Loans and Card Member Receivables (Details 6) account in Thousands, $ in Millions	3 Months Ended	9 Months Ended
Sep. 30, 2020 USD ($) account	Sep. 30, 2019 USD ($) account	Sep. 30, 2020 USD ($) account	Sep. 30, 2019 USD ($) account
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	6	5	16	12
Aggregated Outstanding Balance Upon Default \| $	$ 49	$ 28	$ 120	$ 72
Card Member Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	4	4	11	9
Aggregated Outstanding Balance Upon Default \| $	$ 32	$ 23	$ 84	$ 59
Card Member Receivables [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1	1	3	3
Aggregated Outstanding Balance Upon Default \| $	$ 16	$ 5	$ 34	$ 13
Other Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1		2
Aggregated Outstanding Balance Upon Default \| $	$ 1		$ 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=121611835&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=121611835&loc=SL6953682-111524

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