Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 1,195	$ 1,302
Nonperforming Loans	1,100	995
Nonperforming Loans Without an Allowance	$ 529	$ 449
Percentage, 90 Days Past Due and Accruing	0.43%	0.52%
Percentage, Nonperforming Loans	0.40%	0.40%
Percentage, Nonperforming Loans Without an Allowance	0.19%	0.18%
Interest income for loans classified as nonperforming	$ 43	$ 39
Credit Card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,192	1,251
Nonperforming Loans	10	21
Nonperforming Loans Without an Allowance	0	0
Credit Card \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,110	1,169
Nonperforming Loans Without an Allowance	0	0
Credit Card \| International card businesses:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	82	82
Nonperforming Loans	10	21
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	391	324
Nonperforming Loans Without an Allowance	4	0
Consumer Banking \| Auto
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	344	294
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	47	30
Nonperforming Loans Without an Allowance	4	0
Commercial Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	3	51
Nonperforming Loans	699	650
Nonperforming Loans Without an Allowance	525	449
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	3	51
Nonperforming Loans	383	200
Nonperforming Loans Without an Allowance	268	184
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	316	450
Nonperforming Loans Without an Allowance	$ 257	$ 265

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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Amount of financing receivable on nonaccrual status with no allowance for credit loss.

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

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- Definition

Amount of financing receivable 90 days or more past due and still accruing.

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Amount of financing receivable on nonaccrual status.

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