Loans and Card Member Receivables (Details 5) account in Thousands, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2021 USD ($) account	Sep. 30, 2020 USD ($) account	Sep. 30, 2021 USD ($) account	Sep. 30, 2020 USD ($) account
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	6	6	28	16
Aggregated Outstanding Balance Upon Default \| $	$ 43	$ 49	$ 205	$ 120
Card Member Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	4	4	20	11
Aggregated Outstanding Balance Upon Default \| $	$ 32	$ 32	$ 148	$ 84
Card Member Receivables
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1	1	5	3
Aggregated Outstanding Balance Upon Default \| $	$ 10	$ 16	$ 48	$ 34
Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1	1	3	2
Aggregated Outstanding Balance Upon Default \| $	$ 1	$ 1	$ 9	$ 2

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.

No definition available.

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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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- Definition

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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