v3.25.1
Cover - USD ($)
 12 Months Ended
Dec. 31, 2024
Apr. 25, 2025
Jun. 30, 2024
Document Information [Line Items]      
Document Type 10-K/A    
Document Annual Report true    
Document Period End Date Dec. 31, 2024    
Current Fiscal Year End Date --12-31    
Document Transition Report false    
Entity File Number 1-38300    
Entity Registrant Name CANNAE HOLDINGS, INC.    
Entity Incorporation, State or Country Code NV    
Entity Tax Identification Number 82-1273460    
Entity Address, Address Line One 1701 Village Center Circle    
Entity Address, City or Town Las Vegas    
Entity Address, State or Province NV    
Entity Address, Postal Zip Code 89134    
City Area Code 702    
Local Phone Number 323-7330    
Title of 12(b) Security Cannae Common Stock, $0.0001 par value    
Trading Symbol CNNE    
Security Exchange Name NYSE    
Entity Well-known Seasoned Issuer Yes    
Amendment Description EXPLANATORY NOTE This Amendment No. 1 (the “Amendment”) on Form 10-K/A is being filed with respect to the Registrant’s Annual Report on Form 10-K for the fiscal year ended December 31, 2024 filed with the Securities and Exchange Commission on February 27, 2025 (the “Form 10-K”). This Amendment updates Part III in its entirety to contain the information required therein. Except for the changes to Part III and the filing of related certifications added to the list of Exhibits in Part IV, this Amendment makes no changes to the Form 10-K. This Amendment does not reflect events occurring after the filing of the Form 10-K or modify disclosures affected by subsequent events.    
Entity Current Reporting Status Yes    
Entity Interactive Data Current Yes    
Entity Filer Category Large Accelerated Filer    
Entity Small Business false    
Entity Emerging Growth Company false    
ICFR Auditor Attestation Flag true    
Document Financial Statement Error Correction [Flag] false    
Entity Shell Company false    
Entity Public Float     $ 1,014,218,592
Entity Common Stock, Shares Outstanding   62,818,001  
Amendment Flag true    
Document Fiscal Year Focus 2024    
Document Fiscal Period Focus FY    
Entity Central Index Key 0001704720