized to the income statement, net against interest payable, over the period of the Senior Notes.

The Senior Notes agreement also includes certain financial covenants that require compliance with a consolidated leverage ratio, a minimum EBIT to consolidated net interest charge ratio and a maximum amount of priority debt, each of which are defined in the Note Purchase Agreement.

The Senior Notes have not been, and will not be, registered under the Securities Act of 1933, as amended, and may not be offered or sold in the United States absent registration or an applicable exemption from registration requirements.

Impact of New Accounting Pronouncements

12 Months Ended

Dec. 31, 2015

Impact of New Accounting Pronouncements

21. Impact of New Accounting Pronouncements

In January 2015, the FASB issued ASU 2015-01, which eliminates the concept of extraordinary items from U.S. GAAP as part of its simplification initiative. The ASU does not affect disclosure guidance for events or transactions that are unusual in nature or infrequent in their occurrence. The ASU is effective for fiscal years and, interim periods within those fiscal years, beginning after December 15, 2015. The ASU allows prospective or retrospective application. Early adoption is permitted if applied from the beginning of the fiscal year of adoption. The Company does not expect the adoption of ASU 2015-01 to have a material impact on the financial statements.

In February 2015, the FASB issued ASU 2015-02, which changes the way reporting enterprises evaluate whether (a) they should consolidate limited partnerships and similar entities, (b) fees paid to a decision maker or service provider are variable interests in a variable interest entity (VIE), and (c) variable interests in a VIE held by related parties of the reporting enterprise require the reporting enterprise to consolidate the VIE. It also eliminates the VIE consolidation model based on majority exposure to variability that applied to certain investment companies and similar entities. The new guidance excludes money market funds that are required to comply with Rule 2a-7 of the Investment Company Act of 1940 and similar entities from the U.S. GAAP consolidation requirements. The new consolidation guidance is effective for public business entities for annual and interim periods in fiscal years beginning after December 15, 2015. The Company does not expect the adoption of ASU 2015-02 to have a material impact on the financial statements.

In April 2015, the FASB issued ASU 2015-03, which intends to simplify the presentation of debt issuance costs. This ASU is effective for public business entities for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Subsequent to the issuance of ASU 2015-03, the SEC staff made an announcement regarding the presentation of debt issuance costs associated with line-of-credit arrangements, which was codified by the FASB in ASU 2015-15. The SEC staff guidance is effective upon adoption of ASU 2015-03. The Company does not expect the adoption of ASU 2015-03 to have a material impact on the financial statements.

In April 2015, the FASB issued ASU 2015-04, which permits an entity with a fiscal year-end that does not fall on a month-end to measure defined benefit plan obligations and assets as of the month-end that is closest to the entity’s fiscal year-end, and apply that methodology consistently from year to year. The ASU also requires an entity to adjust the measurement of defined benefit plan obligations and assets to reflect contributions or significant events that occur between the month-end date used to measure defined benefit plan obligations and assets and the entity’s fiscal year-end. This ASU is effective for public business entities for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The Company does not expect the adoption of ASU 2015-03 to have a material impact on the financial statements.

In April 2015, the FASB issued ASU 2015-05, which provides explicit guidance to help companies evaluate the accounting for fees paid by a customer in a cloud computing arrangement. The new guidance clarifies that if a cloud computing arrangement includes a software license, the customer should account for the license consistent with its accounting for other software licenses. If the arrangement does not include a software license, the customer should account for the arrangement as a service contract. This ASU is effective for public business entities for annual periods, including interim periods within those annual periods, beginning after December 15, 2015. The Company does not expect the adoption of ASU 2015-05 to have a material impact on the financial statements.

In April 2015, the FASB issued ASU 2015-06, which requires a master limited partnership (MLP) to allocate earnings (losses) of a transferred business entirely to the general partner when computing earnings per unit (EPU) for periods before the dropdown transaction occurred. The EPU that the limited partners previously reported would not change as a result of the dropdown transaction. The ASU also requires an MLP to disclose the effects of the dropdown transaction on EPU for the periods before and after the dropdown transaction occurred. The Company does not expect the adoption of ASU 2015-06 to have a material impact on the financial statements.

In July 2015, the FASB issued ASU 2015-11, which, for entities that do not measure inventory using the last-in, first-out (LIFO) or retail inventory method, changes the measurement principle for inventory from the lower of cost or market to lower of cost and net realizable value. The ASU also eliminates the requirement for these entities to consider replacement cost or net realizable value less an approximately normal profit margin when measuring inventory. This ASU is effective for public business entities in fiscal years beginning after December 15, 2017. The adoption of ASU 2015-11 is not expected to have a significant impact on the financial statements.

FASB ASU 2015-14 amends the effective dates of ASU 2014-09, Revenue from Contracts with Customers. The requirements are effective for annual periods and interim periods within fiscal years beginning after December 15, 2017. Earlier application is permitted only as of annual reporting periods beginning after December 15, 2016, including interim reporting periods within that reporting period. The adoption of ASU 2015-14 is not expected to have a significant impact on the financial statements.

In September 2015, the FASB issued ASU 2015-16, which eliminates the requirement for an acquirer to retrospectively adjust the financial statements for measurement-period adjustments that occur in periods after a business combination is consummated. The ASU is effective for public business entities for annual periods, including interim periods within those annual periods, beginning after December 15, 2015. The adoption of ASU 2015-14 is not expected to have a significant impact on the financial statements.

In November 2015, the FASB issued ASU 2015-17, which requires entities with a classified balance sheet to present all deferred tax assets and liabilities as noncurrent. The ASU 2015-17 has been early adopted in the financial statements presented. The impact is described in Note 13 to the financial statements.

In January 2016, the FASB issued ASU 2016-01, which will significantly change the income statement impact of equity investments, and the recognition of changes in fair value of financial liabilities when the fair value option is elected. The ASU is effective for public business entities for interim and annual periods in fiscal years beginning after December 15, 2017. The adoption of ASU 2016-01 is not expected to have a significant impact on the financial statements.

Related Parties

12 Months Ended

Dec. 31, 2015

Related Parties

22. Related Parties

On July 19, 2012, Mr. Peter Gray retired as a Director and employee of the Company. The Company subsequently entered into an agreement with Integritum Limited, a company controlled by Mr. Gray, for the provision of consultancy services for a period of two years from August 1, 2012, at an agreed fee of €265,000 ($350,000) per annum. This arrangement expired in August, 2014.

Subsidiaries of the Company earned revenue of $221,000 from GW Pharmaceuticals plc in the normal course of business. There were backlog awards at December 31, 2015 of $88,000. Tom Lynch, Chairman of the Company is a non-executive Director of GW Pharmaceuticals plc. The contract terms were agreed on an arm’s length basis.

Subsidiaries of the Company earned revenue of $100,000 (2014: $300,000) from Dignity Sciences Limited during the year. Dr. John Climax is a director and both Dr. John Climax and Dr. Ronan Lambe are shareholders of Dignity Sciences Limited. The contract terms were agreed on an arm’s length basis.

- Definition

The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.

+ References + Details

Significant Accounting Policies (Policies)

12 Months Ended

Dec. 31, 2015

Basis of Consolidation

(a) Basis of consolidation

Use of Estimates

(b) Use of estimates

Revenue Recognition

Reimbursable Expenses

(d) Reimbursable expenses

Direct Costs

(e) Direct costs

Direct costs consist of compensation, associated employee benefits and share-based payments for project-related employees and other direct project-related costs.

Advertising Costs

(f) Advertising costs

Foreign Currencies and Translation of Subsidiaries

(g) Foreign currencies and translation of subsidiaries

	Year ended December 31,
	(in thousands)
	2015			2014			2013
Amounts (credited)	$	(3,608	)	$	(5,942	)	$	(1,233	)

Disclosure About Fair Value of Financial Instruments

(h) Disclosure about fair value of financial instruments

The following methods and assumptions were used to estimate the fair value of each material class of financial instrument:

Business Combinations

(i) Business combinations

Goodwill and Impairment

(j) Goodwill and Impairment

Intangible Assets

(k) Intangible assets

Intangible assets are amortized on a straight line basis over their estimated useful life.

Cash and Cash Equivalents

(l) Cash and cash equivalents

Cash and cash equivalents include cash and highly liquid investments with initial maturities of three months or less and are stated at cost, which approximates market value.

Short Term Investments - Available for Sale

(m) Short term investments - available for sale

Inventory

(n) Inventory

Property, Plant and Equipment

(o) Property, plant and equipment

	Years
Building		40
Computer equipment and software		2-8
Office furniture and fixtures		8
Laboratory equipment		5
Motor vehicles		5

Leasehold improvements are amortized using the straight-line method over the estimated useful life of the asset or the lease term, whichever is shorter.

Leased Assets

(p) Leased assets

Costs in respect of operating leases are charged to the statement of operations on a straight line basis over the lease term.

Income Taxes

(q) Income taxes

Government Grants

(r) Government grants

Research and Development Credits

(s) Research and development credits

Pension Costs

(t) Pension costs

Net Income per Ordinary Share

(u) Net income per ordinary share

	Year Ended December 31,
	2015		2014		2013
Weighted average number of ordinary shares outstanding for basic net income per ordinary share		58,746,935		61,496,115		60,907,274
Effect of dilutive share options outstanding		1,543,098		1,635,302		1,345,977
Weighted average number of ordinary shares outstanding for diluted net income per ordinary share		60,290,033		63,131,417		62,253,251

Share-Based Compensation

(v) Share-based compensation

Impairment of Long-Lived Assets

(w) Impairment of long-lived assets

Derivative financial instruments

(x) Derivative financial instruments

Financing costs and gain on interest rate hedge

(y) Financing costs and gain on interest rate hedge

Reclassifications

(y) Reclassifications

Certain amounts in the consolidated financial statements have been reclassified where necessary to conform to the current year presentation.

Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2015

Adjustments Resulting From Foreign Currency Translations

Amounts credited or charged to the statement of operations for the years ended December 31, 2015, December 31, 2014 and December 31, 2013 were as follows:

	Year ended December 31,
	(in thousands)
	2015			2014			2013
Amounts (credited)	$	(3,608	)	$	(5,942	)	$	(1,233	)

Estimated Useful Lives of Assets

Depreciation of property, plant and equipment is computed using the straight line method based on the estimated useful lives of the assets as listed below:

	Years
Building		40
Computer equipment and software		2-8
Office furniture and fixtures		8
Laboratory equipment		5
Motor vehicles		5

Reconciliation of Number of Shares Used in Computation of Basic and Diluted Net Income Per Ordinary Share

The reconciliation of the number of shares used in the computation of basic and diluted net income per ordinary share is as follows:

	Year Ended December 31,
	2015		2014		2013
Weighted average number of ordinary shares outstanding for basic net income per ordinary share		58,746,935		61,496,115		60,907,274
Effect of dilutive share options outstanding		1,543,098		1,635,302		1,345,977
Weighted average number of ordinary shares outstanding for diluted net income per ordinary share		60,290,033		63,131,417		62,253,251

Goodwill (Tables)

12 Months Ended

Dec. 31, 2015

Goodwill

	December 31,			December 31,
	2015			2014
	(in thousands)
Opening goodwill	$	463,324		$	357,523
Current year acquisitions (note 4 (a) and (b))		133,123			121,209
Prior period acquisition (note 4(c))		4,418			-
Foreign exchange movement		(12,431	)		(15,408	)
Closing goodwill	$	588,434		$	463,324

PMG

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed

The table following summarizes the Company’s provisional estimates of the fair values of the assets acquired and liabilities assumed:

	December 4,
	2015
	(in thousands)
Cash	$	194
Property, plant and equipment		712
Goodwill*		41,039
Intangible asset**		10,259
Accounts receivable		12,997
Prepayments and other current assets		1,329
Accounts payable		(530	)
Other liabilities		(2,459	)
Net assets acquired		63,541

Cash consideration			53,681
Other liabilities assumed			9,860
Total cash outflows			63,541

Proforma Effect in Net Revenue Net Income and Earnings Per Share

	Year Ended
	December 31,
	2015		2014
	(in thousands)
Net revenue	$	1,601,891	$	1,527,685
Net income	$	243,004	$	172,390
Basic earnings per share	$	4.14	$	2.80
Diluted earnings per share	$	4.03	$	2.73

MediMedia Pharma Solutions

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed

The following table summarizes the Company’s provisional estimates of the fair values of the assets acquired and liabilities assumed:

	February 27,
	2015
	(in thousands)
Property, plant and equipment	$	1,049
Goodwill*		92,084
Customer lists		22,752
Order backlog		2,521
Accounts receivable		5,240
Unbilled Revenue		4,324
Prepayments and other current assets		621
Accounts payable		(749	)
Payments on account		(4,186	)
Deferred tax liability		(2,171	)
Other liabilities		(5,483	)
Net assets acquired	$	116,002


Cash consideration	$	108,717
Other liabilities assumed**		11,283
Gross cash outflows		120,000
Working capital adjustment		(3,998	)
Net cash outflows	$	116,002

**	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.

Proforma Effect in Net Revenue Net Income and Earnings Per Share

	Year Ended
	December 31,
	2015		2014
	(in thousands)
Net revenue	$	1,581,816	$	1,556,936
Net income	$	239,361	$	179,289
Basic earnings per share	$	4.07	$	2.92
Diluted earnings per share	$	3.97	$	2.84

Aptiv Solutions

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed

The following table summarizes the fair values of the assets acquired and the liabilities assumed:

	May 7,
	2014
	(in thousands)
Property, plant and equipment	$	6,924
Goodwill*		125,627
Customer relationships		21,400
Order backlog		7,900
Cash and cash equivalents		3,484
Accounts receivable		25,091
Unbilled revenue		21,154
Prepayments and other current assets		4,180
Non-current assets		2,911
Accounts payable		(9,565	)
Other liabilities		(29,782	)
Payments on account		(31,094	)
Non-current other liabilities		(11,303	)
Loan notes payable**		(17,790	)
Net assets acquired	$	119,137


Cash consideration			$143,500
Working capital adjustment			(1,964)
			141,536
Adjustments to cash consideration**			(22,399)
Net purchase consideration			$119,137

**Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.

Proforma Effect in Net Revenue Net Income and Earnings Per Share

	Year Ended
	December 31,
	2014		2013
	(in thousands)
Net revenue	$	1,543,820	$	1,451,682
Net income	$	172,508	$	101,857
Basic earnings per share	$	2.81	$	1.67
Diluted earnings per share	$	2.73	$	1.64

Clinical Trial Services of Cross Country Healthcare Inc.

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed

The following table summarizes the estimated fair values of the assets acquired and the liabilities assumed:

	February 15,
	2013
	(in thousands)
Property, plant and equipment	$	339
Goodwill*		36,922
Intangible asset – customer relationships		3,300
Intangible asset – order backlog		600
Cash and cash equivalents		1,039
Accounts receivable		9,200
Unbilled revenue		2,128
Prepayments and other current assets		465
Non-current assets		6
Other liabilities		(2,285	)
Non-current other liabilities		(16	)
Net assets acquired	$	51,698


Cash consideration	$	51,897
Working capital adjustment		(199	)
Net purchase consideration	$	51,698

Proforma Effect in Net Revenue Net Income and Earnings Per Share

	Year Ended
	December 31,
	2013		2012
	(in thousands)
Net revenue	$	1,343,996	$	1,182,734
Net income	$	103,133	$	58,944
Basic earnings per share	$	1.69	$	0.98
Diluted earnings per share	$	1.66	$	0.98

Intangible Assets (Tables)

12 Months Ended

Dec. 31, 2015

Intangible Assets

	December 31,			December 31,
	2015			2014
Cost	(in thousands)
Customer relationships acquired	$	90,541		$	36,130
Technology asset acquired		11,169			11,169
Order backlog		13,592			3,171
Tradenames acquired		1,357			1,357
Volunteer list acquired		1,325			1,325
Non-compete arrangements		489			489
Aptiv intangible asset		-			30,037
Foreign exchange movement		(5,092	)		(2,769	)
Total cost		113,381			80,909
Accumulated amortization		(49,587	)		(32,120	)
Foreign exchange movement		2,333			930
Net book value	$	66,127		$	49,719

Future Intangible Asset Amortization Expense

Future intangible asset amortization expense for the years ended December 31, 2016 to December 31, 2020 is as follows:

	Year ended December 31, (in thousands)
2016	$	15,599
2017		12,451
2018		11,034
2019		9,494
2020		9,215
	$	57,793

Property, Plant and Equipment, net (Tables)

12 Months Ended

Dec. 31, 2015

Property Plant and Equipment Net

	December 31,			December 31,
	2015			2014
	(in thousands)
Cost
Land	$	3,464		$	3,464
Building		80,861			88,580
Computer equipment and software		282,909			247,980
Office furniture and fixtures		65,152			64,690
Laboratory equipment		31,098			23,599
Leasehold improvements		20,647			19,516
Motor vehicles		47			47
		484,178			447,876
Less accumulated depreciation and asset write offs		(333,960	)		(299,691	)

Property, plant and equipment (net)	$	150,218		$	148,185

Employee Benefits (Tables) - Foreign Postretirement Benefit Plan

12 Months Ended

Dec. 31, 2015

UNITED KINGDOM

Pension Costs of Plan

The pension costs of this plan are presented in the following tables in accordance with the requirements of ASC 715-60, Defined Benefit Plans – Other Postretirement. The plan has been closed to new entrants with effect from July 1, 2003.

Change in benefit obligation	December 31, 2015			December 31, 2014
	(in thousands)
Benefit obligation at beginning of year	$	32,875		$	24,958
Service cost		78			91
Interest cost		1,140			1,235
Plan participants’ contributions		26			44
Plan curtailments		-			359
Benefits paid		(1,111	)		(68	)
Actuarial (gain)/loss		(3,992	)		8,270
Foreign currency exchange rate changes		(1,647	)		(2,014	)
Benefit obligation at end of year	$	27,369		$	32,875

Change in plan assets	December 31, 2015			December 31, 2014
	(in thousands)
Fair value of plan assets at beginning of year	$	25,409		$	21,422
Actual return on plan assets		277			5,424
Employer contributions		114			155
Plan participants’ contributions		26			44
Benefits paid		(1,111	)		(68	)
Foreign currency exchange rate changes		(1,348	)		(1,568	)
Fair value of plan assets at end of year	$	23,367		$	25,409

Funded Status

Funded status	December 31, 2015			December 31, 2014
	(in thousands)
Projected benefit obligation	$	(27,369	)	$	(32,875	)
Fair value of plan assets		23,367			25,409
Funded status	$	(4,002	)	$	(7,466	)

Non-current other liabilities (note 8)	$	(4,002	)	$	(7,466	)

Components of Net Periodic Benefit Cost

The following amounts were recorded in the consolidated statement of operations as components of the net periodic benefit cost:

	December 31, 2015			December 31, 2014			December 31, 2013
	(in thousands)
Service cost	$	78		$	91		$	251
Interest cost		1,140			1,235			1,005
Expected return on plan assets		(661	)		(1,299	)		(983	)
Amortization of net loss		224			20			130
Curtailment loss		-			359			-
Net periodic benefit cost	$	781		$	406		$	403

Assumptions Used in Calculating Net Periodic Benefit Cost


	December 31,			December 31,			December 31,
	2015			2014			2013
Discount rate		3.6	%		4.7	%		4.6	%
Rate of compensation increase		3.6	%		4.0	%		3.4	%
Expected rate of return on plan assets		2.7	%		6.1	%		5.7	%

Accumulated other comprehensive income	December 31, 2015				December 31, 2014		December 31, 2013
	(in thousands)
Actuarial (gain)/loss - benefit obligation	$	(3,992	)	$	8,270			$	680
Actuarial loss/(gain) – plan assets		384			(4,125	)			(1,933	)
Actuarial gain recognized in net periodic benefit cost		(224	)		(20	)			(130	)
Total	$	(3,832	)	$	4,125			$	(1,383	)

Amounts Recognized in Accumulated Other Comprehensive Income Which Have Not Yet Been Recognized as Components of Net Periodic Benefit Cost

Amounts recognized in accumulated other comprehensive income that have not yet been recognized as components of net periodic benefit cost are as follows:

		December 31, 2015		December 31, 2014		December 31, 2013
		(in thousands)
Net actuarial loss	$	2,281	$	6,113	$	1,988
Total	$	2,281	$	6,113	$	1,988

Assumptions Used in Calculating Pension Benefit Obligations

The following assumptions were used in determining the benefit obligation at December 31, 2015:

	December 31,			December 31,
	2015			2014
Discount rate		4.0	%		3.6	%
Rate of compensation increase		3.7	%		3.6	%

Actual Plan Asset Allocations

The expected long term rates of return on different asset classes are as follows:

Asset Category	Expected long-term return per annum
Corporate Bonds		4.0	%
Gilts		2.6	%

Actual Plan Asset Allocations

The underlying asset split of the fund is shown below.

Asset Category	December 31, 2015			December 31, 2014
Corporate Bonds		26	%		26	%
Gilts		74	%		74	%
		100	%		100	%

Annual Benefit Payments which Reflect Expected Future Service

The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid.

	(in thousands)

2016		66
2017		68
2018		71
2019		72
2020		75
Years 2021 - 2025	$	376

UNITED KINGDOM | Fair Value, Inputs, Level 1

Plan Asset Fair Value Measurements

	Quoted Prices in Active Markets for Identical Assets Level 1 (in thousands)
	December 31, 2015		December 31, 2014
Cash	$	3	$	16

Fixed Income Securities
Legal and General Active Corporate Bond – Over 10 Year		6,256		6,560
Legal and General Gilt Funds		6,528		6,977
Legal and General Index Linked Gilt Funds		10,580		11,856
	$	23,367	$	25,409

SWITZERLAND

Pension Costs of Plan

The pension costs of this plan are presented in the following tables in accordance with the requirements of ASC 715-60, Defined Benefit Plans – Other Postretirement.

Change in benefit obligation	December 31, 2015
	(in thousands)

Benefit obligation at beginning of year		8,884
Service cost		618
Interest cost		159
Actuarial loss		81
Foreign currency exchange rate changes		(1,205	)
Benefit obligation at end of year		8,537

Change in plan assets

Fair value of plan assets at beginning of year	7,061
Expected return on plan assets	93
Actual return on plan assets	(1,075	)
Scheme contributions	194
Plan participants’ contributions	216
Benefits paid	(1,146	)
Foreign currency exchange rate changes	7
Fair value of plan assets at end of year	5,350

Funded Status

Funded status	December 31, 2015
	(in thousands)
Projected benefit obligation	$	8,537
Fair value of plan assets		(5,350	)
Funded status		3,187

Non-current other liabilities (note 8)		3,187

Components of Net Periodic Benefit Cost

	December 31, 2015
	(in thousands)
Service cost	$	402
Interest cost		159
Expected return on plan assets		(119	)
Settlement loss		18
Net periodic benefit cost	$	460

Assumptions Used in Calculating Net Periodic Benefit Cost

The following assumptions were used at the commencement of the year in determining the net periodic pension benefit cost for the year ended December 31, 2015:

	December 31,
	2015
Discount rate		1.35	%
Rate of compensation increase		2.0	%
Expected rate of return on plan assets		1.35	%

Accumulated other comprehensive income	December 31, 2015
Actuarial loss - benefit obligation	$	81
Actuarial (gain) – plan assets		1,075
Prior service cost recognized in net periodic benefit cost		(17	)
Total	$	1,139

Assumptions Used in Calculating Pension Benefit Obligations

The following assumptions were used in determining the benefit obligation at December 31, 2015:

	December 31,
	2015
Discount rate		0.95	%
Rate of compensation increase		2.0	%

Actual Plan Asset Allocations

The expected long term rates of return on different asset classes are as follows:

Asset Category	December 31, 2015
Equity securities		1	%
Debt securities		75	%
Real estate		12	%
Other		12	%
		100	%

Actual Plan Asset Allocations

The following annual benefit payments, which reflect expected future service as appropriate, are expected to be paid.

	(in thousands)

2016		166
2017		169
2018		171
2019		182
2020		182
Years 2021 - 2025	$	1,205

Equity Incentive Schemes and Stock Compensation Charges (Tables)

12 Months Ended

Dec. 31, 2015

Transactions for Company's Share Option Plans

The following table summarizes the transactions for the Company’s share option plans for the years ended December 31, 2015, December 31, 2014 and December 31, 2013:

	Options Granted Under Plans			Number of Shares			Weighted Average Exercise Price		Weighted Average Grant Date Fair Value
Outstanding at December 31, 2012		4,350,631			4,350,631		$	23.01	$	9.17
Granted		264,950			264,950		$	33.09	$	12.05
Exercised		(1,249,759	)		(1,249,759	)	$	21.60	$	8.58
Cancelled		(392,034	)		(392,034	)	$	25.27	$	10.02
Outstanding at December 31, 2013		2,973,788			2,973,788		$	24.20	$	9.57
Granted		366,985			366,985		$	45.82	$	14.09
Exercised		(926,407	)		(926,407	)	$	24.02	$	9.45
Cancelled		(186,666	)		(186,666	)	$	22.17	$	9.01
Outstanding at December 31, 2014		2,227,700			2,227,700		$	28.00	$	10.40
Granted		259,059			259,059		$	68.25	$	19.75
Exercised		(773,753	)		(773,753	)	$	27.13	$	10.31
Cancelled		(86,424	)		(86,424	)	$	27.32	$	10.31
Outstanding at December 31, 2015		1,626,582			1,626,582		$	34.87	$	11.94
Vested and exercisable at December 31, 2015		657,729			657,729		$	24.15	$	9.36

Non Vested Shares Outstanding

Non-vested shares outstanding as at December 31, 2015 are as follows:

	Options Outstanding Number of Shares			Weighted Average Exercise Price		Weighted Average Fair Value

Non-vested outstanding at December 31, 2014		1,203,150		$	30.54	$	10.98

Granted		259,059			68.25		19.75
Vested		(379,992	)		28.25		10.49
Forfeited		(113,364	)		25.21		9.50

Non-vested outstanding at December 31, 2015		968,853		$	42.14	$	13.69

Information Concerning Outstanding and Exercisable Share Options

The following table summarizes information concerning outstanding and exercisable share options as of December 31, 2015:

Options Outstanding								Options Exercisable
Range Exercise Price		Number of Shares		Weighted Average Remaining Contractual Life		Weighted Average Exercise Price		Number of Shares		Weighted Average Exercise Price
$	15.84		50,000		1.33	$	15.84		50,000	$	15.84
$	16.80		60,000		3.83	$	16.80		30,000	$	16.80
$	17.17		12,000		3.85	$	17.17		6,000	$	17.17
$	18.98		600		0.87	$	18.98		600	$	18.98
$	20.16		400		2.88	$	20.16		400	$	20.16
$	20.28		255,694		3.17	$	20.28		158,073	$	20.28
$	20.59		57,200		4.14	$	20.59		4,000	$	20.59
$	22.26		61,755		1.15	$	22.26		61,755	$	22.26
$	22.30		250,939		4.32	$	22.30		109,894	$	22.30
$	23.66		7,890		4.58	$	23.66		4,450	$	23.66
$	24.46		101,412		2.18	$	24.46		101,412	$	24.46
$	26.20		1,950		2.39	$	26.20		1,950	$	26.20
$	26.71		4,450		4.86	$	26.71		2,670	$	26.71
$	29.45		3,000		2.33	$	29.45		3,000	$	29.45
$	32.37		179,603		5.34	$	32.37		70,997	$	32.37
$	35.33		1,350		0.16	$	35.33		1,350	$	35.33
$	36.22		27,213		5.47	$	36.22		7,908	$	36.22
$	37.90		7,100		5.93	$	37.90		920	$	37.90
$	40.83		105,992		6.40	$	40.83		20,468	$	40.83
$	47.03		71,670		6.18	$	47.03		7,520	$	47.03
$	48.67		140,881		6.21	$	48.67		13,556	$	48.67
$	51.35		4,030		6.61	$	51.35		806	$	51.35
$	66.47		15,969		7.39	$	66.47		-	$	66.47
$	66.97		3,118		7.46	$	66.97		-	$	66.97
$	68.39		232,366		7.22	$	68.39		-	$	68.39

$	15.84 - $68.39		1,626,582		4.76	$	34.87		657,729	$	24.15

Weighted Average Fair Values and Assumptions Used

The weighted average fair values and assumptions were as follows:

	Year Ended
	December 31,			December 31,			December 31,
	2015			2014			2013

Weighted average fair value	$	19.75		$	14.09		$	12.05

Assumptions:
Expected volatility		30	%		32	%		40	%
Dividend yield		0	%		0	%		0	%
Risk-free interest rate		1.58	%		1.57	%		0.76	%
Expected life	5.0 years			5.0 years			5.0 years

RSU and PSU Activity

The following table summarizes RSU and PSU activity for the year ended December 31, 2015:

	PSU Outstanding Number of Shares			PSU Weighted Average Fair Value		PSU Weighted Average Remaining Contractual Life		RSU Outstanding Number of Shares			RSU Weighted Average Fair Value		RSU Weighted Average Remaining Contractual Life


Outstanding at December 31, 2014		669,171		$	39.78		1.77		1,038,996		$	35.19		1.67

Granted		259,110		$	68.82				389,542		$	67.02
Shares vested		(7,990	)		32.38				(268,870	)	$	26.06
Forfeited		(18,518	)	$	46.82				(92,055	)	$	44.43

Outstanding at December 31, 2015		901,773		$	72.55		2.49		1,067,613		$	48.30		1.48

Schedule of Non-cash Stock Compensation Expense

Non-cash stock compensation expense for the year ended December 31, 2015 has been allocated as follows:

	Year ended
	December 31, 2015		December 31, 2014		December 31, 2013
	(in thousands)
Direct costs	$	18,358	$	12,531	$	7,835
Selling, general and administrative	$	14,959	$	10,211	$	6,385
Total compensation costs	$	33,317	$	22,742	$	14,220

Income Taxes (Tables)

12 Months Ended

Dec. 31, 2015

Components of Income Before Provision for Income Taxes

The components of income before provision for income taxes are as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	184,643	$	143,889	$	80,914
United States		15,436		6,966		16,218
Other		78,771		51,861		23,733
Income before provision for income taxes	$	278,850	$	202,716	$	120,865

Components of Provision for Income Taxes

The components of provision for income taxes are as follows:

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Provision for income taxes:
Current tax expense:
Ireland	$	21,769		$	19,562		$	9,158
United States		684			7,891			14,492
Other		13,701			10,695			4,876
Total current tax expense		36,154			38,148			28,526

Deferred tax expense/(benefit):
Ireland		26			(1,178	)		1,914
United States		2,896			(3,031	)		(9,420	)
Other		235			(3,691	)		(2,967	)
Total deferred tax expense/(benefit)		3,157			(7,900	)		(10,473	)

Provision for income taxes		39,311			30,248			18,053

Impact on shareholders equity and other comprehensive income of the tax consequence of :
Excess tax benefit on stock compensation		(1,905	)		(2,404	)		(1,651	)
Currency impact on long term funding		3,574			178			87

Total	$	40,980		$	28,022		$	16,489

Reconciliation of Consolidated Reported Provision for Income Taxes and Statutory Rate

The Company’s consolidated reported provision for income taxes differed from the amount that would result from applying the Irish statutory rate as set forth below:

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Taxes at Irish statutory rate of 12.5% (2014:12.5%; 2013:12.5%)	$	34,856		$	25,340		$	15,108
Foreign and other income taxed at higher rates		4,614			3,152			4,873
Research & development tax incentives		(695	)		(1,810	)		(2,598	)
Movement in valuation allowance		(4,133	)		(1,965	)		2,389
Effects of change in tax rates		(16	)		543			1,553
Increase/(decrease) in unrecognized tax benefits		5,085			2,869			(1,409	)
Effects of permanent items		(463	)		2,048			(1,790	)
Other		63			71			(73	)
Provision for income taxes	$	39,311		$	30,248		$	18,053

Tax Effects of Temporary Differences that Give Rise to Significant Portions of Deferred Tax Assets and Deferred Tax Liabilities

The tax effects of temporary differences that give rise to significant portions of deferred tax assets and deferred tax liabilities are presented below:

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Deferred tax liabilities:
Property, plant and equipment	$	2,665		$	4,270		$	6,501
Goodwill		21,571			18,645			14,013
Other intangible assets		7,369			3,657			970
Other		1,293			1,947			1,111
Total deferred tax liabilities recognized		32,898			28,519			22,595

Deferred tax assets:
Operating loss and tax credits carryforwards		22,186			30,586			29,696
Property, plant and equipment		4,818			4,002			2,739
Accrued expenses and payments on account		29,473			37,620			30,136
Stock compensation		12,959			8,717			6,291
Deferred compensation expense		2,174			1,853			1,187
Other		566			1,244			92
Total deferred tax assets		72,176			84,022			70,141
Valuation allowance for deferred tax assets		(17,184	)		(23,145	)		(24,348	)
Deferred tax assets recognized		54,992			60,877			45,793
Overall net deferred tax asset	$	22,094		$	32,358		$	23,198

Expected Expiry Dates of NOL's

The expected expiry dates of these losses are as follows:

	Federal NOL’s		State NOL’s
	(in thousands)

2016-2017		565		-
2023-2033		34,800		63,793
2035		16,252		25,987

	$	51,617	$	89,780

Reconciliation of Beginning and Ending Amount of Total Unrecognized Tax Benefits

A reconciliation of the beginning and ending amount of total unrecognized tax benefits is as follows:

	December 31,			December 31,			December 31,
	2015			2014			2013
	(in thousands)
Unrecognized tax benefits at start of year	$	23,201		$	5,780		$	7,189


Increase related to acquired tax positions		778			14,552			-
Increase related to prior year tax positions		1,482			565			-
Decrease related to prior year tax positions		-			(183	)		(494	)
Increase related to current year tax positions		3,063			3,709			2,269
Settlements		(315	)		(2	)		(899	)
Lapse of statute of limitations		(43	)		(1,220	)		(2,285	)
Unrecognized tax benefits at end of year	$	28,166		$	23,201		$	5,780

Restructuring and other items (Tables)

12 Months Ended

Dec. 31, 2015

Recognized Restructuring and Other Items, Net

Restructuring and other items recognized during the year ended December 31, 2015 comprise:

	Year Ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Restructuring charges		-	$	8,796	$	9,033
Net charge		-	$	8,796	$	9,033

Restructuring Charges

	Onerous			Asset
	Lease			Impairment			Total
	(in thousands)

Total provision recognized	$	3,167		$	5,629		$	8,796
Asset write-off		-			(5,629	)		(5,629	)
Provision at December 31, 2014	$	3,167			-		$	3,167
Utilized		(1,167	)		-			(1,167	)
Provision at December 31, 2015		2,000			-			2,000

Details of Movement in Restructuring Provisions Recognized

Details of the movement in this restructuring plan are as follows:

	Workforce			Office
	Reductions			Consolidations			Total
	(in thousands)

Q1 Plan - Initial provision recognized	$	3,903		$	509		$	4,412
Q2 Plan - Initial provision recognized		4,228			393			4,621
Total provision recognized		8,131			902			9,033
Cash payments		(6,544	)		(199	)		(6,743	)
Amounts released		(93	)		-			(93	)
Foreign exchange movement		(3	)		-			(3	)
Provision at December 31, 2013	$	1,491		$	703		$	2,194
Cash payments		(1,319	)		(337	)		(1,656	)
Amounts released		-			-			-
Foreign exchange movement		(1	)		-			(1	)
Provision at December 31, 2014	$	171		$	366		$	537
Cash payments		(82	)		-			(82	)
Amounts released		-			(339	)		(339	)
Provision at December 31, 2015	$	89		$	27		$	116

Business Segment and Geographical Information (Tables)

12 Months Ended

Dec. 31, 2015

Distribution of Net Revenue by Geographical Area

a) The distribution of net revenue by geographical area was as follows:

		Year ended
		December 31, 2015		December 31, 2014		December 31, 2013
		(in thousands)
Ireland	$	429,631	$	360,376	$	272,683
Rest of Europe		330,487		372,634		333,543
U.S.		650,941		605,815		582,250
Other		163,919		164,491		147,582
Total	$	1,574,978	$	1,503,316	$	1,336,058

Distribution of Income from Operations by Geographical Area

b) The distribution of income from operations, including restructuring and other items, by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	189,035	$	138,185	$	81,811
Rest of Europe		38,166		14,481		2,831
U.S.		45,320		39,058		29,472
Other		9,015		10,626		7,053
Total	$	281,536	$	202,350	$	121,167

c) The distribution of income from operations, excluding restructuring and other items, by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	189,035	$	138,185	$	82,867
Rest of Europe		38,166		23,277		6,269
U.S.		45,320		39,058		33,564
Other		9,015		10,626		7,500
Total	$	281,536	$	211,146	$	130,200

Distribution of Property, Plant and Equipment, Net, by Geographical Area

d) The distribution of property, plant and equipment, net, by geographical area was as follows:

	December 31,		December 31,
	2015		2014
	(in thousands)
Ireland	$	101,736	$	95,574
Rest of Europe		7,334		10,419
U.S.		34,520		33,978
Other		6,628		8,214
Total	$	150,218	$	148,185

Distribution of Depreciation and Amortization by Geographical Area

e) The distribution of depreciation and amortization by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	22,100	$	20,731	$	19,826
Rest of Europe		11,055		7,478		6,595
U.S.		20,106		20,491		16,233
Other		4,416		3,842		3,860
Total	$	57,677	$	52,542	$	46,514

Distribution of Total Assets by Geographical Area

f) The distribution of total assets by geographical area was as follows:

	December 31,		December 31,
	2015		2014
	(in thousands)
Ireland	$	664,754	$	495,747
Rest of Europe		343,733		324,086
U.S.		641,769		648,559
Other		68,647		60,458
Total	$	1,718,903	$	1,528,850

Distribution of Capital Expenditures by Geographical Area

g) The distribution of capital expenditures by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	30,900	$	15,117	$	3,976
Rest of Europe		1,916		2,278		1,887
U.S.		15,256		12,224		20,842
Other		1,658		3,160		2,783
Total	$	49,730	$	32,779	$	29,488

Clients Representing Company's Net Revenue

h) The following table sets forth the clients which represented 10% or more of the Company's net revenue in each of the periods set out below.

	Year ended
	December 31,			December 31,			December 31,
	2015			2014			2013

Client A		31	%		31	%		26	%

Client B		-	*		-	*		10	%

* Net revenue did not exceed 10%.

Distribution of Interest Income by Business Segment

i) The distribution of interest income by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	102	$	284	$	355
Rest of Europe		1,151		798		501
U.S.		4		-		-
Other		49		69		130
Total	$	1,306	$	1,151	$	986

Distribution of Tax Charge by Geographical Area

j) The distribution of the income tax charge by geographical area was as follows:

	Year ended
	December 31,		December 31,		December 31,
	2015		2014		2013
	(in thousands)
Ireland	$	21,795	$	18,384	$	11,073
Rest of Europe		8,007		2,855		(7	)
U.S.		3,580		4,860		5,072
Other		5,929		4,149		1,915
Total	$	39,311	$	30,248	$	18,053

Description of Business - Additional Information (Detail)	12 Months Ended
	Dec. 31, 2015 Employee Country Location
Product Information [Line Items]
Number of employees \| Employee	11,900
Number of locations in which company operates \| Location	90
Number of countries in which company operates \| Country	37
Geographic Concentration Risk \| United States \| Sales Revenue, Net
Product Information [Line Items]
Percentage of company revenue	41.30%
Geographic Concentration Risk \| Europe \| Sales Revenue, Net
Product Information [Line Items]
Percentage of company revenue	48.30%
Geographic Concentration Risk \| Rest of World \| Sales Revenue, Net
Product Information [Line Items]
Percentage of company revenue	10.40%

Significant Accounting Policies - Additional Information (Detail) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Significant Accounting Policies [Line Items]
Advertising and promotion expense	$ 4,513,750	$ 3,563,900	$ 5,195,120
Impairment charge	0	0	$ 0
Carrying value of inventory	1,800,000	$ 1,700,000
Cash proceeds from interest rate hedge	$ 4,658,000
Interest rate hedge, inception date	Oct. 05, 2015
Interest rate hedge, maturity date	Nov. 17, 2015
Senior Notes
Significant Accounting Policies [Line Items]
Debt instrument, interest rate	3.64%
Debt instrument, term	5 years

Adjustments Resulting from Foreign Currency Translation (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Intercompany Foreign Currency Balance [Line Items]
Amounts (credited)	$ (3,608)	$ (5,942)	$ (1,233)

Estimated Useful Lives of Assets (Detail)	12 Months Ended
Estimated Useful Lives of Assets (Detail)	Dec. 31, 2015
Building
Property, Plant and Equipment [Line Items]
Estimated useful lives	40 years
Office furniture and fixtures
Property, Plant and Equipment [Line Items]
Estimated useful lives	8 years
Laboratory equipment
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Motor vehicles
Property, Plant and Equipment [Line Items]
Estimated useful lives	5 years
Computer equipment and software \| Minimum
Property, Plant and Equipment [Line Items]
Estimated useful lives	2 years
Computer equipment and software \| Maximum
Property, Plant and Equipment [Line Items]
Estimated useful lives	8 years

Reconciliation of Number of Shares Used in Computation of Basic and Diluted Net Income Per Ordinary Share (Detail) - shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Weighted Average Number of Diluted Shares Outstanding [Line Items]
Weighted average number of ordinary shares outstanding for basic net income per ordinary share	58,746,935	61,496,115	60,907,274
Effect of dilutive share options outstanding	1,543,098	1,635,302	1,345,977
Weighted average number of ordinary shares outstanding for diluted net income per ordinary share	60,290,033	63,131,417	62,253,251

Cost and Fair Value of Investments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
At start of year	$ 97,100	$ 138,317
Additions	14,194	61,328
Disposals	(25,250)	(102,565)
Unrealized capital (loss)/gain - investments	(54)	20
At end of year	$ 85,990	$ 97,100

Goodwill (Detail) - USD ($) $ in Thousands	12 Months Ended
Goodwill (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Goodwill [Line Items]
Opening goodwill	$ 463,324	$ 357,523
Current year acquisitions (note 4 (a) and (b))	133,123	121,209
Prior period acquisition (note 4(c))	4,418
Foreign exchange movement	(12,431)	(15,408)
Closing goodwill	$ 588,434	$ 463,324

Goodwill - Additional Information (Detail)
$ in Thousands

1 Months Ended

Dec. 04, 2015

USD ($)

Patient

Site

Mar. 25, 2015

USD ($)

Feb. 27, 2015

USD ($)

May. 07, 2014

USD ($)

Feb. 15, 2013

USD ($)

Oct. 31, 2013

USD ($)

Dec. 31, 2015

USD ($)

Dec. 31, 2014

USD ($)

Dec. 31, 2013

USD ($)

Business Acquisition [Line Items]

Goodwill

$ 588,434

$ 463,324

$ 357,523

Clinical Trial Services of Cross Country Healthcare Inc.

Business Acquisition [Line Items]

Goodwill

^[1]

$ 36,922

Cash consideration

51,897

Working capital adjustment

$ 199

PMG

Business Acquisition [Line Items]

Goodwill

$ 41,039

^[2]

41,039

Cash consideration

53,681

Other liabilities assumed

$ 9,860

Number of clinical research sites acquired | Site

Working capital targets achievement period

90 days

PMG | Minimum

Business Acquisition [Line Items]

Number of active patients via electronic medical records acquired | Patient

2,000,000

MediMedia Pharma Solutions

Business Acquisition [Line Items]

Goodwill

$ 92,084

^[3]

$ 92,084

Cash consideration

108,717

Other liabilities assumed

^[4]

11,283

Cash consideration, net of working capital adjustment

104,800

Working capital adjustment

$ 3,998

Aptiv Solutions

Business Acquisition [Line Items]

Goodwill

^[5]

$ 125,627

Cash consideration

143,500

Working capital adjustment

$ 1,964

Percentage of common stock acquired

100.00%

Adjustments to cash consideration

^[6]

$ 22,399

[1]	Goodwill represents the acquisition of an established workforce with experience in the clinical research industry, thereby allowing the Company to enhance its capabilities in global resourcing and FSP and also medical and safety services. Goodwill related to the US portion of the business acquired is tax deductible.
[2]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development.
[3]	Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry.
[4]	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.
[5]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. Goodwill related to the US portion of the business acquired is tax deductible.
[6]	Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of PMG (Detail) - USD ($)
$ in Thousands

Dec. 04, 2015

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Business Acquisition [Line Items]

Goodwill

$ 588,434

$ 463,324

$ 357,523

PMG

Business Acquisition [Line Items]

Cash

$ 194

Property, plant and equipment

712

Goodwill

41,039

^[1]

$ 41,039

Intangible asset

^[2]

10,259

Accounts receivable

12,997

Prepayments and other current assets

1,329

(530)

(2,459)

63,541

53,681

Other liabilities assumed

9,860

Total cash outflows

$ 63,541

[1]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development.
[2]	The Company has estimated a separate intangible asset (in respect of customer lists acquired) of $10.3 million. This assessment is under review and will be finalized within 12 months of the date of acquisition.

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of PMG (Parenthetical) (Detail) - PMG
$ in Thousands

Dec. 04, 2015

USD ($)

Business Acquisition [Line Items]

Intangible asset

$ 10,259

^[1]

Customer Lists

Business Acquisition [Line Items]

Intangible asset

$ 10,300

[1]	The Company has estimated a separate intangible asset (in respect of customer lists acquired) of $10.3 million. This assessment is under review and will be finalized within 12 months of the date of acquisition.

Proforma Effect in Net Revenue, Net Income and Earnings Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
PMG
Business Acquisition [Line Items]
Net revenue	$ 1,601,891	$ 1,527,685
Net income	$ 243,004	$ 172,390
Basic earnings per share	$ 4.14	$ 2.80
Diluted earnings per share	$ 4.03	$ 2.73
Clinical Trial Services of Cross Country Healthcare Inc.
Business Acquisition [Line Items]
Net revenue			$ 1,343,996	$ 1,182,734
Net income			$ 103,133	$ 58,944
Basic earnings per share			$ 1.69	$ 0.98
Diluted earnings per share			$ 1.66	$ 0.98
MediMedia Pharma Solutions
Business Acquisition [Line Items]
Net revenue	$ 1,581,816	$ 1,556,936
Net income	$ 239,361	$ 179,289
Basic earnings per share	$ 4.07	$ 2.92
Diluted earnings per share	$ 3.97	$ 2.84
Aptiv Solutions
Business Acquisition [Line Items]
Net revenue		$ 1,543,820	$ 1,451,682
Net income		$ 172,508	$ 101,857
Basic earnings per share		$ 2.81	$ 1.67
Diluted earnings per share		$ 2.73	$ 1.64

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of MediMedia Pharma Solutions (Detail) - USD ($)
$ in Thousands

Feb. 27, 2015

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Business Acquisition [Line Items]

Goodwill

$ 588,434

$ 463,324

$ 357,523

MediMedia Pharma Solutions

Business Acquisition [Line Items]

Property, plant and equipment

$ 1,049

Goodwill

92,084

^[1]

$ 92,084

Accounts receivable

5,240

Unbilled revenue

4,324

Prepayments and other current assets

621

Accounts payable

(749)

Payments on account

(4,186)

Deferred tax liability

(2,171)

Other liabilities

(5,483)

Net assets acquired

116,002

Cash consideration

108,717

Other liabilities assumed

^[2]

11,283

Gross cash outflows

120,000

Working capital adjustment

(3,998)

Net cash outflows

116,002

MediMedia Pharma Solutions | Customer Lists

Business Acquisition [Line Items]

Intangible asset

22,752

MediMedia Pharma Solutions | Order Backlog

Business Acquisition [Line Items]

Intangible asset

$ 2,521

[1]	Goodwill represents the acquisition of an established workforce with experience in the provision of strategic payer-validated market access solutions while the acquisition of Complete Healthcare Communications comprises an established workforce with significant communication experience working with medical affairs, commercial and brand development teams within the life science industry.
[2]	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of MediMedia Pharma Solutions (Parenthetical) (Detail)
$ in Thousands

Feb. 27, 2015

USD ($)

MediMedia Pharma Solutions

Business Acquisition [Line Items]

Other liabilities assumed

$ 11,283

^[1]

[1]	Payments made at acquisition date of $11.3 million were in respect of certain one-time liabilities at the acquisition date which have subsequently been discharged.

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of Aptiv Solutions (Detail) - USD ($)
$ in Thousands

Mar. 25, 2015

May. 07, 2014

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Business Acquisition [Line Items]

Goodwill

$ 588,434

$ 463,324

$ 357,523

Aptiv Solutions

Business Acquisition [Line Items]

Property, plant and equipment

$ 6,924

Goodwill

^[1]

125,627

Cash and cash equivalents

3,484

Accounts receivable

25,091

Unbilled revenue

21,154

Prepayments and other current assets

4,180

2,911

(9,565)

(29,782)

(31,094)

Non-current other liabilities

(11,303)

Loan notes payable

(17,790)

Net assets acquired

119,137

Cash consideration

143,500

Working capital adjustment

$ (1,964)

(1,964)

Gross cash outflows

141,536

Adjustments to cash consideration

^[2]

(22,399)

Net assets acquired/Net purchase consideration

119,137

Aptiv Solutions | Customer Relationships

Business Acquisition [Line Items]

Intangible asset

21,400

Aptiv Solutions | Order Backlog

Business Acquisition [Line Items]

Intangible asset

$ 7,900

[1]	Goodwill represents the acquisition of an established workforce with experience in clinical trial consulting and regulatory support for the development of drugs, medical devices and diagnostics, with a specific focus on strategy to increase efficiency and productivity in product development. Goodwill related to the US portion of the business acquired is tax deductible.
[2]	Adjustments to cash consideration represent certain one-time liabilities (including loan notes) identified at the acquisition date which have subsequently been paid.

Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed of Clinical Trial Services of Cross Country Healthcare Inc. (Detail) - USD ($)
$ in Thousands

1 Months Ended

Feb. 15, 2013

Oct. 31, 2013

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Business Acquisition [Line Items]

Goodwill

$ 588,434

$ 463,324

$ 357,523

Clinical Trial Services of Cross Country Healthcare Inc.

Business Acquisition [Line Items]

Property, plant and equipment

$ 339

Goodwill

^[1]

36,922

Cash and cash equivalents

1,039

Accounts receivable

9,200

Unbilled revenue

2,128

Prepayments and other current assets

465

Non-current assets

Other liabilities

(2,285)

Non-current other liabilities

(16)

Net assets acquired

51,698

Cash consideration

51,897

Working capital adjustment

(199)

$ (199)

Net assets acquired/Net purchase consideration

51,698

Clinical Trial Services of Cross Country Healthcare Inc. | Customer Relationships

Business Acquisition [Line Items]

Intangible asset

3,300

Clinical Trial Services of Cross Country Healthcare Inc. | Order Backlog

Business Acquisition [Line Items]

Intangible asset

$ 600

[1]

Goodwill represents the acquisition of an established workforce with experience in the clinical research industry, thereby allowing the Company to enhance its capabilities in global resourcing and FSP and also medical and safety services. Goodwill related to the US portion of the business acquired is tax deductible.

Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Cost
Foreign exchange movement	$ (5,092)	$ (2,769)
Intangible assets gross	113,381	80,909
Accumulated amortization	(49,587)	(32,120)
Foreign exchange movement	2,333	930
Net book value	66,127	49,719
Customer Relationships
Cost
Intangible assets gross	90,541	36,130
Technology Assets
Cost
Intangible assets gross	11,169	11,169
Order Backlog
Cost
Intangible assets gross	13,592	3,171
Trade Names
Cost
Intangible assets gross	1,357	1,357
Volunteer List Acquired
Cost
Intangible assets gross	1,325	1,325
Non-compete Agreements
Cost
Intangible assets gross	$ 489	489
Aptiv Intangible Asset
Cost
Intangible assets gross		$ 30,037

Intangible Assets - Additional Information (Detail) $ in Thousands	Dec. 04, 2015 USD ($) Site	Feb. 27, 2015 USD ($)	May. 07, 2014 USD ($)	Feb. 15, 2013 USD ($)	Feb. 28, 2012 USD ($)	Feb. 15, 2012 USD ($)	Jul. 14, 2011 USD ($)	Jan. 14, 2011 USD ($)	Nov. 14, 2008 USD ($)	Feb. 11, 2008 USD ($)	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											$ 49,587	$ 32,120
PMG
Indefinite-lived Intangible Assets [Line Items]
Number of clinical research sites acquired \| Site	48
Amount amortized since date of acquisition											170
PMG \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired	$ 10,300
Amortization period	6 years
MediMedia Pharma Solutions
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											4,800
MediMedia Pharma Solutions \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired		$ 22,800
Amortization period		7 years
MediMedia Pharma Solutions \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired		$ 2,500
Amortization period		1 year
Aptiv Solutions
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											9,484
Aptiv Solutions \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired			$ 21,400
Amortization period			7 years
Aptiv Solutions \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired			$ 7,900
Amortization period			3 years
Clinical Trial Services of Cross Country Healthcare Inc.
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											3,763
Clinical Trial Services of Cross Country Healthcare Inc. \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired				$ 3,300
Amortization period				3 years
Clinical Trial Services of Cross Country Healthcare Inc. \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired				$ 600
Amortization period				1 year
PriceSpective
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											4,720
PriceSpective \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired					$ 10,200
Amortization period					10 years
PriceSpective \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired					$ 400
Amortization period					9 months 18 days
PriceSpective \| Non-compete Agreements
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired					$ 400
Amortization period					3 years
BeijingWits Medical
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											1,136
BeijingWits Medical \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired						$ 1,800
Amortization period						10 years
BeijingWits Medical \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired						$ 400
Amortization period						4 years
BeijingWits Medical \| Non-compete Agreements
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired						$ 10
Amortization period						5 years
Firecrest Clinical Limited
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											11,103
Firecrest Clinical Limited \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired							$ 5,200
Amortization period							7 years 6 months
Firecrest Clinical Limited \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired							$ 1,200
Amortization period							1 year 2 months 12 days
Firecrest Clinical Limited \| Technology Assets
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired							$ 11,200
Amortization period							7 years 6 months
Firecrest Clinical Limited \| Trade Names
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired							$ 1,400
Amortization period							4 years 6 months
Oxford Outcomes Limited
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											5,795
Oxford Outcomes Limited \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired								$ 6,600
Amortization period								6 years 6 months
Oxford Outcomes Limited \| Order Backlog
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired								$ 600
Amortization period								2 years
Prevalere Life Sciences
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											5,792
Prevalere Life Sciences \| Customer Lists
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired									$ 7,400
Prevalere Life Sciences \| Minimum \| Customer Lists
Indefinite-lived Intangible Assets [Line Items]
Amortization period									7 years
Prevalere Life Sciences \| Maximum \| Customer Lists
Indefinite-lived Intangible Assets [Line Items]
Amortization period									11 years
Healthcare Discoveries
Indefinite-lived Intangible Assets [Line Items]
Amount amortized since date of acquisition											$ 2,812
Healthcare Discoveries \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired										$ 1,600
Healthcare Discoveries \| Volunteer List Acquired
Indefinite-lived Intangible Assets [Line Items]
Value of amortizable intangible asset acquired										$ 1,300
Healthcare Discoveries \| Minimum \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Amortization period										2 years
Healthcare Discoveries \| Minimum \| Volunteer List Acquired
Indefinite-lived Intangible Assets [Line Items]
Amortization period										6 years
Healthcare Discoveries \| Maximum \| Customer Relationships
Indefinite-lived Intangible Assets [Line Items]
Amortization period										9 years

Future Intangible Asset Amortization Expense (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Finite-Lived Intangible Assets [Line Items]
2016	$ 15,599
2017	12,451
2018	11,034
2019	9,494
2020	9,215
Finite Lived Intangible Assets, Amortization Expense, Net, Total	$ 57,793

Property, Plant and Equipment, Net (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Cost
Land	$ 3,464	$ 3,464
Building	80,861	88,580
Computer equipment and software	282,909	247,980
Office furniture and fixtures	65,152	64,690
Laboratory equipment	31,098	23,599
Leasehold improvements	20,647	19,516
Motor vehicles	47	47
Property, Plant and Equipment, Gross, Total	484,178	447,876
Less accumulated depreciation and asset write offs	(333,960)	(299,691)
Property, plant and equipment (net)	$ 150,218	$ 148,185

Other Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Other Liabilities [Line Items]
Personnel related liabilities	$ 159,339	$ 167,362
Facility related liabilities	22,517	19,862
General overhead liabilities	29,257	33,422
Other liabilities	18,607	26,631
Short term government grants (note 11)	43	110
Restructuring and other items (note 14)	2,116	3,704	$ 9,000
Other liabilities	$ 231,879	$ 251,091

Othere Non-Current Liabilities (Detail) - USD ($)
$ in Thousands

Dec. 31, 2015

Dec. 31, 2014

Schedule of Accrued Liabilities [Line Items]

Personnel related liabilities (note 9)

^[1]

$ 3,187

$ 1,059

Defined benefit pension obligations, net (note 9)

4,002

7,466

Other non-current liabilities

5,035

4,654

Non-current other liabilities

$ 12,224

$ 13,179

[1]	An amount of $764,000 was included within other liabilities in respect of the Company's Swiss pension plan at December 31, 2014. The total pension liability recorded at December 31, 2014 was $1,823,000.

Othere Non-Current Liabilities (Parenthetical) (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Schedule of Accrued Liabilities [Line Items]
Non-current pension liability	$ 4,002	$ 7,466
Total pension liability		1,823
SWITZERLAND \| Foreign Postretirement Benefit Plan
Schedule of Accrued Liabilities [Line Items]
Non-current pension liability		$ 764

Employee Benefits - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	May. 07, 2014
Defined Benefit Plan Disclosure [Line Items]
Discount Rate Description	Certain Company employees are eligible to participate in a defined contribution plan (the "Plan"). Participants in the Plan may elect to defer a portion of their pre-tax earnings into a pension plan, which is run by an independent party. The Company matches participant's contributions typically at 6% of the participant's annual compensation.
Aptiv Solutions
Defined Benefit Plan Disclosure [Line Items]
Percentage of common stock acquired				100.00%
Defined Benefit Plan Contributions
Defined Benefit Plan Disclosure [Line Items]
Contributions percentage of annual compensation	6.00%
Plan participants' contributions	$ 21,874	$ 22,582	$ 20,293
Defined Contribution Pension Plan 401(k)
Defined Benefit Plan Disclosure [Line Items]
Contributions percentage of annual compensation	6.00%
Plan participants' contributions	$ 12,802	10,514	$ 9,816
Participant's contributions percentage	50.00%
Foreign Postretirement Benefit Plan \| UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Plan participants' contributions	$ 26	$ 44
Expected rate of return on plan assets	2.70%	6.10%	5.70%
Expected long term rate of return on bonds Description	Applying the above expected long term rates of return to the asset distribution at December 31, 2015, gives rise to an expected overall rate of return of scheme assets of approximately 3.0% per annum.
Contribution to pension fund in the year ending December 31, 2016	$ 100
Expected benefit cash flow description	The expected cash flows are estimated figures based on the members expected to retire over the next 10 years assuming no early retirements plus an additional amount in respect of recent average withdrawal experience.
Retirement period used as a basis to estimate expected cash flows	10 years
Net gain for the defined benefit pension plan
Prior service cost for the defined benefit pension plan
Foreign Postretirement Benefit Plan \| UNITED KINGDOM \| iboxx Corporate Bonds
Defined Benefit Plan Disclosure [Line Items]
Basis point increase in benefits obligation discount rate	0.30%
Defined benefit plan bond maturity period	15 years
Foreign Postretirement Benefit Plan \| UNITED KINGDOM \| Legal and General over 15 year Gilts Index
Defined Benefit Plan Disclosure [Line Items]
Expected long term rate of return on bonds Description	The long-term expected return on corporate bonds and gilts (fixed interest and index linked) is determined by reference to bond yields and gilt yields at the balance sheet date.
Foreign Postretirement Benefit Plan \| UNITED KINGDOM \| Bonds
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	3.00%
Percentage of investments	70.00%
Foreign Postretirement Benefit Plan \| UNITED KINGDOM \| Corporate Bond Securities
Defined Benefit Plan Disclosure [Line Items]
Expected rate of return on plan assets	4.00%
Percentage of investments	30.00%
Foreign Postretirement Benefit Plan \| SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Plan participants' contributions	$ 216
Expected rate of return on plan assets	1.35%
Foreign Pension Plan \| SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Contribution to pension fund in the year ending December 31, 2016	$ 200

Change in Benefit Obligations (Detail) - Foreign Postretirement Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	$ 32,875	$ 24,958
Service cost	78	91	$ 251
Interest cost	1,140	1,235	1,005
Plan participants' contributions	26	44
Plan curtailments		359
Benefits paid	(1,111)	(68)
Actuarial (gain)/loss	(3,992)	8,270
Foreign currency exchange rate changes	(1,647)	(2,014)
Benefit obligation at end of year	27,369	32,875	$ 24,958
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Benefit obligation at beginning of year	8,884
Service cost	618
Interest cost	159
Plan participants' contributions	216
Benefits paid	(1,146)
Actuarial (gain)/loss	81
Foreign currency exchange rate changes	(1,205)
Benefit obligation at end of year	$ 8,537	$ 8,884

Change in Plan Assets (Detail) - Foreign Postretirement Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	$ 25,409	$ 21,422
Expected return on plan assets	661	1,299	$ 983
Actual return on plan assets	277	5,424
Employer contributions	114	155
Plan participants' contributions	26	44
Benefits paid	(1,111)	(68)
Foreign currency exchange rate changes	(1,348)	(1,568)
Fair value of plan assets at end of year	23,367	25,409	$ 21,422
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets at beginning of year	7,061
Expected return on plan assets	93
Actual return on plan assets	(1,075)
Scheme contributions	194
Plan participants' contributions	216
Benefits paid	(1,146)
Foreign currency exchange rate changes	7
Fair value of plan assets at end of year	$ 5,350	$ 7,061

Funded Status - United Kingdom (Detail) - Foreign Postretirement Benefit Plan - UNITED KINGDOM - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ (27,369)	$ (32,875)
Fair value of plan assets	23,367	25,409	$ 21,422
Funded status	(4,002)	(7,466)
Non-current other liabilities (note 8)	$ (4,002)	$ (7,466)

Components of Net Periodic Benefit Cost (Detail) - Foreign Postretirement Benefit Plan - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 78	$ 91	$ 251
Interest cost	1,140	1,235	1,005
Expected return on plan assets	(661)	(1,299)	(983)
Amortization of net loss	224	20	130
Curtailment loss		359
Net periodic benefit cost	781	$ 406	$ 403
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Service cost	618
Interest cost	159
Expected return on plan assets	(93)
SWITZERLAND \| Includes Financial Instruments, Property Occupied by, or Other Assets
Defined Benefit Plan Disclosure [Line Items]
Service cost	402
Interest cost	159
Expected return on plan assets	(119)
Settlement loss	18
Net periodic benefit cost	$ 460

Net Periodic Pension Benefit Cost Assumptions (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Total	$ (2,693)	$ 4,125	$ (1,383)
Foreign Postretirement Benefit Plan \| UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Discount rate	3.60%	4.70%	4.60%
Rate of compensation increase	3.60%	4.00%	3.40%
Expected rate of return on plan assets	2.70%	6.10%	5.70%
Actuarial (gain)/loss - benefit obligation	$ (3,992)	$ 8,270	$ 680
Actuarial loss/(gain) - plan assets	384	(4,125)	(1,933)
Actuarial gain recognized in net periodic benefit cost	(224)	(20)	(130)
Total	$ (3,832)	$ 4,125	$ (1,383)
Foreign Postretirement Benefit Plan \| SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Discount rate	1.35%
Rate of compensation increase	2.00%
Expected rate of return on plan assets	1.35%
Actuarial (gain)/loss - benefit obligation	$ 81
Actuarial loss/(gain) - plan assets	1,075
Prior service cost recognized in net periodic benefit cost	(17)
Total	$ 1,139

Amounts recognized in accumulated other comprehensive income that have not been recognized (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Total	$ 3,420	$ 6,113
Foreign Postretirement Benefit Plan \| UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Net actuarial loss	2,281	6,113	$ 1,988
Total	$ 2,281	$ 6,113	$ 1,988

Assumptions Used in Determining Benefit Obligation (Detail) - Foreign Postretirement Benefit Plan	Dec. 31, 2015	Dec. 31, 2014
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Discount rate	4.00%	3.60%
Rate of compensation increase	3.70%	3.60%
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Discount rate	0.95%
Rate of compensation increase	2.00%

Expected Long Term Rates of Return on Different Asset Classes (Detail) - Foreign Postretirement Benefit Plan - UNITED KINGDOM	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return per annum	2.70%	6.10%	5.70%
Corporate Bond Securities
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return per annum	4.00%
Gilts
Defined Benefit Plan Disclosure [Line Items]
Expected long-term return per annum	2.60%

Actual Plan Asset Allocation (Detail) - Foreign Postretirement Benefit Plan	Dec. 31, 2015	Dec. 31, 2014
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	100.00%	100.00%
UNITED KINGDOM \| Corporate Bond Securities
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	26.00%	26.00%
UNITED KINGDOM \| Gilts
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	74.00%	74.00%
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	100.00%
SWITZERLAND \| Equity
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	1.00%
SWITZERLAND \| Bonds
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	75.00%
SWITZERLAND \| Real Estate
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	12.00%
SWITZERLAND \| Other
Defined Benefit Plan Disclosure [Line Items]
Actual plan asset allocations	12.00%

Plan Asset Fair Value Measurements (Detail) - Foreign Postretirement Benefit Plan - UNITED KINGDOM - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 23,367	$ 25,409	$ 21,422
Fair Value, Inputs, Level 1
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	23,367	25,409
Fair Value, Inputs, Level 1 \| Cash
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	3	16
Fair Value, Inputs, Level 1 \| Fixed Income Securities \| Legal and General Active Corporate Bond Over - 10 Year
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,256	6,560
Fair Value, Inputs, Level 1 \| Fixed Income Securities \| Legal and General Gilt Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	6,528	6,977
Fair Value, Inputs, Level 1 \| Fixed Income Securities \| Legal and General Index Linked Gilt Funds
Defined Benefit Plan Disclosure [Line Items]
Fair value of plan assets	$ 10,580	$ 11,856

Annual Benefit Payments (Detail) - Foreign Postretirement Benefit Plan $ in Thousands	Dec. 31, 2015 USD ($)
UNITED KINGDOM
Defined Benefit Plan Disclosure [Line Items]
Expected future benefit payments in 2016	$ 66
Expected future benefit payments in 2017	68
Expected future benefit payments in 2018	71
Expected future benefit payments in 2019	72
Expected future benefit payments in 2020	75
Expected future benefit payments in Years 2021 - 2025	376
SWITZERLAND
Defined Benefit Plan Disclosure [Line Items]
Expected future benefit payments in 2016	166
Expected future benefit payments in 2017	169
Expected future benefit payments in 2018	171
Expected future benefit payments in 2019	182
Expected future benefit payments in 2020	182
Expected future benefit payments in Years 2021 - 2025	$ 1,205

Funded Status - Switzerland (Detail) - Foreign Postretirement Benefit Plan - SWITZERLAND - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Projected benefit obligation	$ 8,537
Fair value of plan assets	(5,350)	$ (7,061)
Funded status	3,187
Non-current other liabilities (note 8)	$ 3,187

Equity Incentive Schemes and Stock Compensation Charges - Additional Information (Detail) - USD ($) $ in Thousands		12 Months Ended			36 Months Ended
	May. 11, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015	Dec. 31, 2016
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding		4 years 9 months 4 days	4 years 6 months 29 days
Exercisable - weighted average remaining contractual life		3 years 4 months 21 days	3 years 2 months 19 days
Options expected to vest		494,951			494,951
Intrinsic value of option exercised		$ 34,200
Intrinsic value of option outstanding		69,700			$ 69,700
Intrinsic value of option exercisable		35,200			35,200
Share-based compensation expense		33,317	$ 22,742	$ 14,220
Non-cash stock compensation expense not yet recognized		$ 61,900			$ 61,900
Unrecognized stock-based compensation expense, weighted average period (years)		2 years 18 days
Tax benefit on exercise of options		$ 1,905	2,404	1,651
Income tax expense related to stock compensation		1,500	1,500
Cash tax benefit related to stock options exercised		$ 5,600	3,900
Scenario, Forecast
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options expected to vest						336,993
Employee Stock Plan, 2008 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance		6,000,000			6,000,000
Employee Stock Plan, 2008 Plan \| Individual Employee
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance		400,000			400,000
Employee Stock Plan, 2008 Plan \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Percentage of option price for fair value of ordinary share		100.00%
Employee Stock Plan, 2003 Plan
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance		6,000,000			6,000,000
Maximum number of award as percentage of shares outstanding		10.00%
Employee Stock Plan, 2003 Plan \| Individual Employee
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance		400,000			400,000
Employee Stock Option
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Shares vesting period		5 years
Shares expiration period		8 years
Cash tax benefit related to stock options exercised		$ 21,000	22,300	$ 27,000
Employee Stock Option \| Vested and Unvested Options
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Options vesting percentage		20.00%
Employee Stock Option \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Weighted average contractual term of options outstanding		8 years
Restricted Stock Units 2008
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance		1,000,000			1,000,000
Restricted Stock Units 2013
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Ordinary shares which have been reserved for issuance	4,100,000
Number of additional shares authorized for issuance	2,500,000
Restricted Stock Units (RSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested		$ 7,000	$ 4,900
Stock units vested		268,870
Stock units granted		389,542
Performance Share Unit (PSUs)
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Fair value of stock units vested		$ 300
Stock units vested		7,990	0
Stock units granted		259,110
PSUs Based on Service and EPS Targets
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units granted					456,922
PSUs Based on Service and EPS Targets \| Minimum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Cumulative EPS vesting period		2013
PSUs Based on Service and EPS Targets \| Maximum
Compensation Related Costs Share Based Payments Disclosure [Line Items]
Stock units to be granted		444,851			444,851
Cumulative EPS vesting period		2017

Summary of Stock Option Activity (Detail) - Stock Option And Award Plans - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Options Granted Under Plans
Beginning balance	2,227,700	2,973,788	4,350,631
Granted	259,059	366,985	264,950
Exercised	(773,753)	(926,407)	(1,249,759)
Cancelled	(86,424)	(186,666)	(392,034)
Ending Balance	1,626,582	2,227,700	2,973,788
Vested and exercisable at end of period	657,729
Number of Shares
Beginning balance	2,227,700	2,973,788	4,350,631
Granted	259,059	366,985	264,950
Exercised	(773,753)	(926,407)	(1,249,759)
Cancelled	(86,424)	(186,666)	(392,034)
Ending balance	1,626,582	2,227,700	2,973,788
Vested and exercisable at end of period	657,729
Weighted Average Exercise Price
Beginning balance	$ 28.00	$ 24.20	$ 23.01
Granted	68.25	45.82	33.09
Exercised	27.13	24.02	21.60
Cancelled	27.32	22.17	25.27
Ending balance	34.87	28.00	24.20
Vested and exercisable at end of period	24.15
Weighted Average Grant Date Fair Value
Beginning balance	10.40	9.57	9.17
Granted	19.75	14.09	12.05
Exercised	10.31	9.45	8.58
Cancelled	10.31	9.01	10.02
Ending balance	11.94	$ 10.40	$ 9.57
Vested and exercisable at end of period	$ 9.36

Summary of Movement in Non-Vested Share Options (Detail) - Employee Stock Option - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Options Outstanding Number of Shares
Beginning Balance	1,203,150
Granted	259,059
Vested	(379,992)
Forfeited	(113,364)
Ending Balance	968,853	1,203,150
Weighted Average Exercise Price
Beginning balance	$ 30.54
Granted	68.25
Vested	28.25
Forfeited	25.21
Ending balance	42.14	$ 30.54
Weighted Average Fair Value
Beginning Balance	10.98
Granted	19.75	14.09	$ 12.05
Vested	10.49
Forfeited	9.50
Ending Balance	$ 13.69	$ 10.98

Outstanding and Exercisable Share Options (Detail)	12 Months Ended
Outstanding and Exercisable Share Options (Detail)	Dec. 31, 2015 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 15.84
Range Exercise Price Minimum	$ 68.39
Options Outstanding Number of Shares \| shares	1,626,582
Options Outstanding Weighted Average Remaining Contractual Life	4 years 9 months 4 days
Options Outstanding Weighted Average Exercise Price	$ 34.87
Options Exercisable Number of Shares \| shares	657,729
Options Exercisable Weighted Average Exercise Price	$ 24.15
Range 1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 15.84
Options Outstanding Number of Shares \| shares	50,000
Options Outstanding Weighted Average Remaining Contractual Life	1 year 3 months 29 days
Options Outstanding Weighted Average Exercise Price	$ 15.84
Options Exercisable Number of Shares \| shares	50,000
Options Exercisable Weighted Average Exercise Price	$ 15.84
Range 2
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 16.80
Options Outstanding Number of Shares \| shares	60,000
Options Outstanding Weighted Average Remaining Contractual Life	3 years 9 months 29 days
Options Outstanding Weighted Average Exercise Price	$ 16.80
Options Exercisable Number of Shares \| shares	30,000
Options Exercisable Weighted Average Exercise Price	$ 16.80
Range 3
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 17.17
Options Outstanding Number of Shares \| shares	12,000
Options Outstanding Weighted Average Remaining Contractual Life	3 years 10 months 6 days
Options Outstanding Weighted Average Exercise Price	$ 17.17
Options Exercisable Number of Shares \| shares	6,000
Options Exercisable Weighted Average Exercise Price	$ 17.17
Range 4
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 18.98
Options Outstanding Number of Shares \| shares	600
Options Outstanding Weighted Average Remaining Contractual Life	10 months 13 days
Options Outstanding Weighted Average Exercise Price	$ 18.98
Options Exercisable Number of Shares \| shares	600
Options Exercisable Weighted Average Exercise Price	$ 18.98
Range 5
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 20.16
Options Outstanding Number of Shares \| shares	400
Options Outstanding Weighted Average Remaining Contractual Life	2 years 10 months 17 days
Options Outstanding Weighted Average Exercise Price	$ 20.16
Options Exercisable Number of Shares \| shares	400
Options Exercisable Weighted Average Exercise Price	$ 20.16
Range 6
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 20.28
Options Outstanding Number of Shares \| shares	255,694
Options Outstanding Weighted Average Remaining Contractual Life	3 years 2 months 1 day
Options Outstanding Weighted Average Exercise Price	$ 20.28
Options Exercisable Number of Shares \| shares	158,073
Options Exercisable Weighted Average Exercise Price	$ 20.28
Range 7
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 20.59
Options Outstanding Number of Shares \| shares	57,200
Options Outstanding Weighted Average Remaining Contractual Life	4 years 1 month 21 days
Options Outstanding Weighted Average Exercise Price	$ 20.59
Options Exercisable Number of Shares \| shares	4,000
Options Exercisable Weighted Average Exercise Price	$ 20.59
Range 8
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 22.26
Options Outstanding Number of Shares \| shares	61,755
Options Outstanding Weighted Average Remaining Contractual Life	1 year 1 month 24 days
Options Outstanding Weighted Average Exercise Price	$ 22.26
Options Exercisable Number of Shares \| shares	61,755
Options Exercisable Weighted Average Exercise Price	$ 22.26
Range 9
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 22.30
Options Outstanding Number of Shares \| shares	250,939
Options Outstanding Weighted Average Remaining Contractual Life	4 years 3 months 26 days
Options Outstanding Weighted Average Exercise Price	$ 22.30
Options Exercisable Number of Shares \| shares	109,894
Options Exercisable Weighted Average Exercise Price	$ 22.30
Range 10
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 23.66
Options Outstanding Number of Shares \| shares	7,890
Options Outstanding Weighted Average Remaining Contractual Life	4 years 6 months 29 days
Options Outstanding Weighted Average Exercise Price	$ 23.66
Options Exercisable Number of Shares \| shares	4,450
Options Exercisable Weighted Average Exercise Price	$ 23.66
Range 11
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 24.46
Options Outstanding Number of Shares \| shares	101,412
Options Outstanding Weighted Average Remaining Contractual Life	2 years 2 months 5 days
Options Outstanding Weighted Average Exercise Price	$ 24.46
Options Exercisable Number of Shares \| shares	101,412
Options Exercisable Weighted Average Exercise Price	$ 24.46
Range 12
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 26.20
Options Outstanding Number of Shares \| shares	1,950
Options Outstanding Weighted Average Remaining Contractual Life	2 years 4 months 21 days
Options Outstanding Weighted Average Exercise Price	$ 26.20
Options Exercisable Number of Shares \| shares	1,950
Options Exercisable Weighted Average Exercise Price	$ 26.20
Range 13
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 26.71
Options Outstanding Number of Shares \| shares	4,450
Options Outstanding Weighted Average Remaining Contractual Life	4 years 10 months 10 days
Options Outstanding Weighted Average Exercise Price	$ 26.71
Options Exercisable Number of Shares \| shares	2,670
Options Exercisable Weighted Average Exercise Price	$ 26.71
Range 14
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 29.45
Options Outstanding Number of Shares \| shares	3,000
Options Outstanding Weighted Average Remaining Contractual Life	2 years 3 months 29 days
Options Outstanding Weighted Average Exercise Price	$ 29.45
Options Exercisable Number of Shares \| shares	3,000
Options Exercisable Weighted Average Exercise Price	$ 29.45
Range 15
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 32.37
Options Outstanding Number of Shares \| shares	179,603
Options Outstanding Weighted Average Remaining Contractual Life	5 years 4 months 2 days
Options Outstanding Weighted Average Exercise Price	$ 32.37
Options Exercisable Number of Shares \| shares	70,997
Options Exercisable Weighted Average Exercise Price	$ 32.37
Range 16
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 35.33
Options Outstanding Number of Shares \| shares	1,350
Options Outstanding Weighted Average Remaining Contractual Life	1 month 28 days
Options Outstanding Weighted Average Exercise Price	$ 35.33
Options Exercisable Number of Shares \| shares	1,350
Options Exercisable Weighted Average Exercise Price	$ 35.33
Range 17
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 36.22
Options Outstanding Number of Shares \| shares	27,213
Options Outstanding Weighted Average Remaining Contractual Life	5 years 5 months 19 days
Options Outstanding Weighted Average Exercise Price	$ 36.22
Options Exercisable Number of Shares \| shares	7,908
Options Exercisable Weighted Average Exercise Price	$ 36.22
Range 18
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 37.90
Options Outstanding Number of Shares \| shares	7,100
Options Outstanding Weighted Average Remaining Contractual Life	5 years 11 months 5 days
Options Outstanding Weighted Average Exercise Price	$ 37.90
Options Exercisable Number of Shares \| shares	920
Options Exercisable Weighted Average Exercise Price	$ 37.90
Range 19
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 40.83
Options Outstanding Number of Shares \| shares	105,992
Options Outstanding Weighted Average Remaining Contractual Life	6 years 4 months 24 days
Options Outstanding Weighted Average Exercise Price	$ 40.83
Options Exercisable Number of Shares \| shares	20,468
Options Exercisable Weighted Average Exercise Price	$ 40.83
Range 20
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 47.03
Options Outstanding Number of Shares \| shares	71,670
Options Outstanding Weighted Average Remaining Contractual Life	6 years 2 months 5 days
Options Outstanding Weighted Average Exercise Price	$ 47.03
Options Exercisable Number of Shares \| shares	7,520
Options Exercisable Weighted Average Exercise Price	$ 47.03
Range 21
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 48.67
Options Outstanding Number of Shares \| shares	140,881
Options Outstanding Weighted Average Remaining Contractual Life	6 years 2 months 16 days
Options Outstanding Weighted Average Exercise Price	$ 48.67
Options Exercisable Number of Shares \| shares	13,556
Options Exercisable Weighted Average Exercise Price	$ 48.67
Range 22
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 51.35
Options Outstanding Number of Shares \| shares	4,030
Options Outstanding Weighted Average Remaining Contractual Life	6 years 7 months 10 days
Options Outstanding Weighted Average Exercise Price	$ 51.35
Options Exercisable Number of Shares \| shares	806
Options Exercisable Weighted Average Exercise Price	$ 51.35
Range 23
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 66.47
Options Outstanding Number of Shares \| shares	15,969
Options Outstanding Weighted Average Remaining Contractual Life	7 years 4 months 21 days
Options Outstanding Weighted Average Exercise Price	$ 66.47
Options Exercisable Weighted Average Exercise Price	66.47
Range 24
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 66.97
Options Outstanding Number of Shares \| shares	3,118
Options Outstanding Weighted Average Remaining Contractual Life	7 years 5 months 16 days
Options Outstanding Weighted Average Exercise Price	$ 66.97
Options Exercisable Weighted Average Exercise Price	66.97
Range 25
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Range Exercise Price Maximum	$ 68.39
Options Outstanding Number of Shares \| shares	232,366
Options Outstanding Weighted Average Remaining Contractual Life	7 years 2 months 19 days
Options Outstanding Weighted Average Exercise Price	$ 68.39
Options Exercisable Weighted Average Exercise Price	$ 68.39

Schedule of Weighted Average Fair Values and Assumptions Used (Detail) - Employee Stock Option - $ / shares	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average fair value	$ 19.75	$ 14.09	$ 12.05
Assumptions:
Expected volatility	30.00%	32.00%	40.00%
Dividend yield	0.00%	0.00%	0.00%
Risk-free interest rate	1.58%	1.57%	0.76%
Expected life	5 years	5 years	5 years

Summary of RSU and PSU Activity (Detail) - $ / shares	12 Months Ended
Summary of RSU and PSU Activity (Detail) - $ / shares	Dec. 31, 2015	Dec. 31, 2014
Performance Share Unit (PSUs)
Outstanding Number of Shares
Outstanding at beginning of period	669,171
Granted	259,110
Shares vested	(7,990)	0
Forfeited	(18,518)
Outstanding at ending of period	901,773	669,171
Weighted Average Fair Value
Outstanding at beginning of period	$ 39.78
Granted	68.82
Shares vested	32.38
Forfeited	46.82
Outstanding at end of period	$ 72.55	$ 39.78
Weighted Average Remaining Contractual Life
Outstanding at end of period	2 years 5 months 27 days	1 year 9 months 7 days
Restricted Stock Units (RSUs)
Outstanding Number of Shares
Outstanding at beginning of period	1,038,996
Granted	389,542
Shares vested	(268,870)
Forfeited	(92,055)
Outstanding at ending of period	1,067,613	1,038,996
Weighted Average Fair Value
Outstanding at beginning of period	$ 35.19
Granted	67.02
Shares vested	26.06
Forfeited	44.43
Outstanding at end of period	$ 48.30	$ 35.19
Weighted Average Remaining Contractual Life
Outstanding at end of period	1 year 5 months 23 days	1 year 8 months 1 day

Schedule of Non-cash Stock Compensation Expense (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 33,317	$ 22,742	$ 14,220
Direct costs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	18,358	12,531	7,835
Selling, general and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 14,959	$ 10,211	$ 6,385

Government Grants (Detail) - USD ($) $ in Thousands	12 Months Ended
Government Grants (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Government Grants [Line Items]
Received	$ 3,539	$ 3,698
Less accumulated amortization	(2,657)	(2,710)
Foreign exchange translation adjustment	120	238
Total government grants	1,002	1,226
Less current portion	(43)	(110)
Non-current government grants	$ 959	$ 1,116

Government Grants - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Government Grants [Line Items]
Amortization of government grants	$ (53)	$ 213	$ 349
Restricted retained earnings	$ 700

Share Capital - Additional Information (Detail) - USD ($)								12 Months Ended
	Jul. 31, 2015	May. 01, 2015	Sep. 19, 2014	Jul. 30, 2012	Apr. 27, 2012	Feb. 21, 2012	Nov. 22, 2011	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Oct. 27, 2011
Equity, Class of Treasury Stock [Line Items]
Share allotment description								Every holder of an ordinary share present in person or proxy at a general meeting of shareholders shall have one vote, for each ordinary share held with no individual having more than one vote.
Total proceeds from exercise of stock options by employees								$ 5,600,000	$ 3,900,000
Ordinary shares redeemed, value			$ 40,000,000					$ 457,892,000	$ 140,030,000
Ordinary shares repurchased									2,640,610	0
Ordinary shares repurchased, value									$ 140,000,000
Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value											$ 50,000,000
Share repurchase program value, additional			$ 100,000,000
Employee Stock Option
Equity, Class of Treasury Stock [Line Items]
Options exercised by employees								773,753	926,407	1,249,759
Average exercise price of Option per share								$ 27.13	$ 24.02	$ 21.60
Total proceeds from exercise of stock options by employees								$ 21,000,000	$ 22,300,000	$ 27,000,000
Restricted Stock Units (RSUs)
Equity, Class of Treasury Stock [Line Items]
Ordinary shares issued in respect of certain RSU's previously awarded by the Company								268,870	233,726	50,000
Performance Share Unit (PSUs)
Equity, Class of Treasury Stock [Line Items]
Ordinary shares issued in respect of certain PSUs previously awarded by the Company								7,990
Buyback Program
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value	$ 400,000,000	$ 60,000,000
Ordinary shares redeemed	5,316,062	882,419						6,198,481
Ordinary shares redeemed, value	$ 400,000,000	$ 57,900,000						$ 457,900,000
Plan 1
Equity, Class of Treasury Stock [Line Items]
Share repurchase plans, start date							Nov. 23, 2011
Share repurchase plans, end date							Dec. 31, 2011
Plan 1 \| Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value							$ 10,000,000
Plan 2
Equity, Class of Treasury Stock [Line Items]
Share repurchase plans, start date							Jan. 01, 2012
Share repurchase plans, end date							Feb. 20, 2012
Plan 2 \| Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value							$ 10,000,000
Plan 3
Equity, Class of Treasury Stock [Line Items]
Share repurchase plans, start date						Feb. 22, 2012
Share repurchase plans, end date						Apr. 22, 2012
Plan 3 \| Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value						$ 20,000,000
Plan 4
Equity, Class of Treasury Stock [Line Items]
Share repurchase plans, start date					Apr. 27, 2012
Share repurchase plans, end date					Jul. 18, 2012
Plan 4 \| Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value					$ 20,000,000
Plan 5
Equity, Class of Treasury Stock [Line Items]
Share repurchase plans, start date				Jul. 30, 2012
Share repurchase plans, end date				Oct. 26, 2012
Plan 5 \| Maximum
Equity, Class of Treasury Stock [Line Items]
Share repurchase program value				$ 10,000,000

Components of Income Before Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	$ 278,850	$ 202,716	$ 120,865
Ireland
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	184,643	143,889	80,914
United States
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	15,436	6,966	16,218
Other
Schedule of Components of Income Before Income Tax Expense (Benefit) [Line Items]
Income before provision for income taxes	$ 78,771	$ 51,861	$ 23,733

Components of Provision for Income Taxes (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current tax expense:
Current tax expense	$ 36,154	$ 38,148	$ 28,526
Deferred expense/(benefit):
Deferred tax expense/(benefit)	3,157	(7,900)	(10,473)
Provision for income taxes	39,311	30,248	18,053
Impact on shareholders equity and other comprehensive income of the tax consequence of :
Excess tax benefit on stock compensation	(1,905)	(2,404)	(1,651)
Currency impact on long term funding	3,574	178	87
Total	40,980	28,022	16,489
Ireland
Current tax expense:
Current tax expense	21,769	19,562	9,158
Deferred expense/(benefit):
Deferred tax expense/(benefit)	26	(1,178)	1,914
Provision for income taxes	21,795	18,384	11,073
United States
Current tax expense:
Current tax expense	684	7,891	14,492
Deferred expense/(benefit):
Deferred tax expense/(benefit)	2,896	(3,031)	(9,420)
Provision for income taxes	3,580	4,860	5,072
Other
Current tax expense:
Current tax expense	13,701	10,695	4,876
Deferred expense/(benefit):
Deferred tax expense/(benefit)	235	(3,691)	(2,967)
Provision for income taxes	$ 5,929	$ 4,149	$ 1,915

Income Taxes - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Irish statutory rate	12.50%	12.50%	12.50%
Valuation allowance for deferred tax assets	$ 17,184	$ 23,145	$ 24,348
Net change in the total valuation allowance	(5,900)	(1,200)
Deferred tax expense/(benefit) resulted from valuation allowance release	3,200	3,100
Unrecognized tax benefit, potentially expire in 2016	3,800
Increase related to acquired tax positions	778	14,552
Total unrecognized tax benefits net of potential benefits	28,200	23,200	5,800
Interest and penalties recognized as an expense	900	200	$ 200
Total accrued interest and penalties	$ 3,300	2,400
Tax Jurisdiction Description	In the United States tax periods open to audit include the years ended December 31, 2012, December 31, 2013, December 31, 2014 and December 31, 2015. In Ireland, tax periods open to audit include the years ended December 31, 2011, December 31, 2012, December 31, 2013, December 31, 2014 and December 31, 2015. During such audits, local tax authorities may challenge the positions taken by us in tax returns.
Provision for income taxes
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net change in the total valuation allowance	$ (4,100)	(2,000)
Other Comprehensive Income
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Net change in the total valuation allowance	(1,800)	800
Foreign Country
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Non-U.S subsidiaries operating loss carryforwards for income tax	68,600	95,600
Non-U.S subsidiaries tax credit carryforwards for income tax	5,900	$ 3,600
Additional operating loss carryforward	$ 6,300
Expiration period	Expire between 2016 and 2022
Ireland
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Irish statutory rate	12.50%
United States
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Expiration period	Expire between 2016 and 2035
U.S. Federal net operating loss carry forwards currently available for offset	$ 26,700
Limitation description	Due to changes of ownership in 2000, 2010 and 2014, as defined by Section 382 of the Internal Revenue Code of 1986, as amended.
Alternative minimum tax credit carry forwards	$ 300
Business credit carry forwards that are available to offset	300
United States \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	51,617
U.S. federal net operating loss carry forwards	29,200
United States \| Additional Paid-in Capital \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	16,300
United States \| 2015 \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	4,200
United States \| 2016 - 2018 \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	4,200
United States \| 2019 \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	2,900
United States \| 2020 - 2023 \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	2,000
United States \| 2024 \| Federal
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
U.S. federal net operating loss carry forwards	1,200
United States \| State
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	89,780
United States \| State \| Additional Paid-in Capital
Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items]
Additional operating loss carryforward	$ 17,300

Consolidated Reported Provision for Income Taxes Differed from Statutory Rate (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Taxes at Irish statutory rate of 12.5% (2014:12.5%; 2013:12.5%)	$ 34,856	$ 25,340	$ 15,108
Foreign and other income taxed at higher rates	4,614	3,152	4,873
Research & development tax incentives	(695)	(1,810)	(2,598)
Movement in valuation allowance	(4,133)	(1,965)	2,389
Effects of change in tax rates	(16)	543	1,553
Increase/(decrease) in unrecognized tax benefits xxx	5,085	2,869	(1,409)
Effects of permanent items	(463)	2,048	(1,790)
Other	63	71	(73)
Provision for income taxes	$ 39,311	$ 30,248	$ 18,053

Consolidated Reported Provision for Income Taxes Differed from Statutory Rate (Parenthetical) (Detail)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Irish statutory rate	12.50%	12.50%	12.50%

Tax Effects of Temporary Differences That Gives Rise to Significant Portions of Deferred Tax Assets and Liabilities (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Deferred tax liabilities:
Property, plant and equipment	$ 2,665	$ 4,270	$ 6,501
Goodwill	21,571	18,645	14,013
Other intangible assets	7,369	3,657	970
Other	1,293	1,947	1,111
Total deferred tax liabilities recognized	32,898	28,519	22,595
Deferred tax assets:
Operating loss and tax credits carryforwards	22,186	30,586	29,696
Property, plant and equipment	4,818	4,002	2,739
Accrued expenses and payments on account	29,473	37,620	30,136
Stock compensation	12,959	8,717	6,291
Deferred compensation expense	2,174	1,853	1,187
Other	566	1,244	92
Total deferred tax assets	72,176	84,022	70,141
Valuation allowance for deferred tax assets	(17,184)	(23,145)	(24,348)
Deferred tax assets recognized	54,992	60,877	45,793
Overall net deferred tax asset	$ 22,094	$ 32,358	$ 23,198

Expected Expiry Dates of NOI's (Detail) - United States $ in Thousands	Dec. 31, 2015 USD ($)
Federal
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	$ 51,617
Federal \| Expiring 2016-2017
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	565
Federal \| Expiring 2023-2033
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	34,800
Federal \| Expiring 2035
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	16,252
State
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	89,780
State \| Expiring 2023-2033
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	63,793
State \| Expiring 2035
Operating Loss Carryforwards [Line Items]
Net operating loss carryforward	$ 25,987

Reconciliation of Beginning and Ending Amount of Total Unrecognized Tax Benefits (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Income Tax Contingency [Line Items]
Unrecognized tax benefits at start of year	$ 23,201	$ 5,780	$ 7,189
Increase related to acquired tax positions	778	14,552
Increase related to prior year tax positions	1,482	565
Decrease related to prior year tax positions		(183)	(494)
Increase related to current year tax positions	3,063	3,709	2,269
Settlements	(315)	(2)	(899)
Lapse of statute of limitations	(43)	(1,220)	(2,285)
Unrecognized tax benefits at end of year	$ 28,166	$ 23,201	$ 5,780

Recognized Restructuring and Other Items, Net (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 8,796	$ 9,033
Net charge	$ 8,796	$ 9,033

Restructuring and Other Items - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2015
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 8,796	$ 9,033
Restructuring and other items	3,704	$ 9,000	$ 2,116
Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Restructuring charges	8,796
Manchester, United Kingdom facility closure \| Asset Impairment
Restructuring Cost and Reserve [Line Items]
Restructuring charges	5,629
Manchester, United Kingdom facility closure \| Onerous Lease
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 3,167

Restructuring Charges (Detail) - USD ($) $ in Thousands	12 Months Ended
Restructuring Charges (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Total provision recognized		$ 8,796	$ 9,033
Closing provision	$ 116	537	$ 2,194
Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Total provision recognized		8,796
Utilized	(1,167)
Asset write-off		(5,629)
Closing provision	2,000	3,167
Onerous Lease \| Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Total provision recognized		3,167
Utilized	(1,167)
Closing provision	$ 2,000	3,167
Asset Impairment \| Manchester, United Kingdom facility closure
Restructuring Cost and Reserve [Line Items]
Total provision recognized		5,629
Asset write-off		$ (5,629)

Details of Movement in Restructuring Provisions Recognized (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Restructuring Cost and Reserve [Line Items]
Initial provision recognized		$ 8,796	$ 9,033
Cash payments	$ (82)	(1,656)	(6,743)
Amounts released	(339)		(93)
Foreign exchange movement		(1)	(3)
Closing provision	116	537	2,194
1st Quarter 2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			4,412
2nd Quarter 2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			4,621
Workforce Reduction
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			8,131
Cash payments	(82)	(1,319)	(6,544)
Amounts released			(93)
Foreign exchange movement		(1)	(3)
Closing provision	89	171	1,491
Workforce Reduction \| 1st Quarter 2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			3,903
Workforce Reduction \| 2nd Quarter 2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			4,228
Office Consolidations
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			902
Cash payments		(337)	(199)
Amounts released	(339)
Closing provision	$ 27	$ 366	703
Office Consolidations \| 1st Quarter 2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			509
Office Consolidations \| 2nd Quarter 2013 Restructuring Plan
Restructuring Cost and Reserve [Line Items]
Initial provision recognized			$ 393

Provision for Doubtful Debts (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Accounts, Notes, Loans and Financing Receivable [Line Items]
Opening provision	$ 5,458	$ 3,148
Amounts used during the year	(161)	(502)
Amounts provided during the year	7,572	2,874
Amounts released during the year	(2,244)	(62)
Translation	(242)
Closing provision	$ 10,383	$ 5,458

Commitments and Contingencies - Additional Information (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating Leased Assets [Line Items]
Non-cancelable operating leases for facilities expiration period	10 years
Operating leases rental expense	$ 49.9	$ 54.3	$ 54.9

Future Minimum Rental Commitments for Operating Leases (Detail) $ in Thousands	Dec. 31, 2015 USD ($)
Operating Leased Assets [Line Items]
2016	$ 36,921
2017	26,784
2018	20,547
2019	15,502
2020	11,974
Thereafter	45,924
Total	$ 157,652

Distribution of Net Revenue by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Net Revenue	$ 1,574,978	$ 1,503,316	$ 1,336,058
Ireland
Segment Reporting Information [Line Items]
Net Revenue	429,631	360,376	272,683
Rest Of Europe
Segment Reporting Information [Line Items]
Net Revenue	330,487	372,634	333,543
United States
Segment Reporting Information [Line Items]
Net Revenue	650,941	605,815	582,250
Other
Segment Reporting Information [Line Items]
Net Revenue	$ 163,919	$ 164,491	$ 147,582

Distribution of Income from Operations, including Restructuring and Other Items, by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Income from operations	$ 281,536	$ 202,350	$ 121,167
Ireland
Segment Reporting Information [Line Items]
Income from operations	189,035	138,185	81,811
Rest Of Europe
Segment Reporting Information [Line Items]
Income from operations	38,166	14,481	2,831
United States
Segment Reporting Information [Line Items]
Income from operations	45,320	39,058	29,472
Other
Segment Reporting Information [Line Items]
Income from operations	$ 9,015	$ 10,626	$ 7,053

Distribution of Income from Operations, excluding Restructuring and Other Items, by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	$ 281,536	$ 211,146	$ 130,200
Ireland
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	189,035	138,185	82,867
Rest Of Europe
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	38,166	23,277	6,269
United States
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	45,320	39,058	33,564
Other
Segment Reporting Information [Line Items]
Income from operations, excluding restructuring and other items	$ 9,015	$ 10,626	$ 7,500

Distribution of Property, Plant and Equipment, Net, by Geographical Area (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 150,218	$ 148,185
Ireland
Segment Reporting Information [Line Items]
Property, plant and equipment, net	101,736	95,574
Rest Of Europe
Segment Reporting Information [Line Items]
Property, plant and equipment, net	7,334	10,419
United States
Segment Reporting Information [Line Items]
Property, plant and equipment, net	34,520	33,978
Other
Segment Reporting Information [Line Items]
Property, plant and equipment, net	$ 6,628	$ 8,214

Distribution of Depreciation and Amortization by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 57,677	$ 52,542	$ 46,514
Ireland
Segment Reporting Information [Line Items]
Depreciation and amortization	22,100	20,731	19,826
Rest Of Europe
Segment Reporting Information [Line Items]
Depreciation and amortization	11,055	7,478	6,595
United States
Segment Reporting Information [Line Items]
Depreciation and amortization	20,106	20,491	16,233
Other
Segment Reporting Information [Line Items]
Depreciation and amortization	$ 4,416	$ 3,842	$ 3,860

Distribution of Total Assets by Geographical Area (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Assets	$ 1,718,903	$ 1,528,850
Ireland
Segment Reporting Information [Line Items]
Assets	664,754	495,747
Rest Of Europe
Segment Reporting Information [Line Items]
Assets	343,733	324,086
United States
Segment Reporting Information [Line Items]
Assets	641,769	648,559
Other
Segment Reporting Information [Line Items]
Assets	$ 68,647	$ 60,458

Distribution of Capital Expenditure by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Capital Expenditures	$ 49,730	$ 32,779	$ 29,488
Ireland
Segment Reporting Information [Line Items]
Capital Expenditures	30,900	15,117	3,976
Rest Of Europe
Segment Reporting Information [Line Items]
Capital Expenditures	1,916	2,278	1,887
United States
Segment Reporting Information [Line Items]
Capital Expenditures	15,256	12,224	20,842
Other
Segment Reporting Information [Line Items]
Capital Expenditures	$ 1,658	$ 3,160	$ 2,783

Clients Representing Company's Net Revenue (Detail) - Customer Concentration Risk [Member] - Sales Revenue, Net	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Client A
Revenue, Major Customer [Line Items]
Clients which represented 10% or more of the company's net revenue	31.00%	31.00%	26.00%
Client B
Revenue, Major Customer [Line Items]
Clients which represented 10% or more of the company's net revenue			10.00%

Distribution of Interest Income by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Interest income	$ 1,306	$ 1,151	$ 986
Ireland
Segment Reporting Information [Line Items]
Interest income	102	284	355
Rest Of Europe
Segment Reporting Information [Line Items]
Interest income	1,151	798	501
United States
Segment Reporting Information [Line Items]
Interest income	4
Other
Segment Reporting Information [Line Items]
Interest income	$ 49	$ 69	$ 130

Distribution of Income Tax Charge by Geographical Area (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Segment Reporting Information [Line Items]
Provision for income taxes	$ 39,311	$ 30,248	$ 18,053
Ireland
Segment Reporting Information [Line Items]
Provision for income taxes	21,795	18,384	11,073
Rest Of Europe
Segment Reporting Information [Line Items]
Provision for income taxes	8,007	2,855	(7)
United States
Segment Reporting Information [Line Items]
Provision for income taxes	3,580	4,860	5,072
Other
Segment Reporting Information [Line Items]
Provision for income taxes	$ 5,929	$ 4,149	$ 1,915

Supplemental Disclosure of Cash Flow Information (Detail) - USD ($)
$ in Thousands

12 Months Ended

Dec. 31, 2015

Dec. 31, 2014

Dec. 31, 2013

Schedule of Cash Flow, Supplemental [Line Items]

Non-cash interest on acquisition consideration payable

^[1]

$ 240

Cash paid for interest

$ 2,175

$ 533

548

Cash paid for income taxes

$ 14,829

$ 17,829

$ 14,103

[1]	recorded within interest expense

Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Accumulated Other Comprehensive Income (Loss) [Line Items]
Currency translation adjustments	$ (57,315)	$ (22,210)
Currency impact on long term funding (Net of tax)	(5,484)	(9,252)
Actuarial loss on defined benefit pension plan (note 9)	(3,420)	(6,113)
Unrealized capital (loss)/gain - investments (note 3)	(34)	20
Realized gain on interest rate hedge	4,617
Total	$ (61,636)	$ (37,555)

- Definition

Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References + Details

Long-Term Debt - Senior Notes - Additional Information (Detail) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)
Debt Instrument [Line Items]
Long term debt	$ 350,000
Cash proceeds from interest rate hedge	$ 4,658
Interest rate hedge, maturity date	Nov. 17, 2015
Interest rate hedge, inception date	Oct. 05, 2015
Senior Notes
Debt Instrument [Line Items]
Long term debt	$ 350,000

- Definition

The carrying value as of the balance sheet date of the noncurrent portion of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

+ References + Details

Related Parties - Additional Information (Detail)	12 Months Ended
Related Parties - Additional Information (Detail)	Dec. 31, 2015 USD ($)	Dec. 31, 2015 EUR (€)	Dec. 31, 2014 USD ($)
Mr. Peter Gray
Related Party Transaction [Line Items]
Related party transaction amounts	$ 350,000	€ 265,000
Term of agreement	2 years	2 years
Related party agreement beginning date	Aug. 01, 2012	Aug. 01, 2012
Subsidiaries \| GW Pharmaceuticals Plc
Related Party Transaction [Line Items]
Revenue earned from related parties	$ 221,000
Subsidiaries \| Backlog Awards \| GW Pharmaceuticals Plc
Related Party Transaction [Line Items]
Due to related parties	88,000
Subsidiaries \| Dignity Sciences Limited
Related Party Transaction [Line Items]
Revenue earned from related parties	$ 100,000		$ 300,000