Derivative Instruments - Credit Derivatives, Protection Sold, Notional and Fair Value (Details) - USD ($) $ in Millions	Sep. 30, 2021	Dec. 31, 2020
Protection sold credit derivatives ratings/maturity profile
Protection sold credit derivatives ratings/maturity profile - less than 1 year	$ (147,740)	$ (125,338)
Protection sold credit derivatives ratings/maturity profile - from 1-5 years	(387,760)	(404,167)
Protection sold credit derivatives ratings/maturity profile - more than 5 years	(102,894)	(44,479)
Total notional amount	(638,394)	(573,984)
Fair value of receivables	7,106	9,325
Fair value of payables	(2,483)	(3,376)
Net fair value	4,623	5,949
Investment-grade
Protection sold credit derivatives ratings/maturity profile
Protection sold credit derivatives ratings/maturity profile - less than 1 year	(116,560)	(93,529)
Protection sold credit derivatives ratings/maturity profile - from 1-5 years	(291,195)	(306,830)
Protection sold credit derivatives ratings/maturity profile - more than 5 years	(78,593)	(35,326)
Total notional amount	(486,348)	(435,685)
Fair value of receivables	3,996	5,372
Fair value of payables	(597)	(834)
Net fair value	3,399	4,538
Noninvestment-grade
Protection sold credit derivatives ratings/maturity profile
Protection sold credit derivatives ratings/maturity profile - less than 1 year	(31,180)	(31,809)
Protection sold credit derivatives ratings/maturity profile - from 1-5 years	(96,565)	(97,337)
Protection sold credit derivatives ratings/maturity profile - more than 5 years	(24,301)	(9,153)
Total notional amount	(152,046)	(138,299)
Fair value of receivables	3,110	3,953
Fair value of payables	(1,886)	(2,542)
Net fair value	$ 1,224	$ 1,411