Accounting Policies [Abstract] Accounting Policies [Abstract] Accounts Payable Current Accounts payable Accounts Receivable Net Current Accounts receivable, net Accrued Bonuses Current Discretionary bonus Accrued Income Taxes Current Income taxes payable Accrued Income Taxes Noncurrent Non-current income taxes payable Accumulated Other Comprehensive Income Loss Net Of Tax Accumulated other comprehensive income Accumulated Other Comprehensive Income [Member] Accumulated Other Comprehensive Income 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 Sharebased Compensation Requisite Service Period Recognition Value Non-cash stock compensation expense Adjustments To Additional Paid In Capital Stock Issued Issuance Costs Share issuance costs Adjustments To Additional Paid In Capital Tax Effect From Share Based Compensation Tax benefit on exercise of options 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: Allocated Share Based Compensation Expense Share-based compensation Amendment Flag Amendment Flag Amortization Of Intangible Assets Amortization of intangibles 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 BeijingWits Medical Limited [Member] Beijing Wits Medical Limited [Member] BeijingWits Medical Limited Business Acquisition, Accrued Consideration Payable Business Acquisition Accrued Consideration Payable Additional consideration liability Business Acquisition Acquiree [Domain] Business Acquisition, Acquiree [Domain] Business Acquisition [Axis] Business Acquisition Business Acquisition Cost Of Acquired Entity Amount Held In Escrow Business Acquisition Cost Of Acquired Entity Amount Held In Escrow Amount held in escrow Business Acquisition [Line Items] Business Acquisition [Line Items] Business Acquisition Percentage Of Voting Interests Acquired Percentage of common stock acquired Business Acquisition, Purchase Price Allocation, Deferred Income Tax Liabilities Business Acquisition Purchase Price Allocation Deferred Income Tax Liabilities Deferred tax liability Business Acquisition Purchase Price Allocation Working Capital Business Acquisition Purchase Price Allocation Working Capital Working capital adjustment Business Combination Consideration Transferred 1 Amount of total consideration Business Combination Contingent Consideration Arrangements Cash Payment Made Business Combination Contingent Consideration Arrangements Cash Payment Made Further consideration paid in relation to certain performance milestones achieved Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability 1 Reduction in contingent consideration Business Combination Contingent Consideration Liability Additional consideration Contingent consideration Liabilities included in preliminary purchase price allocation re contingent consideration Business Combination Disclosure [Text Block] Business Combinations Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Cash And Equivalents Cash and cash equivalents Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Contingent Liability Liability arising from contingent consideration arrangement Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Assets Other Other current assets 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 Deferred Revenue Unbilled revenue Unbilled revenue Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Current Liabilities Other Current liabilities Other liabilities Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Intangibles Intangible asset Business Combination Recognized Identifiable Assets Acquired And Liabilities Assumed Property Plant And Equipment Property, plant and equipment Business Combination Recognized Identifiable Assets Acquired Goodwill And Liabilities Assumed Net Net assets acquired Net assets acquired Net assets acquired Net assets acquired Net assets acquired Business Combinations [Abstract] Business Combinations [Abstract] Noncurrent capital government grants, which are amortized and recognized in earnings over the grant period. Capital Government Grants Noncurrent Non-current government grants Capital Redemption Reserve Capital Redemption Reserve Capital redemption reserve Capital Redemption Reserve Capital Redemption Reserve [Member] Capital Redemption Reserve Cash Acquired From Acquisition Cash acquired with subsidiary undertakings 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 decrease in cash and cash equivalents Clinical trial services [Member] Clinical Trial Services [Member] Clinical Trial Services 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 Ordinary shares, shares issued Common Stock Shares Outstanding Ordinary shares, shares outstanding Common Stock Value Ordinary shares, par value 6 euro cents per share; 100,000,000 shares authorized, 60,861,741 shares issued and outstanding at June 30, 2013 and 60,287,498 shares issued and outstanding at December 31, 2012 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 Net Of Tax Total comprehensive income Comprehensive Income Net Of Tax [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 Current Fiscal Year End Date Current Fiscal Year End Date Customer Relationships [Member] Customer relationships acquired Deferred Income Tax Expense Benefit Deferred taxes Deferred Revenue Current Payments on account Deferred Tax Assets Net Current Deferred tax asset Deferred Tax Assets Net Noncurrent Non-current deferred tax asset Deferred Tax Liabilities Current Deferred tax liability Deferred Tax Liabilities Noncurrent Non-current deferred tax liability Depreciation Depreciation expense Depreciation And Amortization Depreciation and amortization Disclosure Of Compensation Related Costs Sharebased Payments [Abstract] Disclosure of Compensation Related Costs, Share-based Payments [Abstract] Document Document and Entity Information [Abstract] Document Document And Entity Information [Abstract] Document Documentand 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 Period End Date Document Period End Date Document Type Document Type 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 Total Compensation Cost Not Yet Recognized Non-cash stock compensation expense not yet recognized Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Period For Recognition 1 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 Twenty Zero Eight Plan [Member] Employee Stock Plan, 2008 Plan Employee Stock Plan, 2003 Plan [Member] Employee Stock Plan Twenty Zero Three Plan [Member] Employee Stock Plan, 2003 Plan Entities [Table] Entities [Table] Entity Central Index Key Entity Central Index Key Entity [Domain] Entity [Domain] Entity Registrant Name Entity Registrant Name Equity Component [Domain] Equity Component [Domain] Excess Tax Benefit From Share Based Compensation Financing Activities Tax benefit from the exercise of share options 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 First Quarter Twenty Eleven Restructuring Plan [Member] First Quarter Twenty Eleven Restructuring Plan [Member] 1st Quarter 2011 Restructuring Plan First Quarter Twenty Thirteen Restructuring Plan [Member] First Quarter Twenty Thirteen Restructuring Plan [Member] 1st Quarter 2013 Restructuring Plan Gain (Loss) On Contract Termination And Business Exit Costs Gain Loss On Contract Termination And Business Exit Costs Lease termination and exit costs Gain Loss On Sale 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 Goodwill Acquired Prior Period Good Will Acquired Prior Period Prior period acquisitions Goodwill And Intangible Assets Disclosure [Abstract] Goodwill and Intangible Assets Disclosure [Abstract] Goodwill Disclosure [Text Block] Goodwill Goodwill [Line Items] Goodwill [Line Items] Goodwill Translation Adjustments Foreign exchange movement I E Ireland Income Loss From Continuing Operations Before Income Taxes Minority Interest And Income Loss From Equity Method Investments 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 Income taxes receivable Income Taxes Receivable Noncurrent Non-current income taxes receivable Income Tax Expense Benefit Provision for income taxes Income Tax Expense (Benefit) Before Nonrecurring Charges Income Tax Expense Benefit Before Nonrecurring Charges Provision for income taxes before restructuring and other items Income Tax Expense (Benefit) For Nonrecurring Charges, Net Of Tax Income Tax Expense Benefit For Nonrecurring Charges Net Of Tax Provision for income taxes after restructuring and other items Income Tax Expense (Benefit) For Nonrecurring Charges, Tax Income Tax Expense Benefit For Nonrecurring Charges Tax Tax impact of restructuring and other items Increase Decrease In Accounts Payable Increase in accounts payable Increase Decrease In Accounts Receivable Increase in accounts receivable Increase Decrease In Accrued Income Taxes Payable (Decrease)/increase in income taxes payable Increase Decrease In Deferred Revenue Increase 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/(decrease) in other non-current liabilities Increase Decrease In Other Receivables (Increase) /decrease in other receivables Increase (Decrease) In Prepaid Expense And Other Current Assets Increase Decrease In Prepaid Expense And Other Current Assets (Increase)/decrease in prepayments and other current assets Increase Decrease In Restricted Cash Change in restricted cash, net Increase Decrease In Unbilled Receivables (Increase)/decrease in unbilled revenue Interest Expense Debt Interest expense Investment Income Interest Interest income Lease Termination and Asset Write Down Costs Lease Termination And Asset Write Down Costs Lease termination and asset write down costs Legal Entity [Axis] Legal Entity [Axis] Liabilities And Stockholders Equity Total Liabilities and Shareholders' Equity Liabilities And Stockholders Equity [Abstract] LIABILITIES AND SHAREHOLDERS' EQUITY Liabilities Current Total current liabilities Liabilities Current [Abstract] Current Liabilities: Liabilities Noncurrent [Abstract] Other Liabilities: Maximum [Member] Maximum Minimum [Member] Minimum Net Cash Provided By Used In Financing Activities Net cash provided by financing activities Net Cash Provided By Used In Financing Activities [Abstract] Cash flows from financing activities: Net Cash Provided By Used In Investing Activities Net cash used in investing activities Net Cash Provided By Used In Investing Activities [Abstract] Cash flows from investing activities: Net Cash Provided By Used In Operating Activities Net cash provided by operating activities Net Cash Provided By Used In Operating Activities [Abstract] Cash flows from operating activities: Net Income Loss Net income Net income Noncompete Agreements [Member] Non-compete Agreements Nontrade Receivables Current Other receivables Number of Employees Number Of Employees Addition of new employees Office Consolidations [Member] Office Consolidations [Member] Office Consolidations 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 Operating Income Loss Before Restructuring Charges Operating Income Loss Before Restructuring Charges Income from operations, excluding Restructuring and other items 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 Foreign Currency Transaction And Translation Adjustment Net Of Tax Currency translation adjustment Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax Unrealized capital gain - investments Other Countries [Member] Other Countries [Member] Rest of World Other Liabilities Current Other liabilities Other Liabilities Noncurrent Non-current other liabilities Other Restructuring Costs Other non-recurring items Resource rationalizations Payments For Repurchase Of Common Stock Repurchase of ordinary shares Payments For Restructuring Cash payments Payments for Share Repurchase Costs Payments For Share Repurchase Costs Share repurchase costs Payments Of Stock Issuance Costs Share issuance costs Payments To Acquire Businesses Gross Cash consideration Purchase of subsidiary undertakings Payments To Acquire Property Plant And Equipment Purchase of property, plant and equipment Payments To Acquire Short Term Investments Purchase of short term investments Percentage of Fair Market Value Percentage Of Fair Market Value Percentage of option price for fair value of ordinary share Performance Share Unit [Member] Performance Share Unit [Member] Performance Share Unit (PSUs) Plan Name [Axis] Plan Name Plan Name [Domain] Plan Name [Domain] Preliminary Fair Values of Assets Acquired and Liabilities Assumed Related to Acquisition. Preliminary Fair Values Of Assets Acquired And Liabilities Assumed Related To Acquisition [Text Block] Estimates of Fair Values of Assets Acquired and Liabilities Assumed Prepaid Expense And Other Assets Current Prepayments and other current assets PriceSpective Llc [Member] Price Spective Llc [Member] PriceSpective LLC Proceeds From Lines Of Credit Drawdown of bank credit lines and loan facilities Proceeds From Sale Of Short Term Investments Sale of short term investments Proceeds From Stock Options Exercised Proceeds from exercise of share options Property, Plant and Equipment by Geography. Property Plant And Equipment By Geography Table [Text Block] Distribution of Property, Plant and Equipment, Net, by Geographical Area Property Plant And Equipment Net Property, plant and equipment, net Range [Axis] Range Range [Member] Range [Domain] 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 grants Repayments Of Lines Of Credit Repayment of bank credit lines and loan facilities Rest Of Europe [Member] Rest Of Europe [Member] Rest Of Europe Restricted Cash And Cash Equivalents At Carrying Value Restricted cash Restricted Stock Units And Performance Stock Unit Awards [Member] Restricted Stock Units And Performance Stock Unit Awards [Member] Restricted Stock Units And Performance Stock Units 2013 Restricted Stock Units R S U [Member] Restricted Stock Units (RSUs) Restricted Stock Units Twenty Zero Eight [Member] Restricted Stock Units Twenty Zero Eight [Member] Restricted Stock Units 2008 Restructuring And Other Charges [Member] Restructuring And Other Charges [Member] Restructuring And Other Charges Restructuring And Related Activities [Abstract] Restructuring and Related Activities [Abstract] Restructuring And Related Activities Disclosure [Text Block] Restructuring and Other Items Amount charged against earnings in the period for incurred and estimated costs associated with exit from or disposal of business activities or restructurings pursuant to a duly authorized plan, excluding asset retirement obligations net of research and development incentives. Restructuring Charge Net Restructuring and other items Total Restructuring Charges Initial provision recognized Restructuring charges Restructuring Charges. Restructuring Charges Table [Text Block] Recognized Restructuring and Other Items Restructuring Cost And Reserve [Axis] Restructuring Type Restructuring Cost And Reserve [Line Items] Restructuring Cost and Reserve [Line Items] Restructuring Fiscal Twenty Twelve Plan [Member] Restructuring Fiscal Twenty Twelve Plan [Member] Restructuring - Fiscal 2012 Plan Restructuring Plan [Axis] Restructuring Plan Restructuring Plan [Domain] Restructuring Plan [Domain] Restructuring Reserve Provision balance at end of period Restructuring Reserve Translation Adjustment Foreign exchange movement Restructuring, Settlement and Other Charges Restructuring Settlement And Other Charges Agreement settlement charges 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 Net Revenue Revenues [Abstract] Revenue: Sales Revenue Net 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 Tax Expense (Benefit) 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 Intangible Assets And Goodwill Table [Text Block] Goodwill Schedule of Non Cash Stock Compensation Expense. Schedule Of Non Cash Stock Compensation Expense Table [Text Block] Non-Cash Stock Compensation Expense Schedule Of Nonvested Share Activity Table [Text Block] Summary of Movement in Non-Vested Share Options Schedule Of Restructuring And Related Costs [Table] Schedule of Restructuring and Related Costs [Table] Schedule Of Restructuring And Related Costs [Text Block] Prior Period Restructuring Charges Schedule Of Restructuring Reserve By Type Of Cost [Text Block] Details of Movement in Restructuring Provisions Recognized Schedule Of Segment Reporting Information By Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Schedule Of Share Based Compensation Activity Table [Text Block] Summary of RSU Activity 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 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 Total Assets By Geographic Area. Schedule Of Total Assets By Geographic Area Table [Text Block] Distribution of Total Assets by Geographical Area 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] Second Quarter Twenty Thirteen Restructuring Plan [Member] Second Quarter Twenty Thirteen Restructuring Plan [Member] 2nd Quarter 2013 Restructuring Plan Segment Geographical [Domain] Geographical [Domain] Segment Reporting [Abstract] Segment Reporting [Abstract] Segment Reporting Disclosure [Line Items] Segment Reporting Disclosure [Line Items] Segment Reporting Disclosure [Line Items] Segment Reporting Disclosure [Table] Segment Reporting Disclosure [Table] Segment Reporting Disclosure [Table] 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 Expense Share Based Compensation Share compensation expense Share-based compensation expense Share Based Compensation Arrangement By Share Based Payment Award Award Vesting Period 1 Shares vesting period Share Based Compensation Arrangement by Share Based Payment Award, Equity Instruments Other than Options, Cancelled and Forfeited in Period, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Cancelled And Forfeited In Period Weighted Average Grant Date Fair Value Forfeited 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 Grants In Period 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 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 Rollforward [Abstract] Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Rollforward [Abstract] Options Outstanding Number of Shares Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Vested and Unvested, Number Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Unvested 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, Vested and Unvested, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested And Unvested 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 Vested In Period Shares vested Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Vested In Period Total 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, Equity Instruments Other than Options, Weighted Average Grant Date Fair Value [Abstract] Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Weighted Average Grant Date Fair Value [Abstract] Weighted Average Fair Value Sharebased Compensation Arrangement By Sharebased 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 Sharebased Compensation Arrangement By Sharebased Payment Award Fair Value Assumptions Expected Term 1 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, Granted in Period, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Granted In Period Weighted Average Grant Date Fair Value Granted Share based Compensation Arrangement by Share based Payment Award, Nonvested Options, Grants in Period Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Grants In Period 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, Number Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Outstanding Number Ending Balance Beginning Balance 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 Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Vested In Period Vested 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, Nonvested Options, Vested in Period, Weighted Average Grant Date Fair Value Share Based Compensation Arrangement By Share Based Payment Award Nonvested Options Vested In Period Weighted Average Grant Date Fair Value Vested Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized Ordinary shares which have been reserved for issuance Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value 1 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 Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Weighted Average Remaining Contractual Term 1 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 Total 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 Granted Share based Compensation Arrangement by Share based Payment Award, Options, Grants in Period, Fair Value Share Based Compensation Arrangement By Share Based Payment Award Options Grants In Period Fair Value Options granted fair value 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 Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Number Of Shares [Roll Forward] Number of Shares Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Number Of Shares Forfeited Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Options Forfeited Weighted Average Grant Date Fair Value Forfeited Sharebased Compensation Arrangement By Sharebased Payment Award Options Nonvested Weighted Average Grant Date Fair Value Ending Balance Beginning Balance Sharebased Compensation Arrangement By Sharebased 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 [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 Sharebased Compensation Arrangement By Sharebased Payment Award Options Outstanding Weighted Average Remaining Contractual Term 2 Outstanding at end of period Weighted Average Remaining Contractual Life of Options Outstanding Share Based Compensation Arrangement By Share Based Payment Award Options Vested And Expected To Vest Outstanding Number Number of shares expected to vest Share-based Compensation Arrangement by Share-based Payment Award, Options, Weighted Average Exercise Price [Abstract] Share Based Compensation Arrangement By Share Based Payment Award Options Weighted Average Exercise Price [Abstract] Weighted Average Exercise Price 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] Sharebased Compensation Arrangement By Sharebased 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, Other than Options, Weighted Average Remaining Contractual Term [Abstract] Share Based Compensation Arrangement By Share Based Payment Award Other Than Options Weighted Average Remaining Contractual Term [Abstract] Weighted Average Remaining Contractual Life 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 Arrangements By Share Based Payment Award Award Type And Plan Name [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-based Compensation Arrangements by Share-based Payment Award. Share Based Compensation Arrangements By Share Based Payment Award [Text Block] Share-based Awards Shares Issued Balance (in shares) Balance (in shares) 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] Statement Equity Components [Axis] Equity Components [Axis] Statement 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 Balance Balance Total Shareholders' Equity Stockholders Equity [Abstract] Shareholders' Equity: Stock Issued During Period Shares Restricted Stock Award Net Of Forfeitures Issue of restricted share units (in shares) Stock Issued During Period Shares Stock Options Exercised Exercise of share options (in shares) Exercised Stock Issued During Period Value Restricted Stock Award Net Of Forfeitures Issue of restricted share units Stock Issued During Period Value Stock Options Exercised Exercise of share options Text Block [Abstract] Text Block [Abstract] Trading Symbol Trading Symbol Twenty Twelve Restructuring Plan [Member] Twenty Twelve Restructuring Plan [Member] 2012 Restructuring Plan 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 U S U.S. Weighted Average Number Diluted Shares Outstanding Adjustment Effect of dilutive share options outstanding Weighted Average Number Of Diluted Shares Outstanding Diluted Weighted average number of ordinary shares for diluted net income per ordinary share Weighted Average Number Of Shares Outstanding [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