Offsetting Arrangements - Liabilities With Offsetting Arrangements (Details) - USD ($) $ in Millions	Jun. 30, 2016	Dec. 31, 2015
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	$ 20,993	$ 11,153
Gross amounts offset in statement of condition	(13,290)	(7,021)
Net Amounts of Liabilities Presented in Statement of Condition	7,703	4,132
Derivative collateral, cash offset	(2,661)	(1,118)
Gross amounts of recognized liabilities	47,234	46,766
Gross amounts offset in statement of condition	(38,251)	(38,997)
Net Amounts of Liabilities Presented in Statement of Condition	8,983	7,769
Gross amounts of recognized liabilities	68,227	57,919
Gross amounts offset in statement of condition	(51,541)	(46,018)
Total, net amount of liabilities presented in statement of condition	16,686	11,901
Securities sold under repurchase agreements	4,350	4,499
Securities lending, fair value, amount not offset against collateral	4,633	3,270
Foreign exchange contracts
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	20,620	10,868
Gross amounts offset in statement of condition	(10,615)	(5,896)
Net Amounts of Liabilities Presented in Statement of Condition	10,005	4,972
Interest-rate contracts
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	212	182
Gross amounts offset in statement of condition	(9)	(5)
Net Amounts of Liabilities Presented in Statement of Condition	203	177
Other derivative contracts
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	161	103
Gross amounts offset in statement of condition	(5)	(2)
Net Amounts of Liabilities Presented in Statement of Condition	$ 156	$ 101