Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022	Dec. 31, 2022
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 2,465		$ 2,240
Nonperforming Loans	1,306		1,344
Nonperforming Loans Without an Allowance	$ 492		$ 548
Percentage, 90 Days Past Due and Accruing	0.80%		0.72%
Percentage, Nonperforming Loans	0.42%		0.43%
Percentage, Nonperforming Loans Without an Allowance	0.16%		0.18%
Interest income for loans classified as nonperforming	$ 2	$ 1
Credit Card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	2,465		$ 2,240
Nonperforming Loans	7		9
Nonperforming Loans Without an Allowance	0		0
Credit Card \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	2,352		2,135
Nonperforming Loans Without an Allowance	0		0
Credit Card \| International card businesses:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	113		105
Nonperforming Loans	7		9
Nonperforming Loans Without an Allowance	0		0
Consumer Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0		0
Nonperforming Loans	559		634
Nonperforming Loans Without an Allowance	6		8
Consumer Banking \| Auto
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0		0
Nonperforming Loans	515		595
Nonperforming Loans Without an Allowance	0		0
Consumer Banking \| Retail banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0		0
Nonperforming Loans	44		39
Nonperforming Loans Without an Allowance	6		8
Commercial Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0		0
Nonperforming Loans	740		701
Nonperforming Loans Without an Allowance	486		540
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0		0
Nonperforming Loans	336		271
Nonperforming Loans Without an Allowance	255		246
Commercial Banking \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0		0
Nonperforming Loans	404		430
Nonperforming Loans Without an Allowance	$ 231		$ 294

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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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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- 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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