v3.25.4
Cash and Investments - Changes in Level 3 financial assets (Details) - USD ($)
$ in Millions
 12 Months Ended
Dec. 31, 2025
Dec. 31, 2024
Jan. 01, 2025
Blizzard Vacatia      
Changes in fair value measurement, assets      
Percentage of voting equity interests acquired     50.00%
Purchase consideration     $ 835.0
Liabilities incurred, senior secured loan     365.0
Equity interests of acquirer, preferred shares     275.0
Liabilities incurred, mortgage-backed loan     170.0
Equity interests of acquirer, common shares     $ 25.0
Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 $ 10,059.0 $ 11,460.0  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings 472.3 480.5  
Purchases 3,721.5 1,777.2  
Transfer into category 299.6    
Sales and distributions (2,547.4) (1,728.5)  
Transfer out of category   (1,816.1)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 122.8 (114.1)  
Deconsolidation of non-insurance subsidiary (13.1)    
Assets held for sale (130.7)    
Balance - December 31 11,984.0 10,059.0  
Private placement debt securities | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 5,762.6 5,797.0  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings (5.8) 29.4  
Purchases 3,181.2 1,306.3  
Sales and distributions (1,859.0) (1,280.3)  
Transfer out of category   (31.8)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 78.6 (58.0)  
Assets held for sale (107.2)    
Balance - December 31 7,050.4 5,762.6  
Net purchases of first mortgage loans 662.6 103.5  
Private company preferred shares | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 419.9 2,142.0  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings 25.6 57.8  
Purchases 11.5 12.7  
Transfer into category 299.6    
Sales and distributions (1.4) (1.4)  
Transfer out of category   (1,784.3)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 4.6 (6.9)  
Deconsolidation of non-insurance subsidiary (1.6)    
Balance - December 31 758.2 419.9  
Limited partnerships and other | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 2,104.8 1,998.2  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings 152.0 125.1  
Purchases 274.0 203.6  
Sales and distributions (262.8) (203.5)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 16.0 (18.6)  
Balance - December 31 2,284.0 2,104.8  
Private equity funds | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 70.9 72.8  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings 8.2 9.0  
Sales and distributions (14.6) (8.6)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 6.6 (2.3)  
Balance - December 31 71.1 70.9  
Common stocks | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 992.7 957.5  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings 41.4 80.4  
Purchases 83.8 160.6  
Sales and distributions (58.6) (191.7)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 10.0 (14.1)  
Deconsolidation of non-insurance subsidiary (11.5)    
Assets held for sale (23.5)    
Balance - December 31 1,034.3 992.7  
Derivatives | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 86.4 (84.5)  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings 259.0 207.2  
Purchases 39.7    
Sales and distributions (334.0) (35.7)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 0.1 (0.6)  
Balance - December 31 51.2 86.4  
Other invested assets | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - January 1 621.7 577.0  
Net realized and unrealized gains (losses) included in the consolidated statement of earnings (8.1) (28.4)  
Purchases 131.3 94.0  
Sales and distributions (17.0) (7.3)  
Unrealized foreign currency translation gains (losses) on foreign subsidiaries included in other comprehensive income (loss) 6.9 (13.6)  
Balance - December 31 734.8 $ 621.7  
Derivatives and other invested assets | Significant unobservable inputs (Level 3)      
Changes in fair value measurement, assets      
Balance - December 31 $ 734.8