Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Detail) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Dec. 31, 2019
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 1,610	$ 1,610	$ 2,407
Nonperforming Loans	967	967	$ 983
Nonperforming Loans Without an Allowance	$ 324	$ 324
Percentage, 90 Days Past Due and Accruing	0.60%	0.60%	0.90%
Percentage, Nonperforming Loans	0.40%	0.40%	0.40%
Percentage, Nonperforming Loans Without an Allowance	0.10%	0.10%
Interest income for loans classified as nonperforming	$ 5	$ 11
Credit Card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,596	1,596	$ 2,407
Nonperforming Loans	23	23	25
Nonperforming Loans Without an Allowance	0	0
Credit Card \| Domestic credit card:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,502	1,502	2,277
Nonperforming Loans Without an Allowance	0	0
Credit Card \| International card businesses:
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	94	94	130
Nonperforming Loans	23	23	25
Nonperforming Loans Without an Allowance	0	0
Consumer Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0	0
Nonperforming Loans	284	284	510
Nonperforming Loans Without an Allowance	2	2
Consumer Banking \| Auto
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0	0
Nonperforming Loans	260	260	487
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	0
Nonperforming Loans	24	24	23
Nonperforming Loans Without an Allowance	2	2
Commercial Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	14	14	0
Nonperforming Loans	660	660	448
Nonperforming Loans Without an Allowance	322	322
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	14	14	0
Nonperforming Loans	167	167	38
Nonperforming Loans Without an Allowance	162	162
Commercial Banking \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0	0
Nonperforming Loans	493	493	$ 410
Nonperforming Loans Without an Allowance	$ 160	$ 160

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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