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Allowance for Credit Losses and Reserve for Unfunded Lending Commitments - Additional Information (Details) - USD ($) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Uncollectible portion of billed finance charges and fees | $ 1,900 | $ 946 | $ 629 |
Allowance for credit loss | 15,296 | 13,240 |  |
Allowance for credit losses |  |  |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |  |
Increase (decrease) in allowance for credit loss | 2,100 |  |  |
Allowance for credit loss | $ 15,296 | $ 13,240 | $ 11,430 | $ 15,564

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- Definition Increase (Decrease) in Allowance for Credit Loss + References No definition available. + Details
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- Definition Uncollectible Portion of Billed Finance Charges and Fees + References No definition available. + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 326 -SubTopic 20 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479344/326-20-45-1 + Details
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- Details
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