Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	Mar. 31, 2026	Dec. 31, 2025
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	$ 4,962	$ 5,352
Nonperforming Loans	1,785	1,819
Nonperforming Loans Without an Allowance	$ 710	$ 722
Percentage, 90 Days Past Due and Accruing	1.11%	1.18%
Percentage, Nonperforming Loans	0.40%	0.40%
Percentage, Nonperforming Loans Without an Allowance	0.16%	0.16%
Credit Card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	$ 4,962	$ 5,352
Nonperforming Loans	23	24
Nonperforming Loans Without an Allowance	0	0
Credit Card: \| Personal loans
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	44	47
Nonperforming Loans	12	12
Nonperforming Loans Without an Allowance	0	0
Credit Card: \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	4,757	5,148
Nonperforming Loans Without an Allowance	0	0
Credit Card: \| International card businesses:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	161	157
Nonperforming Loans	11	12
Nonperforming Loans Without an Allowance	0	0
Consumer Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	494	583
Nonperforming Loans Without an Allowance	9	4
Consumer Banking: \| Auto
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	475	566
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	19	17
Nonperforming Loans Without an Allowance	9	4
Commercial Banking:
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	1,268	1,212
Nonperforming Loans Without an Allowance	701	718
Commercial Banking: \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	362	320
Nonperforming Loans Without an Allowance	174	191
Commercial Banking: \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
> 90 Days and Accruing	0	0
Nonperforming Loans	906	892
Nonperforming Loans Without an Allowance	$ 527	$ 527

Financing Receivable, Nonaccrual, No Allowance, Percent Past Due

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Financing Receivable, Percent 90 Days Past Due and Still Accruing

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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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