Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 2,240	$ 1,195
Nonperforming Loans	1,344	1,100
Nonperforming Loans Without an Allowance	$ 548	$ 529
Percentage, 90 Days Past Due and Accruing	0.72%	0.43%
Percentage, Nonperforming Loans	0.43%	0.40%
Percentage, Nonperforming Loans Without an Allowance	0.18%	0.19%
Interest income for loans classified as nonperforming	$ 66	$ 43
Credit Card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	2,240	1,192
Nonperforming Loans	9	10
Nonperforming Loans Without an Allowance	0	0
Credit Card \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	2,135	1,110
Nonperforming Loans Without an Allowance	0	0
Credit Card \| International card businesses:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	105	82
Nonperforming Loans	9	10
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	634	391
Nonperforming Loans Without an Allowance	8	4
Consumer Banking \| Auto
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	595	344
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	39	47
Nonperforming Loans Without an Allowance	8	4
Commercial Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	3
Nonperforming Loans	701	699
Nonperforming Loans Without an Allowance	540	525
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	3
Nonperforming Loans	271	383
Nonperforming Loans Without an Allowance	246	268
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	430	316
Nonperforming Loans Without an Allowance	$ 294	$ 257

Financing Receivable, Nonaccrual, No Allowance, Percent Past Due

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- Definition

Financing Receivable, Percent 90 Days Past Due and Still Accruing

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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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- 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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Amortized cost of financing receivable on nonaccrual status. Excludes net investment in lease.

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