Card Balances and Other Loans - Aging (Details) - Card Balances - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Accounts, Notes, Loans and Financing Receivable [Line Items]
Threshold period past due	30 days
Financing receivables, gross	$ 213,311	$ 213,863
Loans and receivables threshold period for write off	180 days
Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	$ 140,908	144,324
Loans over 90 days past due and accruing interest	452	434
Non-accruals	480	471
Small Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	55,098	53,632
Loans over 90 days past due and accruing interest	136	130
Non-accruals	186	177
Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	17,306	15,907
Loans over 90 days past due and accruing interest	0	0
Non-accruals	0	0
Current \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	139,125	142,552
Current \| Small Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	54,295	52,870
30 to 59 Days Past Due \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	522	529
30 to 59 Days Past Due \| Small Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	256	255
60 to 89 Days Past Due \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	388	392
60 to 89 Days Past Due \| Small Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	194	168
90+ Days Past Due \| Consumer
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	873	851
90+ Days Past Due \| Small Business
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	353	340
90+ Days Past Due \| Corporate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivables, gross	$ 71	$ 75

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.

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