Loans and Card Member Receivables (Details 5) account in Thousands, $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($) account	Mar. 31, 2020 USD ($) account
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	9	5
Aggregated Outstanding Balance Upon Default \| $	$ 71	$ 37
Card Member Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	7	4
Aggregated Outstanding Balance Upon Default \| $	$ 47	$ 28
Card Member Receivables
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1	1
Aggregated Outstanding Balance Upon Default \| $	$ 19	$ 9
Other Loans
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts \| account	1
Aggregated Outstanding Balance Upon Default \| $	$ 5

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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