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Country Code Entity Incorporation, State or Country Code Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] Restricted cash Short-term restricted cash Restricted Cash and Cash Equivalent, Current Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year Vesting Date Fair Value of Equity Awards Granted and Vested in Covered Year [Member] Basis of Presentation Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Debt Instrument [Axis] Debt Instrument [Axis] Stock-based compensation Share-Based Payment Arrangement, Noncash Expense 2028 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two Dividends on common and preferred stock Dividends, Cash Compensation and benefits Labor and Related Expense $750.0 million fixed rate notes due September 2043, stated rate of 5.30% $750.0 million Fixed Rate Notes Due September 2043 Interest Equal To 5.30% [Member] $750.0millionFixedRateNotesDueSeptember2043InterestEqualTo5.3% Leases Lessee, Operating Leases [Text Block] 2027 Long-Term Debt, Maturity, Year One Basic (in dollars per share) Earnings Per Share, Basic Deferred revenue Deferred Revenue Total current assets Assets, Current Insider Trading Arrangements [Line Items] Award Type Award Type [Axis] Short-term lease cost Short-Term Lease, Cost Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Accounts receivable, net of allowance of $9.1 and $10.0 Accounts Receivable, after Allowance for Credit Loss, Current $700.0 million fixed rate notes due June 2048, stated rate of 4.15% $700.0 Million Fixed Rate Notes Due June 2048, Interest Equal To 4.15% [Member] $700.0 Million Fixed Rate Notes Due June 2048, Interest Equal To 4.15% Stock-based compensation Shares Granted, Value, Share-Based Payment Arrangement, before Forfeiture Retained earnings Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] $750.0 million fixed rate notes due March 2032, stated rate of 2.65% $750.0 Million Fixed Rate Notes Due March 2032, Interest Equal To 2.65% [Member] $750.0 Million Fixed Rate Notes Due March 2032, Interest Equal To 2.65% Performance Bonds and Guaranty Fund Contributions Performance Bonds and Guaranty Fund Contributions [Text Block] Performance Bonds and Guaranty Fund Contributions [Text Block] Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table Aggregate Change in Present Value of Accumulated Benefit for All Pension Plans Reported in Summary Compensation Table [Member] Awards Close in Time to MNPI Disclosures Awards Close in Time to MNPI Disclosures [Table] Common Stock Common Stock [Member] Operating lease cost Operating Lease, Cost Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract]  Amortization Expense Intangible Asset, Finite-Lived, after Accumulated Amortization, Estimated Amortization Expense, Fiscal Year Maturity [Abstract] Derivative Contract [Domain] Derivative Contract [Domain] Foreign currency translation Goodwill, Foreign Currency Translation, Gain (Loss) Equity Awards Adjustments Equity Awards Adjustments [Member] Total Liabilities and Equity Liabilities and Equity Employee Stock Option Share-Based Payment Arrangement, Option [Member] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Other liabilities Increase (Decrease) in Other Operating Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Tabular List, Table Tabular List [Table Text Block] Additional Line of Credit Additional Line Of Credit [Member] Additional Line Of Credit Weighted average discount rate Weighted Average Discount Rate Operating Lease Weighted Average Discount Rate Operating Lease Other non-operating income (expense) Distribution of interest earned on collateral reinvestments Other Nonoperating Income (Expense) 2031 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Five 2029 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Three Performance bonds and guaranty fund contributions Restricted cash and restricted cash equivalents (performance bonds and guaranty fund contributions) Good Faith and Margin Deposit with Broker-Dealer Remainder of 2026 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Remainder of Fiscal Year Name Awards Close in Time to MNPI Disclosures, Individual Name Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested Year-end Fair Value of Equity Awards Granted in Covered Year that are Outstanding and Unvested [Member] Preferred stock, shares authorized (in shares) Preferred Stock, Shares Authorized Preferred stock, $0.01 par value, 10,000 shares authorized at September 30, 2026 and December 31, 2025; no shares issued and outstanding as of September 30, 2026 and 4,584 issued and outstanding as of December 31, 2025 Preferred Stock, Value, Issued Adjustment to Compensation: Adjustment to Compensation [Axis] Class of Stock [Domain] Class of Stock [Domain] Rule 10b5-1 Arrangement Terminated Rule 10b5-1 Arrangement Terminated [Flag] Aggregate Erroneous Compensation Amount Aggregate Erroneous Compensation Amount Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Interest paid Interest Paid, Excluding Capitalized Interest, Operating Activity Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Amortizable intangible assets Translation Adjustment Functional to Reporting Currency, Increase (Decrease), Gross of Tax Add: overdistributed earnings allocated to preferred stock Undistributed Earnings (Loss) Allocated to Participating Securities, Basic Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total Assets at Fair Value Assets, Fair Value Disclosure 2031 Finance Lease, Liability, to be Paid, Year Five Name Measure Name Accounts payable Accounts Payable, Current Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Other Other Noncash Income (Expense) 2031 Lessee, Operating Lease, Liability, to be Paid, Year Five Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Entity Filer Category Entity Filer Category Indefinite-lived Intangible Assets by Major Class [Axis] Intangible Asset, Indefinite-Lived, Class [Axis] Guarantor Obligations, Nature [Domain] Guarantor Obligations, Nature [Domain] Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent Finance Leases Finance Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] Par Value Long-Term Debt, Fiscal Year Maturity [Abstract] Total operating lease expense included in other expense Operating Lease, Expense Company Selected Measure Amount Company Selected Measure Amount Licensing and other fee agreements Licensing Fees Licensing Fees 2031 Long-Term Debt, Maturity, Year Five Current Assets: Assets, Current [Abstract] Weighted average remaining lease term (in months) Operating Lease, Weighted Average Remaining Lease Term Non-PEO NEO Non-PEO NEO [Member] Amortization of net actuarial (gains) losses included in compensation and benefits expense Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss), Reclassification Adjustment from AOCI, before Tax Entity Address, Street Address Entity Address, Address Line One Income tax provision Income Tax Expense (Benefit) Award Timing Method Award Timing Method [Text Block] Net change in cash, cash equivalents, restricted cash and restricted cash equivalents Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Period Increase (Decrease), Including Exchange Rate Effect and Discontinued Operation Forgone Recovery, Explanation of Impracticability Forgone Recovery, Explanation of Impracticability [Text Block] Net change in defined benefit plans arising during the period Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, before Tax Net Income Net Income Net Income (Loss) Attributable to Parent Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Statement [Table] Statement [Table] $500.0 million Fixed Rate Notes Due June 2028 $500.0 million Fixed Rate Notes Due June 2028 [Member] $500.0 million Fixed Rate Notes Due June 2028 Restatement Determination Date: Restatement Determination Date [Axis] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Interest rates Interest Rate [Member] Interest Rate [Member] Revenues Revenues [Abstract] One-time charges and miscellaneous revenues One-time charges and miscellaneous revenues [Member] One-time charges and miscellaneous revenues [Member] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]