Loans and Accounts Receivable (Details 7) number in Thousands, $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts (in thousands)	4	3	7	6
Aggregated Outstanding Balance Upon Payment Default	$ 23	$ 12	$ 44	$ 23
Card Member Loans [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts (in thousands)	3	2	5	4
Aggregated Outstanding Balance Upon Payment Default	$ 18	$ 9	$ 36	$ 18
Card Member Receivables [Member]
Financing Receivable, Troubled Debt Restructuring [Line Items]
Number of Accounts (in thousands)	1	1	2	2
Aggregated Outstanding Balance Upon Payment Default	$ 5	$ 3	$ 8	$ 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=118936363&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=118936363&loc=SL6953682-111524

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