Loans and Card Member Receivables (Details 5) account in Thousands, $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($) account	Dec. 31, 2019 USD ($) account	Dec. 31, 2018 USD ($) account
Financing Receivable, Modifications [Line Items]
Number of Accounts \| account	328	87	57
Outstanding Balance \| $	$ 3,894	$ 812	$ 487
Card Member Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts \| account	272	78	51
Outstanding Balance \| $	$ 2,347	$ 602	$ 377
Average Interest Rate Reduction	14.00%	13.00%	12.00%
Card Member Receivables [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts \| account	47	9	6
Outstanding Balance \| $	$ 1,202	$ 210	$ 110
Average Payment Term Extension	19 months	26 months	28 months
Other Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts \| account	9
Outstanding Balance \| $	$ 345
Average Interest Rate Reduction	3.00%
Average Payment Term Extension	16 months

Average Interest Rate Reduction By Class Of Financial Instrument

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- Definition

The average period for payment term extension for Card Member receivables modified in a TDR.

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=121611835&loc=SL6953676-111524

+ Details

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- Definition

Amount, after troubled debt restructuring, of modified financing receivable.

+ References

+ Details

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- Details

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- Details

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- Details

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