Commitments and Guarantees - Contractual Amounts of Credit-Related Off-Balance Sheet Financial Instruments (Details) - USD ($) $ in Millions	Sep. 30, 2016	Dec. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
Indemnified securities financing	$ 344,191	$ 320,436
Stable value protection	27,319	24,583
Asset purchase agreements	4,989	3,990
Standby letters of credit	$ 3,597	$ 4,700