Derivative Instruments - Credit Derivatives (Details) - USD ($) $ in Millions	Jun. 30, 2019	Dec. 31, 2018
Total credit derivatives and credit-related notes
Protection sold	$ (629,112)	$ (738,464)
Protection purchased with identical underlyings	651,619	749,766
Net protection (sold)/purchased	22,507	11,302
Other protection purchased	22,246	20,966
Total credit derivatives
Total credit derivatives and credit-related notes
Protection sold	(629,112)	(738,464)
Protection purchased with identical underlyings	651,619	749,766
Net protection (sold)/purchased	22,507	11,302
Other protection purchased	13,434	12,541
Credit default swaps
Total credit derivatives and credit-related notes
Protection sold	(579,081)	(697,220)
Protection purchased with identical underlyings	590,894	707,282
Net protection (sold)/purchased	11,813	10,062
Other protection purchased	4,323	4,053
Other credit derivatives
Total credit derivatives and credit-related notes
Protection sold	(50,031)	(41,244)
Protection purchased with identical underlyings	60,725	42,484
Net protection (sold)/purchased	10,694	1,240
Other protection purchased	9,111	8,488
Credit-related notes
Total credit derivatives and credit-related notes
Protection sold	0	0
Protection purchased with identical underlyings	0	0
Net protection (sold)/purchased	0	0
Other protection purchased	$ 8,812	$ 8,425