INVESTMENTS - Equity Securities (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
|
| Investments, Debt and Equity Securities [Abstract] | ||||
| Net investment gains (losses) recognized during the period on securities held at the end of the period | $ 9 | $ 40 | $ 3 | $ 38 |
| Net investment gains (losses) recognized on securities sold during the period | (1) | (24) | 3 | (22) |
| Unrealized and realized gains (losses) on equity securities | $ 8 | $ 16 | $ 6 | $ 16 |