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Loans - Additional Information (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2024 USD ($) segment | Mar. 31, 2023 USD ($) | Dec. 31, 2023 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Number of portfolio segments | segment | 3 |  |
Accrued interest receivable | $ 2,200 |  | $ 2,200
Net loans held for investment | 299,774 |  | 305,176
Federal Home Loan banks |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Net loans held for investment | 7,400 |  | 7,400
Remaining borrowing capacity | 36,700 |  | 32,100
Federal Reserve Discount Window |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Net loans held for investment | 74,100 |  | 78,300
Remaining borrowing capacity | 38,800 |  | $ 41,400
Domestic credit card: | Domestic Credit Card and Commercial Banking Portfolios |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |
Revolving loans converted to term during period | $ 116 | $ 183 |

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