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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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Percentage of decrease in weighted average contractual interest rate of financing receivable modified for debtor experiencing financial difficulty.

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Period of increase in weighted average maturity of financing receivable modified for debtor experiencing financial difficulty, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Loans - TDR Disclosure - Financial Effects of Financial Difficulty Modifications to Borrowers (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		$ 495		$ 1,629
Credit Card:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		106		289
Credit Card: \| Domestic Card \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average interest rate reduction	19.40%		19.19%
Credit Card: \| Domestic Card \| Principal Forgiveness [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction	$ 0		$ 0
Credit Card: \| Domestic Card \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Payment delay duration (in months)	12 months		12 months
Credit Card: \| International card businesses \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average interest rate reduction	27.41%		27.08%
Credit Card: \| International card businesses \| Principal Forgiveness [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction	$ 0		$ 0
Credit Card: \| International card businesses \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Payment delay duration (in months)	0 months		0 months
Consumer Banking:
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		276		796
Consumer Banking: \| Auto
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		275		794
Consumer Banking: \| Auto \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average interest rate reduction	8.67%		8.74%
Consumer Banking: \| Auto \| Principal Forgiveness [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction	$ 0		$ 1
Consumer Banking: \| Auto \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Payment delay duration (in months)	6 months		6 months
Consumer Banking: \| Retail banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		1		2
Consumer Banking: \| Retail banking \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average interest rate reduction	0.00%		2.00%
Consumer Banking: \| Retail banking \| Principal Forgiveness [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction	$ 0		$ 0
Consumer Banking: \| Retail banking \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Payment delay duration (in months)	8 months		13 months
Commercial Portfolio
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		113		544
Commercial Portfolio \| Commercial and multifamily real estate
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		38		302
Commercial Portfolio \| Commercial and multifamily real estate \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average interest rate reduction	0.00%		0.00%
Commercial Portfolio \| Commercial and multifamily real estate \| Principal Forgiveness [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction	$ 0		$ 20
Commercial Portfolio \| Commercial and multifamily real estate \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Payment delay duration (in months)	11 months		15 months
Commercial Portfolio \| Commercial and industrial
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction		$ 75		$ 242
Commercial Portfolio \| Commercial and industrial \| Interest Rate Reduction
Financing Receivable, Troubled Debt Restructuring [Line Items]
Weighted-average interest rate reduction	0.25%		0.25%
Commercial Portfolio \| Commercial and industrial \| Principal Forgiveness [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Principal balance reduction	$ 0		$ 3
Commercial Portfolio \| Commercial and industrial \| Term Extension
Financing Receivable, Troubled Debt Restructuring [Line Items]
Payment delay duration (in months)	17 months		9 months