Card Member Receivables and Card Member Loans 2 (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables total aging	$ 25,557	$ 24,596
Global Consumer Services Group [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	9,766	8,432
Card Member receivables total aging	9,847	8,485
Global Consumer Services Group [Member] \| Card Member Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	689	636
Card Member loans total aging	697	641
Global Consumer Services Group [Member] \| 30-59 Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	29	17
Global Consumer Services Group [Member] \| 30-59 Days Past Due [Member] \| Card Member Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	3	2
Global Consumer Services Group [Member] \| 60-89 Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	16	12
Global Consumer Services Group [Member] \| 60-89 Days Past Due [Member] \| Card Member Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	2	1
Global Consumer Services Group [Member] \| 90+ Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	36	24
Global Consumer Services Group [Member] \| 90+ Days Past Due [Member] \| Card Member Loans [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	3	2
Global Small Business Services [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Current	1,996	1,787
Card Member receivables total aging	2,020	1,805
Global Small Business Services [Member] \| 30-59 Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	10	7
Global Small Business Services [Member] \| 60-89 Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	5	4
Global Small Business Services [Member] \| 90+ Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	9	7
Global Corporate Payments [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Card Member receivables total aging	13,690	14,306
Global Corporate Payments [Member] \| 90+ Days Past Due [Member] \| Card Member Receivables [Member]
Financing Receivable, Recorded Investment, Aging [Abstract]
Period past due	$ 105	$ 103

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Amount of financing receivable not past due.

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Amount of financing receivable past due.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount, before allowance for credit loss, of financing receivable.

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