Consolidated Statements of Changes in Equity (Unaudited) - USD ($) $ in Millions	Total	Preferred Stock	Common Stock	Additional Paid-in Capital	Long-term Income Tax Receivable	Retained Earnings	Accumulated Other Comprehensive (Loss) Income, Net	Noncontrolling Interest
Balance at Dec. 31, 2019	$ 32,578	$ 0	$ 0	$ 6,389	$ (530)	$ 28,296	$ (1,706)	$ 129
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	4,638					4,628		10
Other comprehensive income (loss)	(177)						(177)
Preferred stock dividend	0
Common stock purchases	(126)			(6)		(120)
Distributions to noncontrolling interests	(11)							(11)
Purchase of noncontrolling interest	(33)			(5)				(28)
Other equity transactions	0			(1)				1
Balance at Sep. 30, 2020	36,869	0	0	6,377	(530)	32,804	(1,883)	101
Balance at Jun. 30, 2020	33,785	0	0	6,377	(530)	29,962	(2,125)	101
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	2,845					2,842		3
Other comprehensive income (loss)	242						242
Preferred stock dividend	0
Distributions to noncontrolling interests	(4)							(4)
Other equity transactions	1							1
Balance at Sep. 30, 2020	36,869	0	0	6,377	(530)	32,804	(1,883)	101
Balance at Dec. 31, 2020	46,977	3,750	0	6,377	(658)	35,093	(1,552)	3,967
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	4,518					4,207		311
Other comprehensive income (loss)	33						29	4
Preferred stock redemptions	(1,450)	(1,450)
Preferred stock dividend	(101)					(101)
Distributions to noncontrolling interests	(364)							(364)
Contributions	9							9
Purchase of noncontrolling interest	(3)			(3)
Other equity transactions	(3)							(3)
Balance at Sep. 30, 2021	49,616	2,300	0	6,374	(658)	39,199	(1,523)	3,924
Balance at Jun. 30, 2021	49,365	3,750	0	6,377	(658)	37,303	(1,360)	3,953
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	2,025					1,922		103
Other comprehensive income (loss)	(163)						(163)
Preferred stock redemptions	(1,450)	(1,450)
Preferred stock dividend	(26)					(26)
Distributions to noncontrolling interests	(130)							(130)
Purchase of noncontrolling interest	(3)			(3)
Other equity transactions	(2)							(2)
Balance at Sep. 30, 2021	$ 49,616	$ 2,300	$ 0	$ 6,374	$ (658)	$ 39,199	$ (1,523)	$ 3,924