Accounting Policies [Abstract] Accounting Policies [Abstract] Accounts Payable, Current Accounts payable Accounts Receivable, Net, Current Accounts receivable, net Accrued Income Taxes, Current Income taxes payable Accrued Income Taxes, Noncurrent Non-current income taxes payable Accrued Interest On Short Term Bank Deposits Accrued Interest On Short Term Bank Deposits Interest on short term investments Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated other comprehensive income AOCI Attributable to Parent [Member] Accumulated Other Comprehensive Income (Loss) Additional Paid in Capital, Common Stock Additional paid-in capital Additional Paid-in Capital [Member] Additional Paid-in Capital Adjustments to Additional Paid in Capital, Share-based Compensation, Requisite Service Period Recognition Non-cash stock compensation expense Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs Share issuance costs Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Retained Earning Share Repurchase costs Adjustment to Retained Earning Share Repurchase costs Share repurchase costs Amendment Flag Amendment Flag Amortization of Debt Issuance Costs Amortization of financing costs Amortization Of Gain On Interest Rate Hedge Amortization Of Gain On Interest Rate Hedge Amortization of gain on interest rate hedge Amortization of Intangible Assets Amortization of intangibles Asset Impairment [Member] Asset Impairment [Member] Asset Impairment Assets Assets Total Assets Assets [Abstract] ASSETS Assets, Current Total current assets Assets, Current [Abstract] Current Assets: Assets, Noncurrent [Abstract] Other Assets: Available-for-sale Securities, Debt Securities, Current Short term investments - available for sale Award Type [Axis] Award Type Balance Sheet Location [Axis] Balance Sheet Location [Axis] Balance Sheet Location [Domain] Balance Sheet Location [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition [Axis] Business Acquisition Business Acquisition [Line Items] Business Acquisition [Line Items] Additional payments made in respect of working capital review of net assets at acquisition. Business Acquisition Purchase Price Allocation Adjustment To Working Capital Working capital adjustment Working capital adjustment Business Combination, Consideration Transferred Cash consideration Cash outflows (including other liabilities assumed of $9.2 million) Business Combination, Consideration Transferred, Gross Business Combination, Consideration Transferred, Gross Gross cash outflows Business Combination, Consideration Transferred, Liabilities Incurred Other liabilities assumed Business Combination, Contingent Consideration Arrangements, Range of Outcomes, Value, High Maximum additional consideration that might be payable Business Combination, Contingent Consideration, Liability Contingent consideration Fair Value of the deferred consideration on acquisition Business Combination Disclosure [Text Block] Business Combinations Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Consideration Transferred Cash consideration, net of working capital adjustment Represents final adjustment (as defined) to other liabilities acquired in connection with a business combination. Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current Liabilities, Other Fair value adjustment to other liabilities Represents final adjustment (as defined) to deferred tax liabilities acquired in connection with a business combination. Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Deferred Tax Liabilities Fair value adjustment to deferred tax liability Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles Fair value adjustment to intangible assets Represents final adjustment (as defined) to accounts receivable acquired in connection with a business combination. Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Receivables Fair value adjustment to accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents Cash Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets Prepayments and other current assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables Accounts receivable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Accounts Payable Accounts payable Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other Other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities, Current Deferred tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deferred Tax Liabilities Noncurrent Non-current deferred tax liability Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles Intangible asset Intangible assets Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other Non-current other liabilities Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Payments on Account Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Payments on Account Payments on account Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment Property, plant and equipment Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Unbilled Revenue Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Unbilled Revenue Unbilled revenue Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net Net assets acquired Business Combinations [Abstract] Business Combinations [Abstract] Buyback Program [Member] Buyback Program [Member] Buyback Program Noncurrent capital government grants, which are amortized and recognized in earnings over the grant period. Capital Government Grants Noncurrent Non-current government grants Cash and Cash Equivalents, at Carrying Value Cash and cash equivalents at end of period Cash and cash equivalents at beginning of period Cash and cash equivalents Cash and Cash Equivalents, Period Increase (Decrease) Net increase in cash and cash equivalents Class of Treasury Stock [Table] Class of Treasury Stock [Table] Clinical Research Management Inc. [Member] Clinical Research Management, Inc. [Member] Clinical Research Management Inc. Commitments and Contingencies Commitments and contingencies Common Stock [Member] Ordinary Shares Common Stock, Par or Stated Value Per Share Ordinary shares, par value Common Stock, Shares Authorized Ordinary shares, shares authorized Common Stock, Shares, Issued Balance (in shares) Balance (in shares) Ordinary shares, shares issued Common Stock, Shares, Outstanding Ordinary shares, shares outstanding Common Stock, Value, Issued Ordinary shares, par value 6 euro cents per share; 100,000,000 shares authorized, 53,775,703 shares issued and outstanding at March 31, 2017 and 54,530,843 shares issued and outstanding at December 31, 2016 Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Line Items] Compensation Related Costs Share Based Payments Disclosure [Table] Compensation Related Costs Share Based Payments Disclosure [Table] Compensation Related Costs Share Based Payments Disclosure [Table] Comprehensive Income (Loss), Net of Tax, Attributable to Parent Total comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Comprehensive income: Contracts Revenue Gross revenue Cost of Goods and Services Sold Direct costs Cost of Reimbursable Expense Reimbursable expenses Cost of Revenue [Abstract] Costs and expenses: Cost of Sales [Member] Direct costs Costs and Expenses Total costs and expenses Cumulative Effect of New Accounting Principle in Period of Adoption Cumulative effect adjustment from adoption of ASU 2016-09 Current Fiscal Year End Date Current Fiscal Year End Date Customer Lists and Order or Production Backlog [Member] Customer Lists and Order or Production Backlog [Member] Customer list and order backlog Customer Lists [Member] Customer Lists Deferred Income Taxes and Tax Credits Deferred taxes Deferred Revenue, Current Payments on account Deferred Tax Assets, Net of Valuation Allowance, Noncurrent Non-current deferred tax asset Deferred Tax Liabilities, Net, Noncurrent Non-current deferred tax liability Depreciation Depreciation expense Depreciation, Depletion and Amortization, Nonproduction Depreciation and amortization Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Disclosure of Compensation Related Costs, Share-based Payments [Text Block] Share-based Awards Document And Entity Information [Abstract] Document And Entity Information [Abstract] Document And Entity Information [Abstract] Document Fiscal Period Focus Document Fiscal Period Focus Document Fiscal Year Focus Document Fiscal Year Focus Document Information [Line Items] Document Information [Line Items] Document Information [Table] Document Information [Table] Document Period End Date Document Period End Date Document Type Document Type Earliest Tax Year [Member] Earliest Tax Year Earnings Per Share [Abstract] Net income per Ordinary Share: Earnings Per Share, Basic Basic Earnings Per Share, Diluted Diluted Earnings Per Share [Text Block] Net income per ordinary share Effect of Exchange Rate on Cash and Cash Equivalents Effect of exchange rate movements on cash Employee [Member] Employee [Member] Individual Employee Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized Non-cash stock compensation expense not yet recognized Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition Unrecognized stock-based compensation expense, weighted average period (years) Employee Stock Option [Member] Employee Stock Option Employee Stock Plan, 2008 Plan [Member] Employee Stock Plan, 2008 Plan [Member] Employee Stock Plan, 2008 Plan Employee Stock Plan, 2003 Plan [Member] Employee Stock Plan, 2003 Plan [Member] Employee Stock Plan, 2003 Plan Entity Central Index Key Entity Central Index Key Entity [Domain] Entity [Domain] Entity Registrant Name Entity Registrant Name Equity [Abstract] Equity [Abstract] Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Equity Component [Domain] Equity Component [Domain] Excess Tax Benefit from Share-based Compensation, Financing Activities Excess tax benefit on exercise of equity compensation Facility Closing [Member] Manchester, United Kingdom facility closure Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Major Class Name [Domain] Finite-Lived Intangible Assets, Net Intangible assets Gain (Loss) on Disposition of Property Plant Equipment Loss on disposal of property, plant and equipment Goodwill Closing balance Opening balance Goodwill Goodwill, Acquired During Period Current period acquisitions (Note 3) Goodwill and Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill Disclosure [Text Block] Goodwill Goodwill, Foreign Currency Translation Gain (Loss) Foreign exchange movement Goodwill [Line Items] Goodwill [Line Items] Goodwill, Purchase Accounting Adjustments Prior period acquisitions (Note 3) IRELAND Ireland Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Income before provision for income taxes Income Statement [Abstract] Income Statement [Abstract] Income Statement Location [Axis] Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs, by Report Line Income Statement Location [Domain] Income Statement Location [Domain] Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Income Tax Disclosure [Text Block] Income Taxes Income Taxes Receivable, Current Income taxes receivable Income Taxes Receivable, Noncurrent Non-current income taxes receivable Income Tax Expense (Benefit) Provision for income taxes Provision for income taxes Increase (Decrease) in Accounts Payable Increase/(decrease) in accounts payable Increase (Decrease) in Accounts Receivable Decrease in accounts receivable Increase (Decrease) in Income Taxes Payable Increase in income taxes payable Increase (Decrease) in Deferred Revenue Decrease in payments on account Increase (Decrease) in Operating Capital [Abstract] Changes in assets and liabilities: Increase (Decrease) in Other Current Liabilities Increase/(decrease) in other current liabilities Increase (Decrease) in Other Noncurrent Assets Increase in other non-current assets Increase (Decrease) in Other Noncurrent Liabilities Increase in other non-current liabilities Increase (Decrease) in Other Receivables Increase in other receivables Increase (Decrease) in Prepaid Expense and Other Assets (Increase)/decrease in prepayments and other current assets Increase (Decrease) in Unbilled Receivables Increase in unbilled revenue Interest Expense, Debt Interest expense Investment Income, Interest Interest income Latest Tax Year [Member] Latest Tax Year Legal Entity [Axis] Legal Entity [Axis] Liabilities Total Liabilities Liabilities and Equity Total Liabilities and Shareholders' Equity Liabilities and Equity [Abstract] LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities, Current Total current liabilities Liabilities, Current [Abstract] Current Liabilities: Liabilities, Noncurrent [Abstract] Other Liabilities: Long-lived Assets by Geographic Areas [Table Text Block] Distribution of Property, Plant and Equipment, Net, by Geographical Area Long-term Line of Credit, Noncurrent Non-current bank credit lines and loan facilities Maximum [Member] Maximum Media Pharma Solutions [Member] Media Pharma Solutions [Member] MediMedia Pharma Solutions Minimum [Member] Minimum Net Cash Provided by (Used in) Financing Activities, Continuing Operations Net cash provided by financing activities Net Cash Provided by (Used in) Financing Activities, Continuing Operations [Abstract] Cash flows from financing activities: Net Cash Provided by (Used in) Investing Activities, Continuing Operations Net cash used in investing activities Net Cash Provided by (Used in) Investing Activities, Continuing Operations [Abstract] Cash flows from investing activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations Net cash provided by operating activities Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Cash flows from operating activities: Net Income (Loss) Attributable to Parent Net income Net income Nontrade Receivables, Current Other receivables Number of Clinical Research Sites Acquired Number of Clinical Research Sites Acquired Number of clinical research sites acquired Number of Operating Segments Number of operating segments Number of Patients Number of Patients Number of active patients via electronic medical records acquired Onerous Lease [Member] Onerous Lease [Member] Onerous Lease Open Tax Year Tax year subject to examination by major tax jurisdictions Operating Income by Geography. Operating Income by Geography [Table Text Block] Distribution of Income from Operations by Geographical Area Operating Income (Loss) Income from operations Income from operations Order or Production Backlog [Member] Order Backlog Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Basis of Presentation Other Assets, Noncurrent Non-current other assets Adjustment that results from the process of translating the impact of long-term funding into the functional currency of the reporting entity. Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment, Before Tax, Long Term Funding Currency impact of long term funding Tax impact on the adjustment that results from the process of translating the impact of long-term funding into the functional currency of the reporting entity. Other Comprehensive Income Foreign Currency Transaction And Translation Adjustment Long Term Funding Tax Tax on currency impact of long term funding Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Amortization of interest rate hedge Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax Currency translation adjustment Other Comprehensive Income (Loss), Unrealized Holding Gain (Loss) on Securities Arising During Period, Net of Tax Unrealized capital gain - investments Other Current Liabilities [Member] Other liabilities Other Liabilities, Current Other liabilities Other Liabilities, Noncurrent Non-current other liabilities Other Noncurrent Liabilities [Member] Non-current other liabilities Other undenominated capital. Other Undenominated Capital Other undenominated capital Other undenominated capital. Other Undenominated Capital [Member] Other Undenominated Capital Payments for Repurchase of Common Stock Repurchase of ordinary shares Payments for Share Repurchase Costs Payments for Share Repurchase Costs Share repurchase costs Payments of Stock Issuance Costs Share issue costs Payments to Acquire Businesses, Gross Total cash outflows Payments to Acquire Businesses, Net of Cash Acquired Net cash outflow Net cash outflows Payments to Acquire Property, Plant, and Equipment Purchase of property, plant and equipment Payments to Acquire Short-term Investments Purchase of short term investments Performance Based Grants [Member] Performance Based Grants [Member] PSUs Based on Service and EPS Targets Performance Share Unit [Member] Performance Share Unit [Member] Performance Share Unit (PSUs) Plan Name [Axis] Plan Name Plan Name [Domain] Plan Name [Domain] PMG Research Incorporated [Member] PMG Research Incorporated [Member] PMG Prepaid Expense and Other Assets, Current Prepayments and other current assets Proceeds from Sale of Short-term Investments Sale of short term investments Proceeds from Stock Options Exercised Proceeds from exercise of equity compensation Property, Plant and Equipment, Net Property, plant and equipment, net Range [Axis] Range Range [Domain] Range [Domain] Reconciliation of Assets from Segment to Consolidated [Table Text Block] Distribution of Total Assets by Geographical Area Reconciliation of Provision of Income Taxes [Line Items] Reconciliation of Provision of Income Taxes [Line Items] Reconciliation of Provision of Income Taxes [Line Items] Reconciliation of Provision of Income Taxes [Table] Reconciliation of Provision of Income Taxes [Table] Reconciliation of Provision of Income Taxes [Table] Amortization of Government Grants. Recovery of Amortization of Government Grants Amortization of government grants Resource Rationalizations [Member] Resource Rationalizations [Member] Resource Rationalizations Rest Of Europe [Member] Rest Of Europe [Member] Rest Of Europe Rest of World [Member] Rest of World [Member] Rest of World Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) Restricted Stock Units Twenty Thirteen [Member] Restricted Stock Units Twenty Thirteen [Member] Restricted Stock Units 2013 Restricted Stock Units Twenty Zero Eight [Member] Restricted Stock Units Twenty Zero Eight [Member] Restricted Stock Units 2008 Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Restructuring and Related Activities Disclosure [Text Block] Restructuring Restructuring Charges Restructuring charges Total provision recognized Restructuring Type [Axis] Restructuring Type Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring Plan [Axis] Restructuring Plan Restructuring Plan [Domain] Restructuring Plan [Domain] Restructuring Program [Axis] Restructuring Program [Axis] Restructuring Program [Axis] Restructuring Program [Domain] Restructuring Program [Domain] Restructuring Program [Domain] Restructuring Reserve Closing provision Restructuring Reserve, Accrual Adjustment Related to Asset Write-off Restructuring Reserve, Accrual Adjustment Related to Asset Write-off Asset write-off Restructuring Reserve, Current Restructuring Reserve,current Restructuring Reserve, Noncurrent Restructuring Reserve, Noncurrent Restructuring Reserve, Foreign Currency Translation Gain (Loss) Foreign exchange Restructuring Reserve Utilizations Restructuring Reserve Utilizations Utilized Retained Earnings (Accumulated Deficit) Retained earnings Retained Earnings [Member] Retained Earnings Revenue from External Customers by Geographic Areas [Table Text Block] Distribution of Net Revenue by Geographical Area Revenues [Abstract] Revenue: Revenue, Net Net Revenue Net revenue Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Income Taxes Recognized During Period Schedule Of Depreciation And Amortization Expense By Geographical Area. Schedule Of Depreciation And Amortization Expense By Geographical Area [Table Text Block] Distribution of Depreciation and Amortization by Geographical Area Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Reconciliation of Number of Shares Used in Computation of Basic and Diluted Net Income Per Ordinary Share Schedule of Goodwill [Table] Schedule of Goodwill [Table] Schedule of Goodwill [Table Text Block] Goodwill Schedule of Non Cash Stock Compensation Expense. Schedule of Non Cash Stock Compensation Expense [Table Text Block] Schedule of Non-cash Stock Compensation Expense Schedule of Nonvested Share Activity [Table Text Block] Summary of Movement in Non-Vested Share Options Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block] Summary of Estimates of Fair Values of Assets Acquired and Liabilities Assumed Schedule of Restructuring and Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Restructuring and Related Costs [Table Text Block] Restructuring Charges Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule Of Share Based Compensation Restricted Stock Units Performance Stock Units Award Activity [Table Text Block] Schedule Of Share Based Compensation Restricted Stock Units Performance Stock Units Award Activity [Table Text Block] RSU and PSU Activity Schedule of Share-based Compensation, Stock Options, Activity [Table Text Block] Summary of Stock Option Activity Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Table Text Block] Weighted Average Fair Values and Assumptions Used Schedule of Weighted Average Number of Diluted Shares Outstanding [Line Items] Schedule of Weighted Average Number of Diluted Shares Outstanding [Line Items] Schedule of Weighted Average Number of Diluted Shares Outstanding [Line Items] Schedule of Weighted Average Number of Diluted Shares Outstanding [Table] Schedule of Weighted Average Number of Diluted Shares Outstanding [Table] Schedule of Weighted Average Number of Diluted Shares Outstanding [Table] Geographical [Domain] Geographical [Domain] Segment Reporting [Abstract] Segment Reporting [Abstract] Segment Reporting Disclosure [Text Block] Business Segment Information Segment Reporting Information [Line Items] Segment Reporting Information [Line Items] Selling, General and Administrative Expense Selling, general and administrative expense Selling, General and Administrative Expenses [Member] Selling, general and administrative Share-based Compensation Share-based compensation expense Stock compensation expense Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period Shares vesting period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Additional Disclosures [Abstract] Weighted Average Remaining Contractual Life Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeited in Period Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Forfeitures, Weighted Average Grant Date Fair Value Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period Granted Stock units granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value Granted Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Outstanding at ending of period Outstanding at beginning of period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward] Outstanding Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value Outstanding at end of period Outstanding at beginning of period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Weighted Average Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Outstanding, Weighted Average Remaining Contractual Terms Outstanding at end of period Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period Shares vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Fair Value Fair value of stock units vested Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date Fair Value Shares vested Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period Shares expiration period Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions and Methodology [Abstract] Assumptions: Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Dividend Rate Dividend yield Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Term Expected life Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Expected Volatility Rate Expected volatility Share-based Compensation Arrangement by Share-based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Risk-free interest rate Share Based Compensation Arrangement by Share Based Payment Award, Forfeited in Period, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement by Share Based Payment Award, Forfeited in Period, Weighted Average Grant Date Fair Value Forfeited Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share-based Compensation Arrangement by Share-based Payment Award [Line Items] Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Forfeited in Period Weighted Average Exercise Price Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Forfeited in Period Weighted Average Exercise Price Forfeited Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Granted in Period Weighted Average Exercise Price Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Granted in Period Weighted Average Exercise Price Granted Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Outstanding Exercise Price Abstract Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Outstanding Exercise Price Abstract Weighted Average Exercise Price Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Outstanding Weighted Average Exercise Price Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Outstanding Weighted Average Exercise Price Ending balance Beginning balance Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Vested in Period Weighted Average Exercise Price Share Based Compensation Arrangement by Share Based Payment Award, Nonvested Options, Vested in Period Weighted Average Exercise Price Vested Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized Additional number of ordinary shares which have been reserved for issuance Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized Ordinary shares which have been reserved for issuance Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant Stock units to be granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value Fully vested total intrinsic value Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Number Exercisable - number of shares Exercisable at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Exercise Price Exercisable - weighted average exercise price Exercisable at end of period Share Based Compensation Arrangement by Share Based Payment Award, Options, Exercisable, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement by Share Based Payment Award, Options, Exercisable, Weighted Average Grant Date Fair Value Exercisable at end of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term Exercisable - weighted average remaining contractual life Exercisable at end of period Share Based Compensation Arrangement By Share Based Payment Award Options Exercised In Period Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Options Exercised In Period Weighted Average Grant Date Fair Value Exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value Intrinsic value of option exercised Share-based Compensation Arrangement by Share-based Payment Award, Options, Forfeitures in Period Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross Granted Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Granted Weighted average fair value Share Based Compensation Arrangement by Share Based Payment Award, Options, Grants in Period, Weighted Average Option Price Share Based Compensation Arrangement by Share Based Payment Award, Options, Grants in Period, Weighted Average Option Price Weighted average fair value per option Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares Ending Balance Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Number of Shares [Roll Forward] Options Outstanding Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Weighted Average Grant Date Fair Value Forfeited Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value Ending Balance Beginning Balance Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Weighted Average Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Number Outstanding at end of period Outstanding at beginning of period Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Option Price Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Option Price Options outstanding fair value Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward] Options Outstanding Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price Outstanding at end of period Outstanding at beginning of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Abstract] Weighted Average Exercise Price Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Remaining Contractual Term Outstanding at end of period Weighted average contractual term of options outstanding Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Number of Shares Vested Share-based Compensation Arrangement by Share-based Payment Award, Options, Vested, Weighted Average Grant Date Fair Value Vested Share Based Compensation Arrangement by Share Based Payment Award, Options, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement by Share Based Payment Award, Options, Weighted Average Grant Date Fair Value Outstanding at end of period Outstanding at beginning of period Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Grant Date Fair Value [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Grant Date Fair Value [Abstract] Weighted Average Fair Value Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Term [Abstract] Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Remaining Contractual Term [Abstract] Weighted Average Remaining Contractual Life Share Based Compensation Arrangement by Share Based Payment Award Other Than Options Expected Vesting Period Share Based Compensation Arrangement by Share Based Payment Award Other Than Options Expected Vesting Period Cumulative EPS vesting period Share-based Compensation Arrangement by Share-based Payment Award, Percentage of Outstanding Stock Maximum Maximum number of award as percentage of shares outstanding Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent Percentage of option price for fair value of ordinary share Equity Award [Domain] Equity Award [Domain] Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price Exercised Share-based Compensation Arrangements by Share-based Payment Award, Options, Forfeitures in Period, Weighted Average Exercise Price Forfeited Share-based Compensation Arrangements by Share-based Payment Award, Options, Grants in Period, Weighted Average Exercise Price Granted Share Repurchase Program [Axis] Share Repurchase Program Share Repurchase Program [Domain] Share Repurchase Program [Domain] Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Line Items] Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table] Significant Change in Unrecognized Tax Benefits is Reasonably Possible [Table] Equity Components [Axis] Equity Components [Axis] Geographical [Axis] Geographical Statement [Line Items] Statement [Line Items] Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Statement [Table] Statement [Table] Stockholders' Equity Attributable to Parent Balance Balance Total Shareholders' Equity Stockholders' Equity Attributable to Parent [Abstract] Shareholders' Equity: Stockholders' Equity Note Disclosure [Text Block] Share Capital Stock Issued During Period, Shares, Share-based Compensation, Net of Forfeitures Issue of restricted share units (in shares) Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period Exercise of share options (in shares) Exercised Stock Issued During Period, Value, Share-based Compensation, Net of Forfeitures Issue of restricted share units Stock Issued During Period, Value, Stock Options Exercised Exercise of share options Stock Repurchased and Retired During Period, Shares Share repurchase program (in shares) Stock Repurchased and Retired During Period, Value Share repurchase program Stock Repurchase Program, Authorized Amount Stock repurchase program, authorized amount Stock Repurchase Program Authorized Percentage Stock Repurchase Program Authorized Percentage Share repurchase program, authorized percentage Subsequent Events [Abstract] Subsequent Events [Abstract] Tax Period [Axis] Tax Period [Axis] Tax Period [Domain] Tax Period [Domain] Trading Symbol Trading Symbol Treasury Stock, Shares, Acquired Ordinary shares repurchased Treasury Stock, Value, Acquired, Cost Method Ordinary shares repurchased, value Type of Restructuring [Domain] Type of Restructuring [Domain] Unbilled Contracts Receivable Unbilled revenue Unrecognized Tax Benefits Liability for unrecognized tax benefit Unrecognized Tax Benefits, Current Year Tax Positions Unrecognized Tax Benefits, Current Year Tax Positions Items generating unrecognized tax benefits Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Interest and related penalties UNITED STATES United States Weighted Average Number Diluted Shares Outstanding Adjustment Effect of dilutive share options outstanding Weighted Average Number of Shares Outstanding, Diluted Diluted Weighted average number of ordinary shares outstanding for diluted net income per ordinary share Weighted Average Number of Shares Outstanding, Diluted [Abstract] Weighted average number of Ordinary Shares outstanding: Weighted Average Number of Shares Outstanding, Basic Basic Weighted average number of ordinary shares outstanding for basic net income per ordinary share Workforce Reduction [Member] Workforce Reduction [Member] Workforce Reduction