v3.26.1
Fair Value Measurements Fair Value Measurements (Reconciliation of Assets and Liabilities Measured at Fair Value on a Recurring Basis Using Significant Unobservable Inputs) (Details) - USD ($)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Jun. 30, 2026
Jun. 30, 2025
Mar. 31, 2026
Dec. 31, 2025
Mar. 31, 2025
Dec. 31, 2024
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]                
Investments, Fair Value Disclosure $ 821.4 $ 833.7 $ 821.4 $ 833.7   $ 844.0   $ 742.0
Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]                
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation [Line Items]                
Investments, Fair Value Disclosure 295.6 293.1 295.6 293.1 $ 305.7 $ 304.7 $ 311.0 $ 330.3
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]                
Business Combination, Contingent Consideration, Liability, Beginning Balance 17.7 37.5 17.2 35.8        
Derivative Assets (Liabilities), at Fair Value, Net, Beginning Balance 46.6 16.7 31.6 93.8        
Business Combination, Contingent Consideration, Liability, Ending Balance 17.0 19.1 17.0 19.1        
Derivative Assets (Liabilities), at Fair Value, Net, Ending Balance 25.8 19.9 25.8 19.9        
Earn-out Liabilities [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]                
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]                
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings 0.0 (7.4) 0.5 (3.5)        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) 0.0 0.3 0.0 0.4        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases 0.0 0.2 0.0 0.2        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements (0.7) (12.0) (0.7) (12.1)        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 0.0 0.5 0.0 (1.7)        
Derivative [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]                
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]                
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings 13.6 9.7 51.1 17.0        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) 0.0 0.0 0.0 0.0        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases 31.2 34.9 65.9 64.9        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements (65.6) (41.4) (122.8) (155.8)        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 0.0 0.0 0.0 0.0        
Investments [Member] | Fair Value, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]                
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]                
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Earnings (10.2) (25.3) (8.5) (45.2)        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included in Other Comprehensive Income (Loss) 0.1 1.4 (0.6) 2.1        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Purchases 0.0 6.0 0.0 6.0        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements 0.0 0.0 0.0 (0.1)        
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3 $ 0.0 $ 0.0 $ 0.0 $ 0.0