Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 1,302	$ 2,407
Nonperforming Loans	995	$ 983
Nonperforming Loans Without an Allowance	$ 449
Percentage, 90 Days Past Due and Accruing	0.50%	0.90%
Percentage, Nonperforming Loans	0.40%	0.40%
Percentage, Nonperforming Loans Without an Allowance	0.20%
Interest income for loans classified as nonperforming	$ 39
Credit Card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,251	$ 2,407
Nonperforming Loans	21	25
Nonperforming Loans Without an Allowance	0
Credit Card \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,169	2,277
Nonperforming Loans Without an Allowance	0
Credit Card \| International card businesses:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	82	130
Nonperforming Loans	21	25
Nonperforming Loans Without an Allowance	0
Consumer Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	324	510
Nonperforming Loans Without an Allowance	0
Consumer Banking \| Auto
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	294	487
Nonperforming Loans Without an Allowance	0
Consumer Banking \| Retail banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	30	23
Nonperforming Loans Without an Allowance	0
Commercial Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	51	0
Nonperforming Loans	650	448
Nonperforming Loans Without an Allowance	449
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	51	0
Nonperforming Loans	200	38
Nonperforming Loans Without an Allowance	184
Commercial Banking \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	450	$ 410
Nonperforming Loans Without an Allowance	$ 265

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.

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

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- Definition

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

+ References

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Amount of financing receivable on nonaccrual status.

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