Loans - TDR - Subsequent Defaults (Details) $ in Millions	3 Months Ended
Mar. 31, 2022 USD ($) contract	Mar. 31, 2021 USD ($) contract
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	24,491	24,372
Total Loans \| $	$ 94	$ 67
Credit Card
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	22,519	22,336
Total Loans \| $	$ 30	$ 38
Consumer Banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1,971	2,036
Total Loans \| $	$ 33	$ 29
Consumer Banking \| Auto
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1,971	2,031
Total Loans \| $	$ 33	$ 29
Consumer Banking \| Retail banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	0	5
Total Loans \| $	$ 0	$ 0
Commercial Banking
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	0
Total Loans \| $	$ 31	$ 0
Commercial Banking \| Commercial And Industrial [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	1	0
Total Loans \| $	$ 31	$ 0
Domestic credit card: \| Credit Card
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	6,012	5,134
Total Loans \| $	$ 11	$ 10
International card businesses: \| Credit Card
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Contracts \| contract	16,507	17,202
Total Loans \| $	$ 19	$ 28

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- Definition

Number of financing receivable contracts modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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Amount of financing receivable modified as troubled debt restructuring within previous 12 months, with subsequent payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953682-111524

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