Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2025	Mar. 31, 2024	Dec. 31, 2024
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	$ 3,365		$ 3,807
Nonperforming Loans	1,817		1,995
Nonperforming Loans Without an Allowance	$ 563		$ 846
Percentage, 90 Days Past Due and Accruing	1.04%		1.16%
Percentage, Nonperforming Loans	0.56%		0.61%
Percentage, Nonperforming Loans Without an Allowance	0.17%		0.26%
Interest income for loans classified as nonperforming	$ 3	$ 5
Credit Card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,365		$ 3,711
Nonperforming Loans	9		10
Nonperforming Loans Without an Allowance	0		0
Credit Card: \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,224		3,577
Nonperforming Loans Without an Allowance	0		0
Credit Card: \| International card businesses:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	141		134
Nonperforming Loans	9		10
Nonperforming Loans Without an Allowance	0		0
Consumer Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	584		775
Nonperforming Loans Without an Allowance	10		12
Consumer Banking: \| Auto
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	561		750
Nonperforming Loans Without an Allowance	0		0
Consumer Banking: \| Retail banking
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	23		25
Nonperforming Loans Without an Allowance	10		12
Commercial Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		96
Nonperforming Loans	1,224		1,210
Nonperforming Loans Without an Allowance	553		834
Commercial Banking: \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		0
Nonperforming Loans	393		509
Nonperforming Loans Without an Allowance	240		227
Commercial Banking: \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0		96
Nonperforming Loans	831		701
Nonperforming Loans Without an Allowance	$ 313		$ 607

Financing Receivable, Nonaccrual, No Allowance, Percent Past Due

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- Definition

Financing Receivable, Percent 90 Days Past Due and Still Accruing

+ References

No definition available.

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- Definition

Amount of interest income on financing receivable on nonaccrual status.

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Amortized cost of financing receivable on nonaccrual status with no allowance for credit loss. Excludes net investment in lease.

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Percentage of nonaccrual financing receivable balance outstanding that is past due.

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Amortized cost of financing receivable 90 days or more past due and still accruing. Excludes net investment in lease.

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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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