v3.25.4
Cash and Investments - Fair value hierarchy (Details) - USD ($)
$ in Millions
12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Dec. 31, 2023
Cash and Investments      
Derivative obligations $ (76,913.6) $ (68,428.1)  
Percentage of assets 100.00% 100.00%  
Investment in associates $ 11,057.7 $ 8,144.8  
Restricted cash and cash equivalents $ 644.6 $ 1,400.1  
Quoted prices (Level 1)      
Cash and Investments      
Percentage of assets 21.90% 20.10%  
Significant other observable inputs (Level 2)      
Cash and Investments      
Percentage of assets 59.70% 62.80%  
Significant unobservable inputs (Level 3)      
Cash and Investments      
Financial assets $ 11,984.0 $ 10,059.0 $ 11,460.0
Percentage of assets 18.40% 17.10%  
Investments in first mortgage loans secured by real estate $ 5,402.5 $ 4,777.8  
Significant unobservable inputs (Level 3) | Bonds      
Cash and Investments      
Financial assets 7,050.4    
Significant unobservable inputs (Level 3) | Common stocks      
Cash and Investments      
Financial assets 1,034.3 992.7 957.5
Significant unobservable inputs (Level 3) | Derivatives and other invested assets      
Cash and Investments      
Financial assets 734.8    
Significant unobservable inputs (Level 3) | Derivatives      
Cash and Investments      
Financial assets 51.2 86.4 (84.5)
Significant unobservable inputs (Level 3) | Other invested assets      
Cash and Investments      
Financial assets 734.8 621.7 $ 577.0
Recurring      
Cash and Investments      
Investment in associates 14,233.1 10,743.8  
Recurring | Holding company      
Cash and Investments      
Financial assets 64,882.2 58,860.6  
Recurring | Derivative obligations      
Cash and Investments      
Derivative obligations (786.9) (356.9)  
Recurring | Cash and cash equivalents      
Cash and Investments      
Financial assets 6,782.9 7,512.6  
Recurring | Short term investments      
Cash and Investments      
Financial assets 2,435.0 1,010.0  
Recurring | Short term investments, Canadian government and provincials      
Cash and Investments      
Financial assets 1,542.8 98.5  
Recurring | Short term investments, U.S. treasury      
Cash and Investments      
Financial assets 107.2 217.8  
Recurring | Short term investments, Other government      
Cash and Investments      
Financial assets 376.1 226.7  
Recurring | Short term investments, Corporate and other      
Cash and Investments      
Financial assets 408.9 467.0  
Recurring | Bonds      
Cash and Investments      
Financial assets 40,758.7 38,235.5  
Recurring | Bonds, Canadian government and provincials      
Cash and Investments      
Financial assets 2,609.8 2,741.0  
Recurring | Bonds, U.S. treasury      
Cash and Investments      
Financial assets 20,081.9 15,863.9  
Recurring | Bonds, U.S. states and municipalities      
Cash and Investments      
Financial assets 163.1 179.6  
Recurring | Bonds, Other government      
Cash and Investments      
Financial assets 6,081.5 6,133.3  
Recurring | Bonds, Corporate and other      
Cash and Investments      
Financial assets 11,822.4 13,317.7  
Recurring | Preferred stocks      
Cash and Investments      
Financial assets 2,320.1 2,385.2  
Recurring | Preferred stocks, Canadian      
Cash and Investments      
Financial assets 30.8 35.5  
Recurring | Preferred stocks, U.S.      
Cash and Investments      
Financial assets 444.9 398.9  
Recurring | Preferred stocks, Other      
Cash and Investments      
Financial assets 1,844.4 1,950.8  
Recurring | Common stocks      
Cash and Investments      
Financial assets 9,790.5 7,877.7  
Recurring | Common stocks, Canadian      
Cash and Investments      
Financial assets 2,084.7 1,772.3  
Recurring | Common stocks, U.S.      
Cash and Investments      
Financial assets 3,020.4 2,332.7  
Recurring | Common stocks, Other      
Cash and Investments      
Financial assets 4,685.4 3,772.7  
Recurring | Derivatives and other invested assets      
Cash and Investments      
Financial assets 3,581.9 2,196.5  
Recurring | Derivatives      
Cash and Investments      
Financial assets 2,847.1 1,574.8  
Recurring | Other invested assets      
Cash and Investments      
Financial assets 734.8 621.7  
Recurring | Quoted prices (Level 1)      
Cash and Investments      
Investment in associates 6,217.6 4,420.5  
Recurring | Quoted prices (Level 1) | Holding company      
Cash and Investments      
Financial assets 14,177.0 11,837.1  
Recurring | Quoted prices (Level 1) | Cash and cash equivalents      
Cash and Investments      
Financial assets 6,782.9 7,512.6  
Recurring | Quoted prices (Level 1) | Short term investments      
Cash and Investments      
Financial assets 1,743.6 372.0  
Recurring | Quoted prices (Level 1) | Short term investments, Canadian government and provincials      
Cash and Investments      
Financial assets 1,542.8 98.5  
Recurring | Quoted prices (Level 1) | Short term investments, U.S. treasury      
Cash and Investments      
Financial assets 107.2 217.8  
Recurring | Quoted prices (Level 1) | Short term investments, Other government      
Cash and Investments      
Financial assets 93.6 55.7  
Recurring | Quoted prices (Level 1) | Preferred stocks      
Cash and Investments      
Financial assets 34.9 28.6  
Recurring | Quoted prices (Level 1) | Preferred stocks, Canadian      
Cash and Investments      
Financial assets 18.7 16.3  
Recurring | Quoted prices (Level 1) | Preferred stocks, Other      
Cash and Investments      
Financial assets 16.2 12.3  
Recurring | Quoted prices (Level 1) | Common stocks      
Cash and Investments      
Financial assets 5,615.6 3,923.9  
Recurring | Quoted prices (Level 1) | Common stocks, Canadian      
Cash and Investments      
Financial assets 1,737.7 1,264.5  
Recurring | Quoted prices (Level 1) | Common stocks, U.S.      
Cash and Investments      
Financial assets 1,341.0 902.4  
Recurring | Quoted prices (Level 1) | Common stocks, Other      
Cash and Investments      
Financial assets 2,536.9 1,757.0  
Recurring | Significant other observable inputs (Level 2)      
Cash and Investments      
Investment in associates 735.8 679.5  
Recurring | Significant other observable inputs (Level 2) | Holding company      
Cash and Investments      
Financial assets 38,721.2 36,964.5  
Recurring | Significant other observable inputs (Level 2) | Derivative obligations      
Cash and Investments      
Derivative obligations (331.4) (222.7)  
Recurring | Significant other observable inputs (Level 2) | Short term investments      
Cash and Investments      
Financial assets 691.4 638.0  
Recurring | Significant other observable inputs (Level 2) | Short term investments, Other government      
Cash and Investments      
Financial assets 282.5 171.0  
Recurring | Significant other observable inputs (Level 2) | Short term investments, Corporate and other      
Cash and Investments      
Financial assets 408.9 467.0  
Recurring | Significant other observable inputs (Level 2) | Bonds      
Cash and Investments      
Financial assets 33,708.3 32,472.9  
Recurring | Significant other observable inputs (Level 2) | Bonds, Canadian government and provincials      
Cash and Investments      
Financial assets 2,609.8 2,741.0  
Recurring | Significant other observable inputs (Level 2) | Bonds, U.S. treasury      
Cash and Investments      
Financial assets 20,081.9 15,863.9  
Recurring | Significant other observable inputs (Level 2) | Bonds, U.S. states and municipalities      
Cash and Investments      
Financial assets 163.1 179.6  
Recurring | Significant other observable inputs (Level 2) | Bonds, Other government      
Cash and Investments      
Financial assets 6,027.5 6,087.4  
Recurring | Significant other observable inputs (Level 2) | Bonds, Corporate and other      
Cash and Investments      
Financial assets 4,826.0 7,601.0  
Recurring | Significant other observable inputs (Level 2) | Preferred stocks      
Cash and Investments      
Financial assets 1,527.0 1,936.7  
Recurring | Significant other observable inputs (Level 2) | Preferred stocks, Other      
Cash and Investments      
Financial assets 1,527.0 1,936.7  
Recurring | Significant other observable inputs (Level 2) | Common stocks      
Cash and Investments      
Financial assets 785.5 785.4  
Recurring | Significant other observable inputs (Level 2) | Common stocks, Canadian      
Cash and Investments      
Financial assets 101.3 175.4  
Recurring | Significant other observable inputs (Level 2) | Common stocks, U.S.      
Cash and Investments      
Financial assets 39.4 34.3  
Recurring | Significant other observable inputs (Level 2) | Common stocks, Other      
Cash and Investments      
Financial assets 644.8 575.7  
Recurring | Significant other observable inputs (Level 2) | Derivatives and other invested assets      
Cash and Investments      
Financial assets 2,340.4 1,354.2  
Recurring | Significant other observable inputs (Level 2) | Derivatives      
Cash and Investments      
Financial assets 2,340.4 1,354.2  
Recurring | Significant unobservable inputs (Level 3)      
Cash and Investments      
Investment in associates 7,279.7 5,643.8  
Recurring | Significant unobservable inputs (Level 3) | Holding company      
Cash and Investments      
Financial assets 11,984.0 10,059.0  
Recurring | Significant unobservable inputs (Level 3) | Derivative obligations      
Cash and Investments      
Derivative obligations (455.5) (134.2)  
Recurring | Significant unobservable inputs (Level 3) | Bonds      
Cash and Investments      
Financial assets 7,050.4 5,762.6  
Recurring | Significant unobservable inputs (Level 3) | Bonds, Other government      
Cash and Investments      
Financial assets 54.0 45.9  
Recurring | Significant unobservable inputs (Level 3) | Bonds, Corporate and other      
Cash and Investments      
Financial assets 6,996.4 5,716.7  
Recurring | Significant unobservable inputs (Level 3) | Preferred stocks      
Cash and Investments      
Financial assets 758.2 419.9  
Recurring | Significant unobservable inputs (Level 3) | Preferred stocks, Canadian      
Cash and Investments      
Financial assets 12.1 19.2  
Recurring | Significant unobservable inputs (Level 3) | Preferred stocks, U.S.      
Cash and Investments      
Financial assets 444.9 398.9  
Recurring | Significant unobservable inputs (Level 3) | Preferred stocks, Other      
Cash and Investments      
Financial assets 301.2 1.8  
Recurring | Significant unobservable inputs (Level 3) | Common stocks      
Cash and Investments      
Financial assets 3,389.4 3,168.4  
Recurring | Significant unobservable inputs (Level 3) | Common stocks, Canadian      
Cash and Investments      
Financial assets 245.7 332.4  
Recurring | Significant unobservable inputs (Level 3) | Common stocks, U.S.      
Cash and Investments      
Financial assets 1,640.0 1,396.0  
Recurring | Significant unobservable inputs (Level 3) | Common stocks, Other      
Cash and Investments      
Financial assets 1,503.7 1,440.0  
Recurring | Significant unobservable inputs (Level 3) | Derivatives and other invested assets      
Cash and Investments      
Financial assets 1,241.5 842.3  
Recurring | Significant unobservable inputs (Level 3) | Derivatives      
Cash and Investments      
Financial assets 506.7 220.6  
Recurring | Significant unobservable inputs (Level 3) | Other invested assets      
Cash and Investments      
Financial assets $ 734.8 $ 621.7  
Digit      
Cash and Investments      
Ownership percentage 49.00% 49.00%  
Blizzard Vacatia      
Cash and Investments      
Restricted cash held for purchase of associate   $ 835.0