Derivative Instruments - Credit Derivatives, Protection Sold, Notional and Fair Value (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Protection sold credit derivatives and credit related notes ratings/maturity profile
Less than 1 year	$ (125,714)	$ (161,587)
From 1-5 years	(404,985)	(399,176)
More than 5 years	(44,479)	(51,970)
Total notional amount	(575,178)	(612,733)
Fair value of receivables	9,474	10,455
Fair value of payables	(3,377)	(3,718)
Net fair value	6,097	6,737
Investment-grade
Protection sold credit derivatives and credit related notes ratings/maturity profile
Less than 1 year	(93,905)	(119,788)
From 1-5 years	(307,648)	(311,407)
More than 5 years	(35,326)	(42,129)
Total notional amount	(436,879)	(473,324)
Fair value of receivables	5,521	6,168
Fair value of payables	(835)	(901)
Net fair value	4,686	5,267
Noninvestment-grade
Protection sold credit derivatives and credit related notes ratings/maturity profile
Less than 1 year	(31,809)	(41,799)
From 1-5 years	(97,337)	(87,769)
More than 5 years	(9,153)	(9,841)
Total notional amount	(138,299)	(139,409)
Fair value of receivables	3,953	4,287
Fair value of payables	(2,542)	(2,817)
Net fair value	$ 1,411	$ 1,470