Earnings Per Share And Stockholders' Equity (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Basic earnings (loss) per common share
Net income (loss) from continuing operations	$ (6,716)	$ 635	$ (8,729)	$ 1,266
Loss from discontinued operations, net of tax	(1,415)	0	(1,415)	0
NET INCOME (LOSS)	(8,131)	635	(10,144)	1,266
Less: Preferred stock dividends	(222)	0	(441)	0
NET INCOME (LOSS) ATTRIBUTABLE TO COMMON STOCKHOLDERS	(8,353)	635	(10,585)	1,266
Less: Net income allocated to participating securities	0	(3)	0	(6)
Net income (loss) attributable to common stock, net of participating securities	$ (8,353)	$ 632	$ (10,585)	$ 1,260
Weighted average number of basic shares (in shares)	915.5	748.3	906.2	748.7
Basic earnings (loss) per common share (in usd per share)	$ (9.12)	$ 0.84	$ (11.68)	$ 1.68
Weighted average number of basic shares (in shares)	915.5	748.3	906.2	748.7
Net income (loss) attributable to common stock, net of participating securities	$ (8,353)	$ 632	$ (10,585)	$ 1,260
Dilutive securities (in shares)	0.0	1.2	0.0	1.3
Total diluted weighted average common shares (in shares)	915.5	749.5	906.2	750.0
Net income (loss) attributable to common stockholders per share—diluted (in usd per share)	$ (9.12)	$ 0.84	$ (11.68)	$ 1.68
Berkshire Warrants, Common Stock Warrants, and options excluded from diluted shares (in shares)	200.0		200.0