Loans and Card Member Receivables (Details 5) account in Thousands, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2021 USD ($) account	Jun. 30, 2020 USD ($) account	Jun. 30, 2021 USD ($) account	Jun. 30, 2020 USD ($) account
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	13	5	22	10
Aggregated Outstanding Balance Upon Default \| $	$ 91	$ 34	$ 162	$ 71
Card Member Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	9	3	16	7
Aggregated Outstanding Balance Upon Default \| $	$ 69	$ 24	$ 116	$ 52
Card Member Receivables
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	3	1	4	2
Aggregated Outstanding Balance Upon Default \| $	$ 19	$ 9	$ 38	$ 18
Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1	1	2	1
Aggregated Outstanding Balance Upon Default \| $	$ 3	$ 1	$ 8	$ 1

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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