Significant Credit Concentrations (Details 1) - USD ($) $ in Billions	Dec. 31, 2015	Dec. 31, 2014
Card Member loans and receivables exposure
On-balance sheet	$ 118	$ 115
Individuals [Member]
Card Member loans and receivables exposure
Unused lines-of-credit	297	278
U.S. [Member]
Card Member loans and receivables exposure
On-balance sheet	99	94
U.S. [Member] | Individuals [Member]
Card Member loans and receivables exposure
Unused lines-of-credit	259	234
Non-U.S. [Member]
Card Member loans and receivables exposure
On-balance sheet	19	21
Non-U.S. [Member] | Individuals [Member]
Card Member loans and receivables exposure
Unused lines-of-credit	$ 38	$ 44