Earnings Per Share And Stockholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Basic earnings (loss) per common share
Net income (loss) from continuing operations	$ (3,655)	$ (737)	$ (12,384)	$ 529
Income (loss) from discontinued operations, net of tax	80	(15)	(1,335)	(15)
NET INCOME (LOSS)	(3,575)	(752)	(13,719)	514
Less: Net income attributable to noncontrolling interest	0	(42)	0	(42)
Less: Preferred stock dividends	(203)	(118)	(644)	(118)
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCKHOLDERS	(3,778)	(912)	(14,363)	354
Less: Net income allocated to participating securities	0	0	0	(1)
Net income (loss) attributable to common stock, net of participating securities	$ (3,778)	$ (912)	$ (14,363)	$ 353
Weighted average number of basic shares (in shares)	929.3	845.7	913.9	781.1
Basic earnings (loss) per common share (in usd per share)	$ (4.07)	$ (1.08)	$ (15.72)	$ 0.45
Weighted average number of basic shares (in shares)	929.3	845.7	913.9	781.1
Net income (loss) attributable to common stock, net of participating securities	$ (3,778)	$ (912)	$ (14,363)	$ 353
Dilutive securities (in shares)	0.0	0.0	0.0	1.1
Total diluted weighted average common shares (in shares)	929.3	845.7	913.9	782.2
Net income (loss) attributable to common stockholders per share—diluted (in usd per share)	$ (4.07)	$ (1.08)	$ (15.72)	$ 0.45
Berkshire Warrants, Common Stock Warrants, and options excluded from diluted shares (in shares)	200.0		200.0