Investments in Associates - Balance sheet disclosures (Details) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
|---|---|---|---|
| As presented on the consolidated balance sheet: | |||
| Investments in associates, at fair value | $ 11,057.7 | $ 8,144.8 | |
| Fairfax India investments in associates, at fair value | 3,175.4 | 2,599.0 | |
| Total, Fair Value | 14,233.1 | 10,743.8 | |
| Associates and joint ventures | 8,362.3 | 7,153.3 | |
| Fairfax India associates | 1,615.3 | 1,352.3 | |
| Total | $ 9,977.6 | $ 8,505.6 | $ 8,037.3 |