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JANA Equity Components [Axis] Equity Components [Axis] Other operating expenses, including asset impairments Other Cost and Expense, Operating 2027 Recorded Unconditional Purchase Obligation, to be Paid, Year One Related Party Related Party [Member] Product and Service [Domain] Product and Service [Domain] Income taxes, net of refunds Income Tax Paid, after Refund Received Disaggregation of Revenue [Table] Disaggregation of Revenue [Table] Entity Interactive Data Current Entity Interactive Data Current Less: Net loss attributable to noncontrolling interests Losses of unconsolidated affiliates Net income attributable to noncontrolling interest Net Income (Loss) Attributable to Noncontrolling Interest Variable Interest Entity [Line Items] Variable Interest Entity [Line Items] Deferred tax liability Deferred Income Tax Liabilities, Net Compensation Actually Paid vs. Other Measure Compensation Actually Paid vs. Other Measure [Text Block] Accounts payable and other accrued liabilities, 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Combination, Recognized Asset Acquired, Identifiable Intangible Asset, Finite-Lived Discontinued Operations Assets Held for Sale Disposal Groups, Including Discontinued Operations, Disclosure [Text Block] 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] Document Type Document Type Consideration transferred for acquisition of Exeter Rugby Group Payments to Acquire Businesses, Net of Cash Acquired Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Tax (benefit) expense OCI, Equity Method Investment, Tax Fair Value as of Grant Date Award Grant Date Fair Value Collateral Pledged Collateral Pledged [Member] Intercompany Note Intercompany Note [Member] Intercompany Note Goodwill [Table] Goodwill [Table] Pay vs Performance Disclosure, Table Pay vs Performance [Table Text Block] Deferred revenue Business Combination, Recognized Liability Assumed, Deferred Revenue, Current Thereafter Long-Term Debt, Maturity, after Year Four Long-Term Debt, Maturity, after Year Four Arrangement Duration Trading Arrangement Duration Statement of Stockholders' Equity [Abstract] Statement of Stockholders' Equity [Abstract] Borrowings Proceeds from Issuance of Long-Term Debt Local Phone Number Local Phone Number Consolidation Items [Axis] Consolidation Items [Axis] Entity Address, Postal Zip Code Entity Address, Postal Zip Code Entity Registrant Name Entity Registrant Name Basis of Financial Statements Organization, Consolidation, Basis of Presentation, Business Description and Accounting Policies [Text Block] Loss before 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] Lease liabilities Increase (Decrease) In Lease Liabilities Increase (Decrease) In Lease Liabilities Commitments and contingencies - see Note H Commitments and Contingencies Total revenues Total revenues Total revenues Revenues Option Indexed to Issuer's Equity, Type [Domain] Option Indexed to Issuer's Equity, Type [Domain] Changed Peer Group, Footnote Changed Peer Group, Footnote [Text Block] Equity in income (losses) of unconsolidated affiliates Equity in losses of unconsolidated affiliates Equity in (loss) earnings of unconsolidated affiliates Equity in losses of unconsolidated affiliates Income (Loss) from Equity Method Investments Forgone Recovery due to Expense of Enforcement, Amount Forgone Recovery due to Expense of Enforcement, Amount Executive Category: Executive Category [Axis] LIABILITIES AND EQUITY Liabilities and Equity [Abstract] Intangible Asset, Finite-Lived, Class [Domain] Intangible Asset, Finite-Lived, Class [Domain] Other Commitments [Table] Other Commitments [Table] Schedule of Fair Value of Assets and Liabilities Measured at Fair Value on a Recurring Basis Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block] All Award Types Award Type [Domain] Number of loans that can be made Number Of Loans Available, Minimum Number Of Loans Available, Minimum Non-PEO NEO Average Compensation Actually Paid Amount Non-PEO NEO Average Compensation Actually Paid Amount O'Charley's O'Charley's [Member] O'Charley's Fair Value Measurements Fair Value Disclosures [Text Block] Variable Interest Entity [Table] Variable Interest Entity [Table] Level 3 Fair Value, Inputs, Level 3 [Member] Cash paid during the period: Supplemental Cash Flow Information [Abstract] Treasury stock repurchases (in shares) Treasury Stock, Shares, Acquired PEO Name PEO Name Loss from discontinued operations before income taxes Discontinued Operation, Income (Loss) from Discontinued Operation, before Income Tax Exeter Rugby Group Exeter Rugby Group [Member] Exeter Rugby Group Deferred revenue (contract liabilities) Contract with Customer, Liability Liabilities: Financial Instruments, Financial Liabilities, Balance Sheet Groupings [Abstract] Other segment items Segment Reporting, Other Segment Item, Amount Consideration transferred, equity interest, share issued Business Combination, Consideration Transferred, Equity Interest, Share Issued, Value FNF Revolver Corporate Revolver Note [Member] Corporate Revolver Note [Member] Stock Price or TSR Estimation Method Stock Price or TSR Estimation Method [Text Block] Entity Tax Identification Number Entity Tax Identification Number Legal Entity [Axis] Legal Entity [Axis] Termination Fees Expense Termination Fees Expenses [Member] Termination Fees Expenses Other Commitments [Line Items] Other Commitments [Line Items] Treasury stock repurchases Stock repurchases cost Treasury Stock, Value, Acquired, Cost Method Cash and cash equivalents at beginning of period Cash and cash equivalents at end of period Cash, Cash Equivalent, Restricted Cash, and Restricted Cash Equivalent, Continuing Operation Entity Incorporation, State or Country Code Entity Incorporation, State or Country Code Net loss from discontinued operations - see Note J Income (Loss) From Equity Method Investment, Discontinued Operations Income (Loss) From Equity Method Investment, Discontinued Operations 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] 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] Net loss per share from discontinued operations (in usd per share) Income (Loss) from Discontinued Operations and Disposal of Discontinued Operations, Net of Tax, Per Basic Share Comprehensive earnings (loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Debt Instrument [Axis] Debt Instrument [Axis] Other liabilities Business Combination, Recognized Liability Assumed, Other Liability, Noncurrent Reporting Unit [Domain] Reporting Unit [Domain] Ownership percentage Equity Method Investment, Ownership Percentage Payments to acquire businesses, gross Payments to Acquire Businesses, Gross Stock-based compensation expense Share-Based Payment Arrangement, Noncash Expense Total accounts payable and other accrued liabilities, current Accounts Payable and Accrued Liabilities, Fair Value Disclosure Personnel costs Labor and Related Expense Black Knight Rugby, LLC Black Knight Rugby, LLC [Member] Black Knight Rugby, LLC Disposal Group Name [Axis] Disposal Group Name [Axis] Investment, Name [Domain] Investment, Name [Domain] 2027 Long-Term Debt, Maturity, Year One Long-term Debt, Type [Domain] Long-Term Debt, Type [Domain] Net income (loss) per share (in usd per share) Net loss per share (in usd per share) Earnings Per Share, Basic Treasury stock repurchases Payments for Repurchase of Common Stock Deferred revenue Contract with Customer, Liability, Current Total current assets Assets, Current Insider Trading Arrangements [Line Items] Notes payable, long-term Notes payable, long term Long-Term Debt, Excluding Current Maturities Award Type Award Type [Axis] Named Executive Officers, Footnote Named Executive Officers, Footnote [Text Block] Retained earnings Retained earnings Retained Earnings (Accumulated Deficit) Product and Service [Axis] Product and Service [Axis] Reclassification adjustments for unrealized gains and losses on unconsolidated affiliates, net of tax, included in net earnings, tax expense Other Comprehensive Income Loss Reclassification Adjustment For Net Unrealized Gains Losses On Unconsolidated Affiliates, Net Of Tax, Include Net Earnings. Tax Other Comprehensive Income Loss Reclassification Adjustment For Net Unrealized Gains Losses On Unconsolidated Affiliates, Net Of Tax, Include Net Earnings. Tax 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] Fair Value Measurement [Domain] Fair Value Measurement [Domain] Compensation Actually Paid vs. Company Selected Measure Compensation Actually Paid vs. Company Selected Measure [Text Block] Cover [Abstract] Cover [Abstract] Unconsolidated affiliates Equity Method Investment, Nonconsolidated Investee or Group of Investees [Member] Derivative Contract [Domain] Derivative Contract [Domain] Ownership interest disposed (as a percent) Disposal Group, Including Discontinued Operation, Ownership Interest Disposed Disposal Group, Including Discontinued Operation, Ownership Interest Disposed Equity Awards Adjustments Equity Awards Adjustments [Member] Total liabilities and equity Liabilities and Equity Employee Stock Option Share-Based Payment Arrangement, Option [Member] Noncontrolling interests Equity, Attributable to Noncontrolling Interest Notes Payable Notes Payable, Other Payables [Member] Segments [Axis] Segments [Axis] Additional 402(v) Disclosure Additional 402(v) Disclosure [Text Block] Asset Class [Axis] Asset Class [Axis] Related Party [Domain] Related and Nonrelated Parties [Domain] Tabular List, Table Tabular List [Table Text Block] Additional paid-in capital Additional Paid in Capital Equity securities, at fair value Equity securities Equity Securities, FV-NI, Noncurrent Other Other Products And Services [Member] Other Products And Services [Member] Income taxes receivable Income taxes receivable Income Taxes Receivable, Current Name Awards Close in Time to MNPI Disclosures, Individual Name Equity: Equity, Including Portion Attributable to Noncontrolling Interest [Abstract] 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] Management Fees Expense Management Fees Expense [Member] Management Fee Expense Preferred stock authorized (in shares) Preferred Stock, Shares Authorized AmeriLife and Other AmeriLife and Other [Member] AmeriLife and Other Preferred stock, 0.0001 par value; authorized 10,000,000 shares; none issued and outstanding as of June 30, 2026 and December 31, 2025 Preferred Stock, Value, Issued Vesting of shares held in trust (in shares) Share-Based Compensation Arrangement, Shares Vested, Held In Trust, Shares Share-Based Compensation Arrangement, Shares Vested, Held In Trust, Shares Adjustment to Compensation: Adjustment to Compensation [Axis] Share Repurchase Program [Axis] Share Repurchase Program [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 Interest Interest Paid, Excluding Capitalized Interest, Operating Activity Additions to property and equipment and other intangible assets Payments to Acquire Productive Assets Statement of Cash Flows [Abstract] Statement of Cash Flows [Abstract] Credit Facility [Axis] Credit Facility [Axis] Aggregate Available Trading Arrangement, Securities Aggregate Available Amount Total assets Assets, Fair Value Disclosure Discontinued Operations and Disposal Groups [Abstract] Discontinued Operations and Disposal Groups [Abstract] Name Measure Name Other Other Notes Payable [Member] Other Notes Payable [Member] Pay vs Performance Disclosure [Line Items] Fair Value Hierarchy and NAV [Domain] Fair Value Hierarchy and NAV [Domain] Debt Instrument [Line Items] Debt Instrument [Line Items] Pay vs Performance Disclosure Pay vs Performance Disclosure [Table] Corporate and Other Corporate and other Corporate Segment and Other Operating Segment [Member] Consideration transferred Business Combination, Consideration Transferred Additional Paid-in Capital Additional Paid-in Capital [Member] Entity Filer Category Entity Filer Category Supplemental Cash Flow Elements [Abstract] Supplemental Cash Flow Elements [Abstract] Goodwill impairment Goodwill, Impairment Loss Number of restaurants Number of Restaurants Reclassification adjustments for unrealized gains and losses of unconsolidated affiliates, net of tax, included in net earnings Reclassification adjustments for unrealized gains and losses on unconsolidated affiliates, net of tax, included in net earnings Other Comprehensive Income Loss Reclassification Adjustment For Net Unrealized Gains Losses On Unconsolidated Affiliates, Net Of Tax, Include Net Earnings Other Comprehensive Income Loss Reclassification Adjustment For Net Unrealized Gains Losses On Unconsolidated Affiliates, Net Of Tax, Include Net Earnings Restatement [Axis] Revision of Prior Period [Axis] Name Trading Arrangement, Individual Name Cash and cash equivalents Cash and Cash Equivalent 2027 Bond Matures On November 30, 2027 2027 Bond Matures On November 30, 2027 [Member] 2027 Bond Matures On November 30, 2027 Company Selected Measure Amount Company Selected Measure Amount Distributions from investments in unconsolidated affiliates Dividends received Proceeds from Equity Method Investment, Distribution Less: net gains (losses) recognized during the period on equity securities sold, transferred or disposed during the period Equity Securities, FV-NI, Unrealized Gain (Loss) Investments, Debt and Equity Securities [Abstract] Investments, Debt and Equity Securities [Abstract] Depreciation and amortization Depreciation and amortization Depreciation and amortization Depreciation, Depletion and Amortization Schedule of Gains (Losses) on Securities Gain (Loss) on Securities [Table Text Block] Net income (loss) from continuing operations attributable to Cannae Holdings, Inc. common shareholders Net Income (Loss) from Continuing Operations Available to Common Shareholders, Basic Net income (loss) Net income (loss) Net income (loss) attributable to BKFC Net loss Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Current assets: Assets, Current [Abstract] Put Right Derivative Liability Non-PEO NEO Non-PEO NEO [Member] Entity Address, Address Line One Entity Address, Address Line One Settlement amount Option Contract Indexed to Equity, Settlement, Cash, Amount Proceeds from sale and maturity of short-term investment securities Proceeds from Sale, Maturity and Collection of Short-Term Investments Income tax expense (benefit) Income tax expense Income Tax Expense (Benefit) 2020 Margin Facility 2020 Margin Facility [Member] 2020 Margin Facility Temporary Equity, by Class of Stock [Table] Temporary Equity, by Class of Stock [Table] Cost of restaurant revenue Cost of revenue Cost of Product and Service Sold Award Timing Method Award Timing Method [Text Block] Principles of Consolidation Consolidation, Policy [Policy Text Block] Net decrease in cash and 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] Deferred tax liability Business Combination, Recognized Liability Assumed, Deferred Tax Liability Shares held and subject to put right, percentage Common Stock, Shares Held And Subject To Put Right, Percentage Common Stock, Shares Held And Subject To Put Right, Percentage 99 Restaurants 99 Restaurants [Member] 99 Restaurants Net income (loss) attributable to Cannae Holdings, Inc. common shareholders Net loss attributable to Cannae Holdings, Inc. common shareholders Net loss attributable to D&B Net Income (Loss) Attributable to Parent Long-term Debt, Type [Axis] Long-Term Debt, Type [Axis] Erroneous Compensation Analysis Erroneous Compensation Analysis [Text Block] Proceeds from sales of property and equipment Proceeds from Sale of Property, Plant, and Equipment Net loss from discontinued operations, net of tax - see Note J Net loss from discontinued operations Net loss from discontinued operations, net of tax Income (Loss) from Discontinued Operations, Net of Tax, Including Portion Attributable to Noncontrolling Interest Statement [Table] Statement [Table] Repurchase in excess of trading price, percentage Option Indexed to Issuer's Equity, Repurchase In Excess Of Trading Price, Percentage Option Indexed to Issuer's Equity, Repurchase In Excess Of Trading Price, Percentage Restaurant revenue Restaurant sales Restaurant Sales [Member] Restaurant Sales [Member] Restatement Determination Date: Restatement Determination Date [Axis] Potential future payments Equity Method Investment, Contingent Consideration Liability Equity Method Investment, Contingent Consideration Liability Schedule of Contract Balances, Receivables and Deferred Revenue Contract with Customer, Contract Asset, Contract Liability, and Receivable [Table Text Block] Exeter Loan Exeter Loan [Member] Exeter Loan Revenues: Revenues [Abstract] Pension Benefits Adjustments, Footnote Pension Benefits Adjustments, Footnote [Text Block] Other operating revenue Total other operating revenue Other Operating Revenue [Member] Total Other Operating Revenue [Member]