Loans and Accounts Receivable (Details 7) pure in Thousands, $ in Millions	3 Months Ended
Mar. 31, 2018 USD ($)	Mar. 31, 2017 USD ($)
Troubled Debt Restructurings That Subsequently Defaulted [Domain]
Financing Receivable, Modifications [Line Items]
Number of Accounts	3	3
Aggregated Outstanding Balance Upon Payment Default	$ 11	$ 12
Card Member Loans [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts	2	2
Aggregated Outstanding Balance Upon Payment Default	$ 9	$ 11
Card Member Receivables [Member]
Financing Receivable, Modifications [Line Items]
Number of Accounts	1	1
Aggregated Outstanding Balance Upon Payment Default	$ 2	$ 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 receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 34
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

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