Derivative Instruments - Credit Derivatives, Protection Sold, Notional and Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Protection sold credit derivatives and credit related notes ratings/maturity profile
Protection sold credit derivatives and credit related notes ratings/maturity profile - less than 1 year	$ (381,643)	$ (416,406)
Protection sold credit derivatives and credit-related notes ratings/maturity profile - from 1-5 years	(553,632)	(944,378)
Protection sold credit derivatives and credit-related notes ratings/maturity profile - more than 5 years	(62,598)	(68,055)
Total notional amount	(997,873)	(1,428,839)
Fair value of receivables	16,025	24,362
Fair value of payables	(11,625)	(25,727)
Net fair value	4,400	(1,365)
Investment-grade
Protection sold credit derivatives and credit related notes ratings/maturity profile
Protection sold credit derivatives and credit related notes ratings/maturity profile - less than 1 year	(273,688)	(307,211)
Protection sold credit derivatives and credit-related notes ratings/maturity profile - from 1-5 years	(383,586)	(699,227)
Protection sold credit derivatives and credit-related notes ratings/maturity profile - more than 5 years	(39,281)	(46,970)
Total notional amount	(696,555)	(1,053,408)
Fair value of receivables	7,841	13,539
Fair value of payables	(3,055)	(6,836)
Net fair value	4,786	6,703
Noninvestment-grade
Protection sold credit derivatives and credit related notes ratings/maturity profile
Protection sold credit derivatives and credit related notes ratings/maturity profile - less than 1 year	(107,955)	(109,195)
Protection sold credit derivatives and credit-related notes ratings/maturity profile - from 1-5 years	(170,046)	(245,151)
Protection sold credit derivatives and credit-related notes ratings/maturity profile - more than 5 years	(23,317)	(21,085)
Total notional amount	(301,318)	(375,431)
Fair value of receivables	8,184	10,823
Fair value of payables	(8,570)	(18,891)
Net fair value	$ (386)	$ (8,068)