Loans and Accounts Receivable (Details 6) $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($) M	Mar. 31, 2017 USD ($) M
Troubled Debt Restructurings
Financing Receivable, Modifications [Line Items]
Number of Accounts	12,000	10,000
Aggregated Outstanding Balance	$ 110	$ 85
Card Member Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts	11,000	8,000
Aggregated Outstanding Balance	$ 81	$ 57
Average basis point reduction in interest rate by class of Card Member loans	13.00%	13.00%
Card Member Receivables [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts	1,000	2,000
Aggregated Outstanding Balance	$ 29	$ 28
Average payment term extension \| M	28	22

The average basis point reduction in interest rate by class of cardmember loan.

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- Definition

The average period for payment term extension for cardmember 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/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

+ Details

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- Definition

Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Details

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