Card Member Receivables and Card Member Loans 2 (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	$ 26,007	$ 24,596
Global Consumer Services Group [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	8,902	8,485
Card Member loans Total aging	643	641
Global Consumer Services Group [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	8,840	8,432
Global Consumer Services Group [Member] \| Card Member Receivables [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	23	17
Global Consumer Services Group [Member] \| Card Member Receivables [Member] \| 60 To 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	13	12
Global Consumer Services Group [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	26	24
Global Consumer Services Group [Member] \| Card Member Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	638	636
Global Consumer Services Group [Member] \| Card Member Loans [Member] \| 30 to 59 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	2	2
Global Consumer Services Group [Member] \| Card Member Loans [Member] \| 60 To 89 Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	1	1
Global Consumer Services Group [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	17,105	16,111
Global Small Business Services [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	2,001	1,805
Global Small Business Services [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	1,981	1,787
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	8	7
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	4
Global Small Business Services [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	8	7
Global Corporate Payments [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables Total Aging	15,104	14,306
Global Corporate Payments [Member] \| Card Member Receivables [Member] \| 90+ Days Past Due [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	$ 95	$ 103

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- Definition

Financing receivables that are current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-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://fasb.org/us-gaap/role/ref/legacyRef
-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

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-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

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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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