Significant Credit Concentrations (Details 1) - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Card Member loans and receivables exposure
On-balance sheet	$ 177	$ 185
Card Member Loans and Receivables [Member]
Card Member loans and receivables exposure
On-balance sheet	117	145
Unused lines-of-credit	314	306
U.S. [Member] | Card Member Loans and Receivables [Member]
Card Member loans and receivables exposure
On-balance sheet	95	115
Unused lines-of-credit	251	245
Non-U.S. [Member] | Card Member Loans and Receivables [Member]
Card Member loans and receivables exposure
On-balance sheet	22	30
Unused lines-of-credit	$ 63	$ 61