Income Taxes - EGTS - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Current:
Federal	$ (1,463)	$ (1,701)	$ (1,537)
State	(65)	(177)	(121)
Total current	(1,449)	(1,778)	(1,572)
Deferred:
Federal	(408)	1,037	1,438
State	(49)	(476)	424
Total deferred	(462)	650	1,883
Total	(1,916)	(1,132)	308
EGTS
Current:
Federal	5	(22)	48
State	12	(10)	6
Total current	17	(32)	54
Deferred:
Federal	64	67	(93)
State	28	26	(28)
Total deferred	92	93	(121)
Total	$ 109	$ 61	$ (67)