Summary of Significant Accounting Policies - Restricted Cash and Cash Equivalents (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Cash, Cash Equivalents, Restricted Cash And Restricted Cash Equivalents [Roll Forward]
Purchases of invested margin deposits	$ (5,050)	$ (3,371)	$ (1,890)
Proceeds from sale of invested margin deposits	3,661	2,840	744
Net cash used in investing activities	(786)	(10,361)	(1,740)
Change in cash and cash equivalent margin deposits and guaranty funds (within financing activities)		19,256	1,329
Net cash provided by (used in) financing activities	62,026	26,000	(424)
Net (decrease) increase in cash, cash equivalents, restricted cash and cash equivalents, and cash and cash equivalent margin deposits and guaranty funds	64,357	18,528	499
Cash, cash equivalents, restricted cash and cash equivalents and cash and cash equivalent margin deposits and guaranty funds at beginning of year	83,619	65,091	64,592
Cash, cash equivalents, restricted cash and cash equivalents and cash and cash equivalent margin deposits and guaranty funds at end of year	147,976	83,619	65,091
Cash and cash equivalents	607	583	841	$ 724
Short-term restricted cash and cash equivalents	1,035	1,000	943	818
Long-term restricted cash and cash equivalents	398	408	404	330
Cash and cash equivalent margin deposits and guaranty funds	145,936	81,628	62,903	62,720
Total	147,976	83,619	65,091	64,592
As Previously Presented
Cash, Cash Equivalents, Restricted Cash And Restricted Cash Equivalents [Roll Forward]
Purchases of invested margin deposits		0	0
Proceeds from sale of invested margin deposits		0	0
Net cash used in investing activities		(9,830)	(594)
Change in cash and cash equivalent margin deposits and guaranty funds (within financing activities)		0	0
Net cash provided by (used in) financing activities		6,744	(1,753)
Net (decrease) increase in cash, cash equivalents, restricted cash and cash equivalents, and cash and cash equivalent margin deposits and guaranty funds		(197)	316
Cash, cash equivalents, restricted cash and cash equivalents and cash and cash equivalent margin deposits and guaranty funds at beginning of year	1,991	2,188	1,872
Cash, cash equivalents, restricted cash and cash equivalents and cash and cash equivalent margin deposits and guaranty funds at end of year		1,991	2,188
Total		1,991	2,188	1,872
Adjustment
Cash, Cash Equivalents, Restricted Cash And Restricted Cash Equivalents [Roll Forward]
Purchases of invested margin deposits		(3,371)	(1,890)
Proceeds from sale of invested margin deposits		2,840	744
Net cash used in investing activities		(531)	(1,146)
Change in cash and cash equivalent margin deposits and guaranty funds (within financing activities)		19,256	1,329
Net cash provided by (used in) financing activities		19,256	1,329
Net (decrease) increase in cash, cash equivalents, restricted cash and cash equivalents, and cash and cash equivalent margin deposits and guaranty funds		18,725	183
Cash, cash equivalents, restricted cash and cash equivalents and cash and cash equivalent margin deposits and guaranty funds at beginning of year	$ 81,628	62,903	62,720
Cash, cash equivalents, restricted cash and cash equivalents and cash and cash equivalent margin deposits and guaranty funds at end of year		81,628	62,903
Total		$ 81,628	$ 62,903	$ 62,720