Loans - 90+ Day Delinquent Loans Accruing Interest and Nonperforming Loans (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 2,023	$ 2,233
Nonperforming Loans	$ 929	$ 813
Percentage, 90 Days Past Due and Accruing	0.80%	0.90%
Percentage, Nonperforming Loans	0.40%	0.30%
Credit Card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 1,992	$ 2,233
Nonperforming Loans	23	22
Credit Card \| Domestic credit card
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	1,873	2,111
Credit Card \| International card business
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	119	122
Nonperforming Loans	23	22
Consumer Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	$ 457	$ 479
Percentage, Nonperforming Loans	0.74%	0.81%
Consumer Banking \| Auto
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 0	$ 0
Nonperforming Loans	$ 432	$ 449
Percentage, Nonperforming Loans	0.73%	0.80%
Consumer Banking \| Retail banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 0	$ 0
Nonperforming Loans	$ 25	$ 30
Percentage, Nonperforming Loans	0.91%	1.04%
Commercial Banking
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	$ 31	$ 0
Nonperforming Loans	449	312
Commercial Banking \| Total commercial lending
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	31	0
Nonperforming Loans	449	306
Commercial Banking \| Commercial and multifamily real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	31	0
Nonperforming Loans	36	83
Commercial Banking \| Commercial and industrial
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	413	223
Commercial Banking \| Small-ticket commercial real estate
Financing Receivable, Past Due [Line Items]
90 Days Past Due and Accruing	0	0
Nonperforming Loans	$ 0	$ 6

Financing Receivable, Percent 90 Days Past Due and Still Accruing

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

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- Definition

Amount of financing receivable on nonaccrual status.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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