RESERVE FOR LOSSES AND LAE - Narrative (Details) - USD ($) $ in Millions |
6 Months Ended | |
|---|---|---|
Jun. 30, 2025 |
Jun. 30, 2024 |
|
| Reserves For Losses And LAE [Line Items] | ||
| Current year incurred losses | $ 3,375 | $ 2,801 |
| Prior year incurred net favorable development | (25) | $ 20 |
| War In Ukraine | ||
| Reserves For Losses And LAE [Line Items] | ||
| Current year incurred losses | 44 | |
| Current year incurred losses, gross | 57 | |
| Release Of Underwriting Reserves | ||
| Reserves For Losses And LAE [Line Items] | ||
| Prior year incurred net favorable development | (33) | |
| Aviation Losses | ||
| Reserves For Losses And LAE [Line Items] | ||
| Prior year incurred net favorable development | (57) | |
| Higher Premiums Earned | ||
| Reserves For Losses And LAE [Line Items] | ||
| Increase (decrease) in earned premium growth | 189 | |
| Catastrophe Losses | ||
| Reserves For Losses And LAE [Line Items] | ||
| Increase (decrease) in earned premium growth | $ 385 | |