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INVESTMENT SECURITIES - Narrative (Details) shares in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2024 USD ($) security shares | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Jan. 24, 2024 USD ($) shares
Schedule of Investments [Line Items] |  |  |  |
Debt securities, available-for-sale, accrued Interest | $ 177,000,000 | $ 87,000,000 |  |
Debt Securities, held-to-maturity, accrued interest | 20,000,000 | 18,000,000 |  |
Write off of accrued interest receivable | $ 0 | 0 |  |
Debt securities, held-to-maturity, threshold period past due | 30 days |  |  |
Securities past due | $ 10,239,000,000 | 9,979,000,000 |  |
Realized gains on marketable equity securities sold | $ 6,000,000 | 0 | $ 0 |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 486 |  |  |
Investment securities available for sale, allowance for credit loss | $ 0 |  |  |
Securities, nonaccrual | 0 | 0 |  |
Total Past Due |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Securities past due | 0 | 0 |  |
Asset Pledged as Collateral |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investment securities, aggregate carrying value, pledged as collateral | $ 3,940,000,000 | $ 3,770,000,000 |  |
Visa, Inc | Class B |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investment owned (in shares) | shares | 354 |  |  |
Investment owned, carrying value | $ 0 |  |  |
Visa, Inc | Class B-1 |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Investment owned (in shares) | shares |  |  |  | 354
Investment owned, carrying value |  |  |  | $ 0
Government sponsored enterprise-issued mortgage-backed securities, government agency securities, or U.S. treasury securities |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 420 |  |  |
Corporate bonds |  |  |  |
Schedule of Investments [Line Items] |  |  |  |
Available-for-sale securities, continuous unrealized loss position, 12 months or longer, number of positions | security | 66 |  |  |

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