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[Abstract] Unbilled revenue Increase (Decrease) in Contract with Customer, Asset Risk-free interest rate Share-Based Compensation Arrangement by Share-Based Payment Award, Fair Value Assumptions, Risk Free Interest Rate Total Liabilities and Shareholders' Equity Liabilities and Equity Amortization of financing costs and debt discount Amortization of Debt Issuance Costs Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Goodwill [Roll Forward] Goodwill [Roll Forward] Rest of World Rest of World [Member] Rest of World [Member] Organization, Consolidation and Presentation of Financial Statements [Abstract] Level 2 Fair Value, Inputs, Level 2 [Member] Current Fiscal Year End Date Current Fiscal Year End Date Interest and related penalties Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued Lease imputed interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Finite-Lived Intangible Assets [Line Items] Finite-Lived Intangible Assets [Line Items] Diluted (in USD per share) Earnings Per Share, Diluted Shares vesting period Share-Based Compensation Arrangement by Share-Based Payment Award, Award Vesting Period Share issue costs Payments of Stock Issuance Costs Non-cash stock compensation expense APIC, Share-Based Payment Arrangement, Increase for Cost Recognition 2027 and thereafter Long-Term Debt, Maturity, Year Four And Thereafter Long-Term Debt, Maturity, Year Four And Thereafter Net intangible assets at fair value Finite-Lived Intangible Assets, Fair Value Disclosure Total current liabilities Liabilities, Current Year 2 Lessee, Operating Lease, Liability, to be Paid, Year Two Non-current income taxes payable Accrued Income Taxes, Noncurrent Liability for unrecognized tax benefit Unrecognized Tax Benefits Facility liability Facility Liability [Member] Facility Liability Restructuring Cost and Reserve [Line Items] Restructuring Cost and Reserve [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 [Line Items] Share Repurchase Program Share Repurchase Program [Axis] Revenue, remaining performance obligation Revenue, Remaining Performance Obligation, Amount Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Schedule of Operating Lease Maturity Lessee, Operating Lease, Liability, Maturity [Table Text Block] Buyback Program Buyback Program [Member] Buyback Program [Member] Fair Value Disclosures [Abstract] Interest expense Interest Expense Derivative Instruments and Hedging Activities Disclosure [Abstract] Trade names & brands Trade Names [Member] Credit Facility [Axis] Credit Facility [Axis] Equity [Abstract] Equity [Abstract] Shares vested (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Vested in Period 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] Ordinary shares which have been reserved for issuance (in shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Number of Shares Authorized Schedule of Distribution of Depreciation and Amortization by Geographical Area Long-Lived Assets by Geographic Areas [Table Text Block] Derivative, fixed interest rate Derivative, Fixed Interest Rate Schedule of Disaggregation of Revenue Disaggregation of Revenue [Table Text Block] Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Net decrease in cash and cash equivalents Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents, Period Increase (Decrease), Including Exchange Rate Effect Summary of details of movement in restructuring charges Schedule of Restructuring Reserve by Type of Cost [Table Text Block] Effect of dilutive share options and other awards outstanding under share based compensation programs (in shares) Weighted Average Number of Shares Outstanding, Diluted, Adjustment Summary of Restructuring Charges Restructuring and Related Costs [Table Text Block] Entity Central Index Key Entity Central Index Key Interest income Investment Income, Interest Measurement Frequency [Axis] Measurement Frequency [Axis] Weighted Average Grant Date Fair Value Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Abstract] Variable Rate Component [Domain] Variable Rate Component [Domain] Variable Rate Component [Domain] Finite-Lived Intangible Assets by Major Class [Axis] Finite-Lived Intangible Assets by Major Class [Axis] Schedule of Share-based Compensation Arrangements by Share-based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Business Combination, Consideration Transferred Business Combination, Consideration Transferred Percentage change in unearned revenue (payments on account) Increase (Decrease) In Contract With Customer, Liability, Gross, Current, Percent Increase (Decrease) In Contract with Customer, Liability, Gross, Current, Percent ASSETS Assets [Abstract] Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Current bank credit lines and loan facilities Line of Credit, Current Revenue, remaining performance obligation percentage Revenue, Remaining Performance Obligation, Percentage 2024 Long-Term Debt, Maturity, Year One Stock compensation expense Share-Based Payment Arrangement, Noncash Expense Weighted average grant date fair value Share-Based Compensation Arrangement by Share-Based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value Repayments of senior debt Repayments of Senior Debt Variable Rate [Axis] Variable Rate [Axis] Non-current other liabilities Other Liabilities, Noncurrent Share of losses in equity method investments Loss on equity method investments Income (Loss) from Equity Method Investments Purchase of property, plant and equipment Payments to Acquire Property, Plant, and Equipment Disaggregation of Revenue [Line Items] Disaggregation of Revenue [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 reconciliation of number of shares used in computation of basic and diluted net income per ordinary share Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Line of credit facility, interest rate at period end Line of Credit Facility, Interest Rate at Period End Right-of-use assets obtained in exchange for lease obligations Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Direct costs Cost of Sales [Member] Customer [Domain] Customer [Domain] Other Liabilities