v3.25.4
Income Taxes - Schedule of Effective Income Tax Reconciliation (Detail) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
(Loss) income before income taxes $ (21.6) $ 7.5 $ (2.9)
U.S. statutory tax rate 21.00% 21.00% 21.00%
Taxes at the U.S. statutory rate $ (4.6) $ 1.6 $ (0.6)
State and local taxes, net of federal benefit 1.1 0.5 0.8
Effect of cross-border tax laws: Global intangible income inclusion 2.6    
Share-based payments   4.6 0.3
Change in valuation allowance (6.0) (2.4) 3.7
Nontaxable or nondeductible items: Stock-based compensation 2.9    
Nontaxable or nondeductible items: Other (0.2)    
Return to provision adjustments   0.9 0.3
Change in tax rates   (0.6) 0.5
Changes in unrecognized tax benefits 0.3    
Nondeductible expenses   0.7 0.4
Other, net 0.3 0.0 (0.1)
Total provision for income taxes $ 9.1 $ 5.3 $ 5.3
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
U.S. Corporate federal income tax rate 21.00% 21.00% 21.00%
State and local income taxes, net of federal benefit, percent (5.10%)    
Effect of cross-border tax laws: Global intangible income inclusion, percent (12.00%)    
Changes in valuation allowances, percent 27.80%    
Nontaxable or nondeductible items: Stock-based compensation, percent (13.40%)    
Nontaxable or nondeductible items: Other, percent 0.90%    
Changes in unrecognized tax benefits, percent (1.40%)    
Other adjustments, percent (1.40%)    
Total tax provision and effective tax rate, percent (42.10%)    
Non-U.S Jurisdictions [Member] | United Kingdom [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ (0.9)    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent 4.20%    
Non-U.S Jurisdictions [Member] | United Kingdom [Member] | Changes in Valuation Allowance [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ 1.1    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent (5.10%)    
Non-U.S Jurisdictions [Member] | United Kingdom [Member] | Nontaxable or Nondeductible Items, Transaction Costs and Contingent Consideration [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ 9.1    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent (42.00%)    
Non-U.S Jurisdictions [Member] | United Kingdom [Member] | RTP Net Operating Loss [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ (0.3)    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent 1.40%    
Non-U.S Jurisdictions [Member] | Canada [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ (0.4)    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent 1.90%    
Non-U.S Jurisdictions [Member] | Canada [Member] | Provincial Tax [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ 1.5    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent (6.90%)    
Non-U.S Jurisdictions [Member] | Canada [Member] | Nontaxable or Nondeductible Items, Transaction Costs and Contingent Consideration [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ 2.3    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent (10.60%)    
Other Non-U.S Jurisdictions [Member] | United Kingdom [Member]      
Income Tax Expense (Benefit), Effective Income Tax Rate Reconciliation, Amount [Abstract]      
Foreign tax effects $ 0.3    
Effective Income Tax Rate Reconciliation, Percent [Abstract]      
Foreign tax effects, percent (1.40%)