Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	$ 3,807	$ 3,554
Nonperforming Loans	1,995	1,528
Nonperforming Loans Without an Allowance	$ 846	$ 547
Percentage, 90 Days Past Due and Accruing	1.16%	1.11%
Percentage, Nonperforming Loans	0.61%	0.48%
Percentage, Nonperforming Loans Without an Allowance	0.26%	0.17%
Interest income for loans classified as nonperforming	$ 111	$ 91
Credit Card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,711	3,499
Nonperforming Loans	10	9
Nonperforming Loans Without an Allowance	0	0
Credit Card: \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	3,577	3,367
Nonperforming Loans Without an Allowance	0	0
Credit Card: \| International card businesses:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	134	132
Nonperforming Loans	10	9
Nonperforming Loans Without an Allowance	0	0
Consumer Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	775	758
Nonperforming Loans Without an Allowance	12	19
Consumer Banking: \| Auto
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	750	712
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	25	46
Nonperforming Loans Without an Allowance	12	19
Commercial Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	96	55
Nonperforming Loans	1,210	761
Nonperforming Loans Without an Allowance	834	528
Commercial Banking: \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	509	425
Nonperforming Loans Without an Allowance	227	335
Commercial Banking: \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	96	55
Nonperforming Loans	701	336
Nonperforming Loans Without an Allowance	$ 607	$ 193

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.

+ References

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- Definition

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

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- Definition

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

+ References

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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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