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Loans - Additional Information (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2024 USD ($) | Jun. 30, 2023 USD ($) | Jun. 30, 2024 USD ($) segment | Jun. 30, 2023 USD ($) | 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 |  | $ 2,200
Net loans held for investment | 301,537 |  | 301,537 |  | 305,176
Federal Home Loan banks |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Net loans held for investment | 7,300 |  | 7,300 |  | 7,400
Remaining borrowing capacity | 36,900 |  | 36,900 |  | 32,100
Federal Reserve Discount Window |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Line Items] |  |  |  |  |
Net loans held for investment | 83,300 |  | 83,300 |  | 78,300
Remaining borrowing capacity | 41,100 |  | 41,100 |  | $ 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 | $ 205 | $ 159 | $ 321 | $ 342 |

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