Commitments and Guarantees - Contractual Amounts of Credit-Related Off-Balance Sheet Financial Instruments (Details) - USD ($) $ in Millions	Dec. 31, 2015	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Indemnified securities financing	$ 320,436	$ 349,766
Stable value protection	24,583	23,409
Asset purchase agreements	3,990	4,107
Standby letters of credit	$ 4,700	$ 4,720