Significant Credit Concentrations (Details 1) - USD ($) $ in Billions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Card Member loans and receivables exposure
On-balance sheet	$ 185	$ 177
Card Member Loans and Receivables [Member]
Card Member loans and receivables exposure
On-balance sheet	145	138
Unused lines-of-credit	306	302
U.S. [Member] | Card Member Loans and Receivables [Member]
Card Member loans and receivables exposure
On-balance sheet	115	111
Unused lines-of-credit	245	249
Non-U.S. [Member] | Card Member Loans and Receivables [Member]
Card Member loans and receivables exposure
On-balance sheet	30	27
Unused lines-of-credit	$ 61	$ 53