Loans and Card Member Receivables (Details 1) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019
Accounts receivable segment information
Card Member receivables	$ 44,728	$ 57,413
Less: Reserve for credit losses	459	619	$ 608
Card Member receivables, net	44,269	56,794
Variable Interest Entity, Primary Beneficiary [Member]
Accounts receivable segment information
Card Member receivables	3,815	8,284
Global Consumer Services Group [Member]
Accounts receivable segment information
Card Member receivables	15,816	22,844
Global Commercial Services [Member]
Accounts receivable segment information
Card Member receivables	$ 28,912	$ 34,569