Earnings Per Share (Schedule of Earnings Per Share) (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Net income (loss)	$ (2,675)	$ 80
Number of common shares:
Weighted average outstanding (in shares)	1,114,610,964	675,385,145
Weighted average and potential dilutive outstanding (in shares)	1,114,610,964	679,867,825
Earnings (loss) per common share
Basic (in dollars per share)	$ (2.40)	$ 0.12
Diluted (in dollars per share)	$ (2.40)	$ 0.12
Stock options
Number of common shares:
Issued upon assumed exercise of outstanding stock options (in shares)	0	0
Restricted Common Stock
Number of common shares:
Effect of issuance of non-vested restricted common stock (in shares)	0	870,541
Restricted stock units
Number of common shares:
Effect of issuance of non-vested restricted common stock (in shares)	0	804,944
Performance units
Number of common shares:
Effect of issuance of non-vested performance units (in shares)	0	2,807,195