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Compensation Related Costs Share Based Payments Disclosure [Line Items] Cash and cash equivalents Cash and Cash Equivalents, at Carrying Value Weighted average discount rate Operating Lease, Weighted Average Discount Rate, Percent Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activities Credit Facility [Domain] Credit Facility [Domain] Share repurchase program (in shares) Share repurchase program, number of shares repurchased (in shares) Stock Repurchased and Retired During Period, Shares Business Combinations Business Combinations Policy [Policy Text Block] Basis spread on variable rate (in percent) Debt Instrument, Basis Spread on Variable Rate Total long-term debt, net Long-Term Debt, Excluding Current Maturities Goodwill Goodwill Disclosure [Text Block] Buyback Program Buyback Program [Member] Buyback Program [Member] Diluted (in shares) Weighted average number of ordinary shares outstanding for diluted net income per ordinary share (in shares) Weighted Average Number of Shares Outstanding, Diluted Schedule of accounts receivables and unbilled revenue, and unbilled services and unearned revenue Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Ordinary shares which have been reserved for issuance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Additional Shares Authorized Revenue Accounts receivable, unbilled revenue (contract assets) and unearned revenue or payments on account (contract liabilities) Revenue from Contract with Customer [Text Block] Purchase of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Weighted Average Remaining Contractual Life 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] Additional paid-in capital Additional Paid in Capital, Common Stock Additional Paid-in Capital Additional Paid-in Capital [Member] Balance Sheet Location [Axis] Balance Sheet Location [Axis] Total Assets Assets Share of losses in equity method investments Loss on equity method investments Income (Loss) from Equity Method Investments Share Repurchase Program Share Repurchase Program [Axis] Cover [Abstract] Subsequent Events Subsequent Events [Text Block] Non-cash stock compensation expense APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Amortization of financing costs and debt discount Amortization of Debt Issuance Costs U.S. UNITED STATES Restructuring and Related Activities [Abstract] Restructuring and Related Activities [Abstract] Non-current other liabilities Other Liabilities, Noncurrent Shares vested (in USD per share) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period, Weighted Average Grant Date 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Component [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Basic (in shares) Weighted average number of ordinary shares outstanding for basic net income per ordinary share (in shares) Weighted Average Number of Shares Outstanding, Basic Income from operations Income from operations Operating Income (Loss) Schedule of Indefinite-Lived Intangible Assets [Table] Schedule of Indefinite-Lived Intangible Assets [Table] Cash flows from operating activities: Net Cash Provided by (Used in) Operating Activities, Continuing Operations [Abstract] Statement [Line Items] Statement [Line Items] Change in unbilled services (unbilled revenue) Increase in unbilled services (unbilled revenue) Increase (Decrease) In Contract With Customer, Asset, Gross, Current Increase (Decrease) In Contract With Customer, Asset, Gross, Current Schedule of Outstanding Debt Schedule of Debt [Table Text Block] Customer relationships Customer Relationships [Member] Type of Restructuring [Domain] Type of Restructuring [Domain] Other Restructuring Costs Other Restructuring Costs Other Liabilities