Trading Arrangements, by Individual Trading Arrangements, by Individual [Table] Weighted average shares outstanding: Weighted Average Number of Shares Outstanding, Diluted [Abstract] Trading Arrangement: Trading Arrangement [Axis] Title of 12(b) Security Title of 12(b) Security Subsequent Event Subsequent Event [Member] Document Fiscal Year Focus Document Fiscal Year Focus Remaining performance obligations, expected timing of satisfaction, period Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Period Adjustment to Compensation, Amount Adjustment to Compensation Amount Customer Customer [Axis] Segment Reporting [Abstract] Segment Reporting [Abstract] Schedule of Estimated Amortization Expense for the Remainder of the Year and Succeeding Years Intangible Asset, Finite-Lived, and Capitalized Cost, Software to be Sold, Leased, or Marketed, Estimated Amortization Expense [Table Text Block] Common stock (par value $0.01; 750.0 common shares authorized; 134.5 and 134.4 common shares issued and 72.7 and 73.6 common shares outstanding at June 30, 2026 and December 31, 2025, respectively) Common Stock, Value, Issued 2027 Lessee, Operating Lease, Liability, to be Paid, Year One Accrued compensation and related benefits Employee-related Liabilities, Current Adjusted EBITDA Operating Segment Profitability The operating profitability of each segment, reflecting adjusted earnings before interest, taxes, depreciation and amortization. Trademarks Trademarks [Member] Schedule of Senior Unsecured Notes Schedule of Long-Term Debt Instruments [Table Text Block] Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis] Analytics Analytics Segment [Member] Analytics. Increase/(decrease) Increase (Decrease) In Contract With Customer, Liability, Current Increase (decrease) in contract with customer liability, current. Line of Credit Line of Credit [Member] Restatement Determination Date Restatement Determination Date Amortization expense of acquired intangible assets Acquired Intangible Assets [Member] Acquired intangible assets. Amendment Flag Amendment Flag Goodwill [Line Items] Goodwill [Line Items] Current liabilities: Liabilities, Current [Abstract] Average Price Paid Per Share (in USD per Share) Shares Acquired, Average Cost Per Share Addition to credit loss expense Accounts Receivable, Credit Loss Expense (Reversal) Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Foreign currency translation adjustments Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, before Tax, Portion Attributable to Parent Leases [Abstract] Leases [Abstract] Other comprehensive income (loss): Other Comprehensive Income (Loss), Net of Tax [Abstract] Acquired Finite Lived Intangible Assets [Line Items] Intangible Asset, Finite-Lived, Acquired [Line Items] Maturity Date Debt Instrument, Maturity Date 5.250% senior unsecured notes due 2035 Five Point Two Five Zero Percent Senior Unsecured Notes Due Two Thousand Thirty Five [Member] Five Point Two Five Zero Percent Senior Unsecured Notes Due Two Thousand Thirty Five Adjustment to Non-PEO NEO Compensation Footnote Adjustment to Non-PEO NEO Compensation Footnote [Text Block] Entity Address, State or Province Entity Address, State or Province Foreign currency translation adjustments, net Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax, Portion Attributable to Parent PEO Total Compensation Amount PEO Total Compensation Amount Common stock, par value (in USD per share) Common Stock, Par or Stated Value Per Share Share Repurchase Program Share Repurchase Program [Domain] Basic (in USD per share) Basic weighted average common shares outstanding (in shares) Weighted Average Number of Shares Outstanding, Basic 3.250% senior unsecured notes due 2033 Three Point Two Five Zero Percent Senior Unsecured Notes Due Two Thousand Thirty Three [Member] Three point two five zero percent senior unsecured notes due two thousand thirty three. Outstanding Aggregate Erroneous Compensation Amount Outstanding Aggregate Erroneous Compensation Amount Number of reportable segments Number of Reportable Segments Total current liabilities Liabilities, Current 2030 Lessee, Operating Lease, Liability, to be Paid, Year Four Customer relationships Customer Relationships [Member] 3.875% senior unsecured notes due 2031 Three Point Eight Seven Five Percent Senior Unsecured Notes Due Two Thousand Thirty One [Member] Three point eight seven five percent senior unsecured notes due two thousand thirty one. Total EMEA EMEA [Member] Entity Address, City or Town Entity Address, City or Town Blackrock Inc Blackrock Inc [Member] BlackRock Inc. Long-term operating lease liabilities Increase Decrease In Long Term Operating Lease Liabilities Increase (decrease) in long-term operating lease liabilities. Total Asia & Australia Asia And Australia [Member] Asia and Australia. Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Share-Based Compensation Arrangement by Share-Based Payment Award [Line Items] Statement of Financial Position [Abstract] Statement of Financial Position [Abstract] Award Timing MNPI Disclosure Award Timing MNPI Disclosure [Text Block] Basis of Presentation Basis of Accounting, Policy [Policy Text Block] Intangible assets, net Net intangible assets Intangible Asset, Finite-Lived, after Accumulated Amortization Peer Group Total Shareholder Return Amount Peer Group Total Shareholder Return Amount Interest rate om the revolving loans Line of Credit Facility, Interest Rate at Period End Sublease income Sublease Income Accumulated amortization Intangible Asset, Finite-Lived, Accumulated Amortization Recurring subscriptions Recurring Subscriptions [Member] Recurring subscriptions. Total Shareholder Return Vs Peer Group Total Shareholder Return Vs Peer Group [Text Block] Line of credit facility, maximum borrowing capacity Line of Credit Facility, Maximum Borrowing Capacity Non-Rule 10b5-1 Arrangement Terminated Non-Rule 10b5-1 Arrangement Terminated [Flag] United States UNITED STATES Subsequent Event Type Subsequent Event Type [Axis] Concentration Risk Type Concentration Risk Type [Axis] Debt Instrument [Table] Schedule of Long-Term Debt Instruments [Table] Class Of Treasury Stock [Table] Class of Treasury Stock [Table] Recent Accounting Pronouncements New Accounting Pronouncements, Policy [Policy Text Block] Acquired technology and software Acquired Technology And Software [Member] Acquired technology and software. Property, equipment and leasehold improvements in other accrued liabilities Capital Expenditures Incurred but Not yet Paid Deferred revenue Increase (Decrease) in Contract with Customer, Liability Schedule of Segment Profitability and Reconciliation to Net Income Segment Reporting [Table Text Block] Use of Estimates Use of Estimates, Policy [Policy Text Block] Amortization of debt origination fees Amortization of Debt Issuance Costs Other comprehensive income (loss), net of tax Other comprehensive income (loss), net of tax Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent Schedule of Changes in the Company’s Level 3 Financial Liabilities Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block] Carrying value Long-Term Debt Summary of Maturities of Operating Lease Liability Lessee, Operating Lease, Liability, to be Paid, Maturity [Table Text Block] Income taxes payable Increase (Decrease) in Income Taxes Payable Document Period End Date Document Period End Date Changes in assets and liabilities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity, Increase (Decrease) in Operating Capital [Abstract] Net cash used in investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation Equity Awards Adjustments, Excluding Value Reported in Compensation Table Equity Awards Adjustments, Excluding Value Reported in the Compensation Table [Member] 2028 Lessee, Operating Lease, Liability, to be Paid, Year Two SHAREHOLDERS' EQUITY (DEFICIT) Equity [Text Block] Operating expenses: Costs and Expenses [Abstract] Security Exchange Name Security Exchange Name Prepaid income taxes Increase (Decrease) in Prepaid Taxes Treasury shares, at cost (61.8 and 60.8 common shares held at June 30, 2026 and December 31, 2025, respectively) Treasury Stock, Common, Value 5.150% senior unsecured notes due 2036 Five Point One Five Zero Percent Senior Unsecured Notes Due Two Thousand Thirty Six [Member] Five Point One Five Zero Percent Senior Unsecured Notes Due Two Thousand Thirty Six Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Entity Shell Company Entity Shell Company Revenue from Contract with Customer, Segment Benchmark Revenue from Contract with Customer, Segment Benchmark [Member] Change in fair value Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Gain (Loss) Included in Earnings Other accrued liabilities Operating Lease, Liability, Current Increase/(decrease) Accounts Receivable Increase (Decrease) Accounts receivable increase (decrease). Contingent consideration period Business Combination, Contingent Consideration Period Business Combination, Contingent Consideration Period Statement of Comprehensive Income [Abstract] Statement of Comprehensive Income [Abstract] EARNINGS PER COMMON SHARE Earnings Per Share [Text Block] Name Outstanding Recovery, Individual Name Earnings per share: Earnings Per Share [Abstract] Award Timing, How MNPI Considered Award Timing, How MNPI Considered [Text Block] Document Fiscal Period Focus Document Fiscal Period Focus Peer Group Issuers, Footnote Peer Group Issuers, Footnote [Text Block] Income tax effect Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax, Attributable to Parent Total liabilities Liabilities Trading Symbol Trading Symbol Geographical Geographical [Domain] Schedule of Interest Payments Due Attributable to Outstanding indebtedness Interest Income and Interest Expense Disclosure [Table Text Block] Capital expenditures Payments to Acquire Property, Plant, and Equipment Other Other Europe Middle East And Africa Countries [Member] Other Europe, Middle East and Africa Countries. Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year Prior Year End Fair Value of Equity Awards Granted in Any Prior Year that Fail to Meet Applicable Vesting Conditions During Covered Year [Member] Pension Adjustments Prior Service Cost Pension Adjustments Prior Service Cost [Member] Income taxes payable Accrued Income Taxes, Current Company Selected Measure Name Company Selected Measure Name Income Tax Disclosure [Abstract] Income Tax Disclosure [Abstract] Principal amount outstanding Total debt Long-Term Debt, Gross Other accrued liabilities Increase (Decrease) in Other Accrued Liabilities Credit Facility Credit Facility [Domain] Cash flows from operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation [Abstract] Index Index Segment [Member] Index. Compensation Amount Outstanding Recovery Compensation Amount Individual: Individual [Axis] Schedule Of Revenue Recognition [Table] Schedule Of Revenue Recognition [Table] Schedule of revenue recognition. Diluted (in USD per share) Diluted weighted average common shares outstanding (in USD per share) Weighted Average Number of Shares Outstanding, Diluted Disaggregation Of Revenue [Line Items] Disaggregation of Revenue [Line Items] Entity Emerging Growth Company Entity Emerging Growth Company Equity Valuation Assumption Difference, Footnote Equity Valuation Assumption Difference, Footnote [Text Block] Deferred revenue Contract with Customer, Liability, Current [Roll Forward] Contract with Customer, Liability, Current Underlying Security Market Price Change Underlying Security Market Price Change, Percent Dividends declared Dividends Deferred taxes Deferred Income Taxes and Tax Credits Variable rate Revolving Loan Commitments Variable rate revolving loans Credit Agreement [Member] Credit Agreement Less: Interest Lessee, Operating Lease, Liability, Undiscounted Excess Amount Discrete tax benefit from legal entity restructuring Effective Income Tax Rate Reconciliation, Internal Legal Entity Restructuring, Amount Effective Income Tax Rate Reconciliation, Internal Legal Entity Restructuring, Amount Schedule Of Share Based Compensation Arrangements By Share Based Payment Award [Table] Schedule of Share-Based Compensation Arrangements by Share-Based Payment Award [Table] Other non-current assets Increase (Decrease) in Other Noncurrent Assets Revenue from Contract with Customer [Abstract] Revenue from Contract with Customer [Abstract] Effect of dilutive securities (in shares) Weighted Average Number of Shares Outstanding, Diluted, Adjustment Other Increase (Decrease) in Other Operating Assets and Liabilities, Net Operating cash flows used for operating leases Operating Lease, Payments Award Timing Predetermined Award Timing Predetermined [Flag] Restricted cash, current Restricted Cash, Current Treasury Stock Treasury Stock, Common [Member] 2025 Repurchase Program 2025 Repurchase Program [Member] 2025 Repurchase Program Intangible Asset, Goodwill and Other [Abstract] Intangible Asset, Goodwill and Other [Abstract] Adjustment To PEO Compensation, Footnote Adjustment To PEO Compensation, Footnote [Text Block] Compensation payable in common stock APIC, Share-Based Payment Arrangement, Increase for Cost Recognition Amortization expense of internally developed capitalized software Internally developed capitalized software Software, Internally Developed [Member] Effective tax rate (as percent) Effective Income Tax Rate Reconciliation, Percent Organization, Consolidation and Presentation of Financial Statements [Abstract] Organization, Consolidation and Presentation of Financial Statements [Abstract] Total lease payments Lessee, Operating Lease, Liability, to be Paid All Executive Categories All Executive Categories [Member] Pension Adjustments Service Cost Pension Adjustments Service Cost [Member] Preferred stock, par value (in USD per share) Preferred Stock, Par or Stated Value Per Share Depreciation and amortization of property, equipment and leasehold improvements Depreciation Selling and marketing Selling and Marketing Expense Right of use assets Operating Lease, Right-of-Use Asset Concentration Risk Type Concentration Risk Type [Domain] Accounting Changes and Error Corrections [Abstract] Accounting Changes and Error Corrections [Abstract] Schedule of Computation of Basic and Diluted EPS Schedule of Earnings Per Share, Basic and Diluted [Table Text Block] Debt Disclosure [Abstract] Debt Instrument, Name Debt Instrument, Name [Domain] SEGMENT INFORMATION Segment Reporting [Text Block] Thereafter Lessee Operating Lease Liability Payments Due After Year Four Lessee, operating lease, liability, payments, due after year four. Payment of dividends Payments of Ordinary Dividends, Common Stock Expiration Date Trading Arrangement Expiration Date 2030 Long-Term Debt, Maturity, Year Four Schedule of Disaggregation of Operating Revenue Disaggregation of Revenue [Table Text Block] Schedule of Amortization Expense Related to Intangible Assets by Category Intangible Asset, Finite-Lived, Amortization Expense [Table Text Block] Non-Rule 10b5-1 Arrangement Adopted Non-Rule 10b5-1 Arrangement Adopted [Flag] Total Americas Americas [Member] Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table Aggregate Grant Date Fair Value of Equity Award Amounts Reported in Summary Compensation Table [Member] Schedule of Activity Related to Shares of Common Stock Issued and Repurchased Schedule of Common Stock Outstanding Roll Forward [Table Text Block] Business Combination [Line Items] Business Combination [Line Items] Aggregate Pension Adjustments Service Cost Aggregate Pension Adjustments Service Cost [Member] Senior Unsecured Notes Senior Unsecured Notes [Member] Senior unsecured notes. Common stock, shares authorized (in shares) Common Stock, Shares Authorized Exercise Price Award Exercise Price Cash flows from investing activities Cash Provided by (Used in) Investing Activity, Including Discontinued Operation [Abstract] Segment Reporting [Line Items] Segment Reporting [Line Items] Repurchase program authorizing the purchase of shares Share Repurchase Program, Authorized, Amount Document Quarterly Report Document Quarterly Report First interest payment date Debt Instruments First Interest Payment Date Debt instruments first interest payment date. Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested Year-over-Year Change in Fair Value of Equity Awards Granted in Prior Years That are Outstanding and Unvested [Member] Segments Segments [Domain] Effect of exchange rate changes Effect of Exchange Rate on Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Including Discontinued Operation Accounts receivable (net of allowances of $7.2 and $6.4 at June 30, 2026 and December 31, 2025, respectively) Opening Closing Accounts Receivable, after Allowance for Credit Loss DEBT Debt Disclosure [Text Block] Deferred financing fees and premium remain unamortized Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net Awards Close in Time to MNPI Disclosures, Table Awards Close in Time to MNPI Disclosures [Table Text Block] Schedule Of Business Acquisitions By Acquisition [Table] Business Combination [Table] Equity Component Equity Component [Domain] PEO Actually Paid Compensation Amount PEO Actually Paid Compensation Amount Business Combination, Asset Acquisition, Transaction between Entities under Common Control, and Joint Venture Formation [Abstract] Total operating expenses Costs and Expenses Adoption Date Trading Arrangement Adoption Date Total Amount Dividends, Common Stock, Cash Debt instrument interest rate Debt Instrument, Interest Rate, Stated Percentage Total shareholders’ equity (deficit) Beginning Balance Ending Balance Equity, Attributable to Parent Other expense (income), net Other expense (income), net Nonoperating Income (Expense) ASSETS Assets [Abstract] Title Trading Arrangement, Individual Title Forgone Recovery due to Disqualification of Tax Benefits, Amount Forgone Recovery due to Disqualification of Tax Benefits, Amount Restatement does not require Recovery Restatement Does Not Require Recovery [Text Block] Present value of lease liabilities Operating Lease, Liability Insider Trading Policies and Procedures [Line Items] Accounts receivable, allowance for credit loss, current Balance at beginning of year Balance at ending of year Accounts Receivable, Allowance for Credit Loss, Current Insider Trading Policies and Procedures Adopted Insider Trading Policies and Procedures Adopted [Flag] Prepaid and other assets Prepaid Expense and Other Assets, Current Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] Repayment of borrowings Repayments of Debt Business Combination Business Combination [Domain] Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items] Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue and Long-Lived Asset [Line Items] Compensation Actually Paid vs. Net Income Compensation Actually Paid vs. Net Income [Text Block] Number of operating segments Number of Operating Segments Schedule of Change to Company's Goodwill Goodwill [Table Text Block] Entity Central Index Key Entity Central Index Key Additional paid in capital Additional Paid in Capital, Common Stock All Adjustments to Compensation All Adjustments to Compensation [Member] Business Combination Business Combination [Axis] Equity [Abstract] Equity [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] Net cash provided by operating activities Cash Provided by (Used in) Operating Activity, Including Discontinued Operation Remainder of 2026 Long-Term Debt, Maturity, Remainder of Fiscal Year Income Statement [Abstract] Income Statement [Abstract] Shareholders’ equity (deficit): Equity, Attributable to Parent [Abstract] Document Transition Report Document Transition Report Deferred tax assets Deferred Income Tax Assets, Net Stock Appreciation Rights (SARs) Stock Appreciation Rights (SARs) [Member] Total reportable segment operating revenues Reportable Segment, Aggregation before Other Operating Segment [Member] Schedule of Gross Carrying and Accumulated Amortization Amounts Related to Company's Intangible Assets Intangible Asset, Finite-Lived [Table Text Block] Schedule Of Acquired Finite Lived Intangible Asset By Major Class [Table] Intangible Asset, Finite-Lived, Acquired [Table] Debt instrument, basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate City Area Code City Area Code Variable Rate Variable Rate [Domain] Accumulated Other Comprehensive Income (Loss) AOCI Attributable to Parent [Member] All Individuals All Individuals [Member] SUBSEQUENT EVENTS Subsequent Events [Text Block] Amortization of right of use assets Operating Lease, Right-of-Use Asset, Periodic Reduction Fair value Debt Instrument, Fair Value Disclosure Schedule of Operating Revenues by Geographic Area Segment Reporting, Entity-Wide Information Not Provided as Part of Reportable Segment, Geographical Area, Revenue [Table Text Block] Name Forgone Recovery, Individual Name Contingent consideration liability noncurrent Business Combination, Contingent Consideration, Liability, Noncurrent Non-GAAP Measure Description Non-GAAP Measure Description [Text Block] Statement [Line Items] Statement [Line Items] Total assets Assets Maturity of Lease Liabilities Lessee, Operating Lease, Liability, to be Paid, Fiscal Year Maturity [Abstract] Preferred stock, shares issued (in shares) Preferred Stock, Shares Issued Pension and other post-retirement adjustments, net Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax and Reclassification Adjustment, Attributable to Parent Interest expense Interest Expense, Nonoperating PEO PEO [Member] 2028 Long-Term Debt, Maturity, Year Two Other non-current liabilities Other Liabilities, Noncurrent Goodwill Goodwill, beginning balance Goodwill, ending balance Goodwill Forgone Recovery due to Violation of Home Country Law, Amount Forgone Recovery due to Violation of Home Country Law, Amount Acquisitions Goodwill, Acquired During Period Thereafter Long-Term Debt, Maturity, After Year Four Long-Term Debt, Maturity, After Year Four Revenue recognized during period included in deferred revenue Contract with Customer, Liability, Revenue Recognized Subsequent Event Type Subsequent Event Type [Domain] Retained Earnings Retained Earnings [Member] Long-term operating lease liabilities Long-term operating lease liabilities Operating Lease, Liability, Noncurrent Revolving Credit Facility Revolving Credit Facility [Member] Thereafter Intangible Asset, Finite-Lived, Estimated Amortization Expense, After Year Four Finite-lived intangible assets, amortization expense, after year four. Erroneously Awarded Compensation Recovery Erroneously Awarded Compensation Recovery [Table] Increase (Decrease) in Stockholders' Equity [Roll Forward] Increase (Decrease) in Stockholders' Equity [Roll Forward] Common stock, shares outstanding (in shares) Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Outstanding Award Timing Disclosures [Line Items] Diluted (in USD per share) Earnings Per Share, Diluted Entity Current Reporting Status Entity Current Reporting Status Net cash (used in) financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation Total Shareholder Return Amount Total Shareholder Return Amount Shares withheld for tax withholding Share-Based Payment Arrangement, Decrease for Tax Withholding Obligation Prepaid and other assets Increase (Decrease) in Prepaid Expense and Other Assets Accrued compensation and related benefits Increase (Decrease) in Employee Related Liabilities Amortization of intangible assets Total amortization of intangible assets expense Intangible Asset, Finite-Lived, Amortization Expense Finite Lived Intangible Assets [Line Items] Intangible Asset, Finite-Lived [Line Items] Research and development Research and Development Expense Adjustments to reconcile net income to net cash provided by operating activities: Adjustment to Reconcile Net Income to Cash Provided by (Used in) Operating Activity [Abstract] 2029 Long-Term Debt, Maturity, Year Three Write-offs, net of recoveries Accounts Receivable, Allowance for Credit Loss, Writeoff 3.625% senior unsecured notes due 2031 Three Point Six Two Five Percent Senior Unsecured Notes Due Two Thousand Thirty One [Member] 3.625% Senior Unsecured Notes Due 2031 [Member]. Cash flows from financing activities Cash Provided by (Used in) Financing Activity, Including Discontinued Operation [Abstract] Operating revenues Revenue from Contract with Customer, Excluding Assessed Tax Property, equipment and leasehold improvements, net Property, Plant, and Equipment, after Accumulated Depreciation, Depletion, and Amortization Non-recurring Non Recurring [Member] Non-recurring. Adjusted EBITDA expenses Adjusted EBITDA Expense Adjusted EBITDA Expense Intangible Asset, Finite-Lived, Class Intangible Asset, Finite-Lived, Class [Axis] Exercise of stock options Stock Issued During Period, Value, Stock Options Exercised Equity Awards Adjustments, Footnote Equity Awards Adjustments, Footnote [Text Block] GOODWILL AND INTANGIBLE ASSETS, NET Intangible Asset and Goodwill [Text Block] Underlying Securities Award Underlying Securities Amount REVENUE RECOGNITION Revenue from Contract with Customer [Text Block] Vantager, Compass And PM Insights Vantager, Compass And PM Insights [Member] Vantager And Compass Other Payment for (Proceeds from) Other Investing Activity Schedule Of Introduction And Basis Of Presentation [Table] Schedule Of Introduction And Basis Of Presentation [Table] Schedule Of Introduction And Basis Of Presentation [Table] Weighted-average discount rate Operating Lease, Weighted Average Discount Rate, Percent Segment Reporting [Table] Segment Reporting [Table] Schedule of Maturities of Long-Term Debt Schedule of Maturities of Long-Term Debt [Table Text Block] Schedule of Components of Lease Expense (Income), Weighted-Average Remaining Lease Term and Discount Rate, and Other Information Related to the Company's Operating Leases Lease, Cost [Table Text Block] Contingent consideration liability current Business Combination, Contingent Consideration, Liability, Current All Trading Arrangements All Trading Arrangements [Member] Common Stock Issued Common Stock Issued [Member] Common stock issued. Beginning balance Ending Balance Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability Value Other Performance Measure, Amount Other Performance Measure, Amount Award Timing MNPI Considered Award Timing MNPI Considered [Flag] Operating income Operating Income (Loss) Schedule of Dividends Declared Per Common Share and Total Amounts Declared, Distributed and Deferred Dividends Declared [Table Text Block] Remaining performance obligations Revenue, Remaining Performance Obligation, Amount Common stock issued to Directors and (held in)/released from treasury Treasury Stock Value Issued To Directors Value of common stock issued, but undelivered, to directors. The timing of the delivery of the shares has been deferred until a future date. Current Fiscal Year End Date Current Fiscal Year End Date Proceeds from borrowings, net of discount Proceeds from Issuance of Debt Non-PEO NEO Average Total Compensation Amount Non-PEO NEO Average Total Compensation Amount ACQUISITIONS Business Combination [Text Block] Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year Change in Fair Value as of Vesting Date of Prior Year Equity Awards Vested in Covered Year [Member] Open Market Purchases of Common Stock Open Market Purchases Of Common Stock [Member] Open market purchases of common stock. Dividend declared per common share (in USD per share) Per Share (in USD per share) Common Stock, Dividends, Per Share, Declared Entity File Number Entity File Number Rule 10b5-1 Arrangement Adopted Rule 10b5-1 Arrangement Adopted [Flag] Recovery of Erroneously Awarded Compensation Disclosure [Line Items] Schedule of Changes in Allowance for Credit Losses Financing Receivable, Allowance for Credit Loss [Table Text Block] Common stock, shares issued (in shares) Beginning balance (in shares) Ending balance (in shares) Common Stock, Shares, Issued Measure: Measure [Axis] Common shares held (in shares) Beginning balance (in shares) Ending balance (in shares) Treasury Stock, Common, Shares Cost of revenues (exclusive of depreciation and amortization) Cost of Goods and Service, Excluding Depreciation, Depletion, and Amortization Equity Components Equity Components [Axis] 4.000% senior unsecured notes due 2029 Four Point Zero Zero Zero Percent Senior Unsecured Notes Due Two Thousand Twenty Nine [Member] Four point zero zero zero percent senior unsecured notes due two thousand twenty nine. Accounts receivable Increase (Decrease) in Accounts Receivable Product and Service Product and Service [Domain] Cash paid for income taxes, net of refunds received Income Tax Paid, after Refund Received Disaggregation Of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Variable Rate Variable Rate [Axis] Deferred tax liabilities Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Introduction And Basis Of Presentation [Line Items] Introduction And Basis Of Presentation [Line Items] Introduction and basis of presentation. Entity Small Business Entity Small Business Comprehensive income Comprehensive Income (Loss), Net of Tax, Attributable to Parent 2029 Lessee, Operating Lease, Liability, to be Paid, Year Three Termination Date Trading Arrangement Termination Date Weighted average useful life Intangible Asset, Finite-Lived, Acquired, Weighted-Average Amortization Period Subsequent Events [Abstract] Subsequent Events [Abstract] Payments Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Settlements Intangible assets Business Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived Compensation Actually Paid vs. Total Shareholder Return Compensation Actually Paid vs. Total Shareholder Return [Text Block] MNPI Disclosure Timed for Compensation Value MNPI Disclosure Timed for Compensation Value [Flag] Other non-current assets Other Assets, Noncurrent Document Type Document Type Business acquisitions, net of cash acquired Payments to Acquire Businesses, Net of Cash Acquired Fair Value as of Grant Date Award Grant Date Fair Value Schedule Of Goodwill [Table] Goodwill [Table] Pension and other post-retirement adjustments Other Comprehensive (Income) Loss, Defined Benefit Plan, before Tax, after Reclassification Adjustment, Attributable to Parent Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Stock repurchase program, remaining authorized repurchase amount Share Repurchase Program, Remaining Authorized, Amount 3.625% senior unsecured notes due 2030 Three Point Six Two Five Percent Senior Unsecured Notes Due Two Thousand Thirty [Member] Three point six two five percent senior unsecured notes due two thousand thirty. Arrangement Duration Trading Arrangement Duration Subsequent Event [Line Items] Subsequent Event [Line Items] Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Local Phone Number Local Phone Number Long-term deferred revenue Contract with Customer, Liability, Noncurrent Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Income before provision for income taxes Income (Loss) from Continuing Operations before Income Taxes, Noncontrolling Interest Insider Trading Policies and Procedures Not Adopted Insider Trading Policies and Procedures Not Adopted [Text Block] Commitments and Contingencies (see Note 7) Commitments and Contingencies Gross intangible assets Intangible Asset, Finite-Lived, before Accumulated Amortization Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] 2030 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Four Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] Goodwill [Roll Forward] Goodwill [Roll Forward] LIABILITIES AND SHAREHOLDERS’ EQUITY (DEFICIT) Liabilities and Equity [Abstract] Intangible Asset, Finite-Lived, Class Intangible Asset, Finite-Lived, Class [Domain] All Award Types Award Type [Domain] Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount Remainder of 2026 Lessee, Operating Lease, Liability, to be Paid, Remainder of Fiscal Year Sustainability and Climate Sustainability And Climate Segment [Member] Sustainability And Climate Segment Supplemental disclosure of cash flow information: Supplemental Cash Flow Information [Abstract] Total Number of Shares Repurchased (in shares) Shares repurchased under stock repurchase programs (in shares) Treasury Stock, Shares, Acquired 2027 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year One PEO Name PEO Name Acquisition-related integration and transaction costs Business Combination Integration Related Costs And Transaction Costs Business combination integration related costs and transaction costs. Common Stock Outstanding [Line Items] Common Stock Outstanding [Line Items] Common stock outstanding. Geographical Geographical [Axis] Payment of contingent consideration and deferred purchase price from acquisitions Payment for Contingent Consideration Liability, Financing Activities Concentrations Concentration Risk, Credit Risk, Policy [Policy Text Block] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Accounts receivable, net of allowances Accounts Receivable, Allowance for Credit Loss [Roll Forward] Common stock repurchased and held in treasury Dollar Value of Shares Repurchased Treasury Stock, Value, Acquired, Cost Method Cash, cash equivalents and restricted cash, beginning of period Cash, cash equivalents and restricted cash, end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Schedule Of Finite Lived Intangible Assets [Table] Intangible Asset, Finite-Lived [Table] Accounts payable Increase (Decrease) in Accounts Payable Other accrued liabilities Other Accrued Liabilities, Current Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Base Rate Base Rate [Member] Aggregate Erroneous Compensation Not Yet Determined Aggregate Erroneous Compensation Not Yet Determined [Text Block] Additions of contingent consideration Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Liability, Purchases Material Terms of Trading Arrangement Material Terms of Trading Arrangement [Text Block] Non-NEOs Non-NEOs [Member] 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] INTRODUCTION AND BASIS OF PRESENTATION Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block] Debt Instrument Debt Instrument [Axis] Supplemental disclosure of non-cash investing activities Supplemental Disclosures Of Non Cash Investing Activities [Abstract] Supplemental disclosures of non cash investing activities. Subsequent Event [Table] Subsequent Event [Table] Payments to acquire businesses, gross Payments to Acquire Businesses, Gross Stock-based compensation expense Share-Based Payment Arrangement, Noncash Expense 2028 Intangible Asset, Finite-Lived, Estimated Amortization Expense, Year Two Total lease costs Lease, Cost Customer Customer [Domain] LEASES Lessee, Operating Leases [Text Block] Other Other America Countries [Member] Other America Countries. 2027 Long-Term Debt, Maturity, Year One Long-Term Debt, Type Long-Term Debt, Type [Domain] Basic (in USD per share) Earnings Per Share, Basic Equity, Class of Treasury Stock [Line Items] Equity, Class of Treasury Stock [Line Items] Repurchase of common stock held in treasury Payments for Repurchase of Common Stock Deferred revenue Opening Closing Contract with Customer, Liability, Current Total current assets Assets, Current Insider Trading Arrangements [Line Items] Earnings per common share: Net Income Loss Per Share [Abstract] Net Income Loss Per Share Long-term debt Long-Term Debt, Excluding Current Maturities Award Type Award Type [Axis] Short-term lease costs Short-Term Lease, Cost Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Schedule of Company's Common Stock Repurchases Made on Open Market Class of Treasury Stock [Table Text Block] Retained earnings Retained Earnings (Accumulated Deficit) Product and Service Product and Service [Axis] Proprietary data Proprietary Databases And Systems [Member] Proprietary databases and systems. 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Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Aggregate purchase price Business Combination, Consideration Transferred Additional Paid in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Name Trading Arrangement, Individual Name Cash and cash equivalents (includes restricted cash of $3.7 and $3.7 at June 30, 2026 and December 31, 2025, respectively) Cash and Cash Equivalent Concentration Risk Benchmark Concentration Risk Benchmark [Domain] Capitalized software development costs Payments for Software Company Selected Measure Amount Company Selected Measure Amount First Street Technology, Inc First Street Technology, Inc [Member] First Street Technology, Inc Depreciation and amortization of property, equipment and leasehold improvements Depreciation, Depletion and Amortization Secured Overnight Financing Rate (SOFR) Secured Overnight Financing Rate (SOFR) [Member] Entity Address, Address Line Two Entity Address, Address Line Two Common stock issued and exercise of stock options (in shares) Stock Issued During Period, Shares, New Issues And Stock Options Exercised Stock Issued During Period, Shares, New Issues And Stock Options Exercised Net income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Common Stock Outstanding [Table] Common Stock Outstanding [Table] Common Stock Outstanding [Table] Current assets: Assets, Current [Abstract] Weighted-average remaining lease term (years) Operating Lease, Weighted Average Remaining Lease Term Non-PEO NEO Non-PEO NEO [Member] Senior Notes Senior Notes [Member] Entity Address, Address Line One Entity Address, Address Line One Right of use assets obtained for new operating lease liabilities Right-of-Use Asset Obtained in Exchange for Operating Lease Liability Provision for income taxes Income Tax Expense (Benefit) Customer Concentration Risk Customer Concentration Risk [Member] Award Timing Method Award Timing Method [Text Block] Net increase (decrease) in cash, cash equivalents and restricted cash 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] RECENT ACCOUNTING PRONOUNCEMENTS Accounting Standards Update and Change in Accounting Principle [Text Block] Net income Net income Net income Net Income (Loss) Attributable to Parent Long-Term Debt, Type Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Balance Sheet Location Location, Statement of Financial Position, Balance [Axis] Statement [Table] Statement [Table] Restatement Determination Date: Restatement Determination Date [Axis] Proceeds from exercise of stock options Proceeds from Stock Options Exercised Schedule of Remaining Performance Obligations Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] Interest income Investment Income, Interest Revenue Recognition [Line Items] Revenue Recognition [Line Items] Revenue recognition. 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