Basis of Presentation (Details Textuals) $ in Millions	6 Months Ended
Jun. 30, 2019 USD ($)
Financing Receivable, Allowance for Credit Loss [Line Items]
Right-of-use asset obtained in exchange for operating lease liability	$ 700
Minimum [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses net increase, Card Member loans and receivables (as a percentage)	25.00%
Allowance for credit losses net increase, Card Member loans (as a percentage)	55.00%
Maximum [Member]
Financing Receivable, Allowance for Credit Loss [Line Items]
Allowance for credit losses net increase, Card Member loans and receivables (as a percentage)	40.00%
Allowance for credit losses net increase, Card Member loans (as a percentage)	70.00%

Accounts Receivable, Allowance for Credit Loss, Period Increase (Decrease), Percent

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- Definition

Financing Receivable, Allowance for Credit Loss, Increase (Decrease), Percent

+ 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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Period Type:	duration

- Definition

Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 55
-Paragraph 53
-URI http://asc.fasb.org/extlink&oid=77888399&loc=SL77918982-209971

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(2)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

+ Details

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Period Type:	duration

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