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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 stock Dividends, Cash Compensation and benefits Labor and Related Expense Leases Lessee, Operating Leases [Text Block] 2027 Long-Term Debt, Maturity, Year One Basic (in dollars per share) Earnings per common share, 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 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] 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 Metals Metal [Member] Metal [Member] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Derivative Contract [Domain] Derivative Contract [Domain] Foreign currency translation Goodwill, Foreign Currency Translation, Gain (Loss) Equity Awards Adjustments Equity Awards Adjustments [Member] Schedule of Fair value of Debt Instruments Fair value of Debt Instruments [Table Text Block] [Table Text Block] for Fair value of Debt Instruments [Table] 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] Class B Common Stock, Class B-4 Class B Common Stock, Class B4 [member] Class B Common Stock, Class B4 [Member] Other liabilities Increase (Decrease) in Other Operating Liabilities Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Licensing and other fee agreements Licensing Fees Licensing Fees Tabular List, Table Tabular List [Table Text Block] 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 Clearing and transaction fees clearing and transaction fees [Member] clearing and transaction fees [Member] 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 June 30, 2026 and December 31, 2025; no shares issued and outstanding as of June 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 $500.0 million fixed rate notes due June 2028, stated rate of 3.75% $500.0 Million Fixed Rate Notes Due June 2028, Interest Rate Equal To 3.75% [Member] $500.0 Million Fixed Rate Notes Due June 2028, Interest Rate Equal To 3.75% 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 Total finance lease expense Finance Lease, Expense Finance Lease, Expense 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 Class B Common Stock, Class B-2 Class B Common Stock, Class B2 [member] Class B Common Stock, Class B2 [Member] Total operating lease expense included in other expense Operating Lease, Expense Company Selected Measure Amount Company Selected Measure Amount 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 EBS foreign exchange EBS Foreign Exchange [Member] EBS Foreign Exchange 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) Class B Common Stock, Class B-1 Class B Common Stock, Class B1 [member] Class B Common Stock, Class B1 [Member] 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 Renew the leases for up to Operating Lease Renewal Term Operating Lease Renewal Term 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] Contingent liability to SGX, amount of irrevocable letters of credit Guarantee Collateral Guarantee Collateral Restatement Determination Date: Restatement Determination Date [Axis] Schedule of Accumulated Other Comprehensive Income (Loss) Schedule of Accumulated Other Comprehensive Income (Loss) [Table Text Block] Change in performance bond and guaranty fund contributions Change in performance bond and guaranty fund contributions Change in performance bond and guaranty fund contributions Revenues Revenues [Abstract] $700.0 million Fixed Rate Notes Due June 2048 $700.0 million Fixed Rate Notes Due June 2048 [Member] $700.0 million Fixed Rate Notes Due June 2048 Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block]