INVESTMENT SECURITIES - Realized and Unrealized Gain (Loss) on Securities (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2026 |
Jun. 30, 2025 |
Jun. 30, 2026 |
Jun. 30, 2025 |
|
| Investments, Debt and Equity Securities [Abstract] | ||||
| Net unrealized gains (losses) for equity securities with readily determinable fair value (RDFV) | $ 67 | $ 5 | $ (245) | $ 10 |
| Proceeds from debt/equity securities sales and redemptions | 1,245 | 552 | 2,164 | 1,224 |
| Gross realized gains on debt securities | 25 | 5 | 31 | 10 |
| Gross realized losses and impairments on debt securities | $ (31) | $ (10) | $ (38) | $ (17) |