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shares granted Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Grants in Period Financial instruments measured at fair value on a recurring basis Fair Value Measurement and Measurement Inputs, Recurring and Nonrecurring [Text Block] Interest and other borrowing costs Interest and Debt Expense Long-term Investments Equity Method Investments and Joint Ventures Disclosure [Text Block] Discount rate Defined Benefit Plan, Assumptions Used Calculating Net Periodic Benefit Cost, Discount Rate Total Revenues Revenues Reconciliation of unrecognized tax benefits Reconciliation Of Unrecognized Tax Benefits [Text Block] Reconciliation Of Unrecognized Tax Benefits Stock-Based Payments Share-Based Payment Arrangement [Text Block] Entity Address, City or Town Entity Address, City or Town Operating Leases Lessee, Leases [Policy Text Block] Concentration Risk Threshold Percentage [Axis] Concentration Risk Threshold Percentage [Axis] Concentration Risk Threshold Percentage Total expense for stock payments Compensation expense Share-Based Payment Arrangement, Expense Underlying Asset Class [Domain] Underlying Asset Class [Domain] Interest and penalties recognized in the consolidated statements of income Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense Comprehensive Income (Loss) Note [Text Block] Comprehensive Income (Loss) Note [Text Block] Number of shares cancelled Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Forfeited in Period Finance Lease, Expense Finance Lease, Expense Finance Lease, Expense Assumptions Used to Determine End-of-Year Benefit Obligation: Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract] Business Acquisition [Axis] Business Acquisition [Axis] Weighted average useful life for the amortizable intangible assets Schedule of Finite-Lived Intangible Assets [Table Text Block] Property, Plant and Equipment, Net [Abstract] Property, Plant and Equipment, Net [Abstract] Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year Dividends or Other Earnings Paid on Equity Awards not Otherwise Reflected in Total Compensation for Covered Year [Member] Derivative investments, net Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax Revenue from Contract with Customer [Text Block] Revenue from Contract with Customer [Text Block] Document Fiscal Year Focus Document Fiscal Year Focus Debt Instrument, Name [Domain] Debt Instrument, Name [Domain] Total Assets at Fair Value Assets, Fair Value Disclosure Income before income taxes: Foreign Income (Loss) from Continuing Operations before Income Taxes, Foreign 2025 Finite-Lived Intangible Asset, Expected Amortization, Year Five Document Period End Date Document Period End Date Class B Common Stock, Class B2 [Member] Class B Common Stock, Class B2 [member] Class B Common Stock, Class B2 [Member] Total Operating Lease Payments Lessee, Operating Lease, Liability, to be Paid Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number Number of shares outstanding at December 31 (shares) Number of shares outstanding at December 31 (shares) Share-Based Compensation Arrangement by Share-Based Payment Award, Equity Instruments Other than Options, Nonvested, Number Line of Credit Facility, Lender [Domain] Line of Credit Facility, Lender [Domain] Insider Trading Arrangements [Line Items] Gain (Loss) on Disposition of Stock in Subsidiary or Equity Method Investee Gain (Loss) on Disposition of Stock in Subsidiary or Equity Method Investee Business Combinations Business Combinations and Other Purchase of Business Transactions, Policy [Policy Text Block] Capital Leases Future Minimum Payments [Abstract] Capital Leases Future Minimum Payments [Abstract] Capital Leases Future Minimum Payments [Abstract] 2027 Lessee, Operating Lease, Liability, to be Paid, Year Three EBS Foreign Exchange EBS Foreign Exchange [Member] EBS Foreign Exchange Accumulated benefit obligation Defined Benefit Plan, Accumulated Benefit Obligation Actuarial Losses [Roll Forward] Actuarial Losses [Roll Forward] Actuarial Losses [Roll Forward] €15.0 million fixed rate notes due May 2023 [Member] 750 million fixed rate notes due March 2025 [Member] 750 million fixed rate notes due March 2025 [Member] Class B Common Stock, Class B1 [Member] Class B Common Stock, Class B1 [member] Class B Common Stock, Class B1 [Member] Document Transition Report Document Transition Report Annual stipend allowance in shares of stock Annual Stipend Allowance In Cash Annual stipend allowance in cash Lessee, Operating Lease, Renewal Term Operating Lease Renewal Term Operating Lease Renewal Term Investments in business ventures Payments to Acquire Other Investments Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value, Recurring and Nonrecurring [Table] Entity Current Reporting Status Entity Current Reporting Status Retained Earnings [Member] Retained Earnings [Member] Contingent liability to SGX, amount of irrevocable letters of credit Guarantee Collateral Guarantee Collateral Director Stock Plan; Class A Shares [Member] Director Stock Plan; Class A Shares [Member] Director Stock Plan; Class A Shares [Member] Restricted Stock Units (RSUs) [Member] Restricted Stock Units (RSUs) [Member] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Executive Category: Executive Category [Axis] Payments to Acquire Investments Payments to Acquire Investments Taxes on income Schedule of Components of Income Tax Expense (Benefit) [Table Text Block] Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration Deferred Tax Assets, Operating Loss Carryforwards, Subject to Expiration Statement of Income Location, Balance [Domain] Statement of Income Location, Balance [Domain] Purchases of available-for-sale marketable securities Payments to Acquire Debt Securities, Available-for-Sale Company Selected Measure Name Company Selected Measure Name Accounts Payable and Accrued Liabilities Other Liabilities