Card Member Receivables and Loans (Details 2) - USD ($) $ in Millions	Dec. 31, 2017	Dec. 31, 2016
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	$ 20,276	$ 18,218
U.S. Consumer Services [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	3,557	3,518
U.S. Consumer Services [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	3,531	3,501
U.S. Consumer Services [Member] \| Card Member Receivables [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	10	9
U.S. Consumer Services [Member] \| Card Member Receivables [Member] \| 60 To 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	6	3
U.S. Consumer Services [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	10	5
International Consumer and Network Services [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	1,827	1,526
Card Member loans total aging	561	476
International Consumer and Network Services [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	1,805	1,506
International Consumer and Network Services [Member] \| Card Member Receivables [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	8	6
International Consumer and Network Services [Member] \| Card Member Receivables [Member] \| 60 To 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	5	4
International Consumer and Network Services [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	9	10
International Consumer and Network Services [Member] \| Card Member Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	557	472
International Consumer and Network Services [Member] \| Card Member Loans [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	1	1
International Consumer and Network Services [Member] \| Card Member Loans [Member] \| 60 To 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	1	1
International Consumer and Network Services [Member] \| Card Member Loans [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	2	2
Global Commercial Services [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	14,892	13,174
Global Corporate Payments [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	13,480	11,956
Global Corporate Payments [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	112	108
Global Small Business Services [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	1,412	1,218
Global Small Business Services [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	1,397	1,202
Global Small Business Services [Member] \| Card Member Receivables [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	5	9
Global Small Business Services [Member] \| Card Member Receivables [Member] \| 60 To 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	4	2
Global Small Business Services [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	$ 6	$ 5

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 7A
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953401-111524

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

+ References

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- Definition

Amount before allowance of credit card loans issued to individuals. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.7(a)(4),(b))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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- Definition

Amount representing an agreement for an unconditional promise by the maker to pay the entity (holder) a definite sum of money at a future date. Such amount may include accrued interest receivable in accordance with the terms of the note. The note also may contain provisions and related items including a discount or premium, payable on demand, secured, or unsecured, interest bearing or noninterest bearing, among a myriad of other features and characteristics. Excludes amounts related to receivables held-for-sale.

+ References

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