Earnings (Loss) Per Common Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Jun. 30, 2020
Basic EPS:
Net income (loss)	$ 127	$ (1,993)	$ (8,885)
Weighted average common shares outstanding (in shares)	650,345	644,015	483,888
Basic EPS (in dollars per share)	$ 0.20	$ (3.09)	$ (18.36)
Diluted EPS:
Net income (loss) for purposes of computing diluted EPS	$ 127	$ (1,993)	$ (8,885)
Share computation for diluted EPS:
Basic weighted average common shares outstanding (in shares)	650,345	644,015	483,888
Dilutive effect of stock awards (in shares)	1,579	0	0
Dilutive effect of warrants (in shares)	3,198	0	0
Diluted weighted average common shares outstanding (in shares)	655,122	644,015	483,888
Diluted EPS (in dollars per share)	$ 0.19	$ (3.09)	$ (18.36)
Convertible Senior Notes 6.50% Due 2025 | Senior Notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Fixed interest rate per annum	6.50%			6.50%
6.50% convertible senior notes
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	61,728	61,728	31,882
Restricted stock unit awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Antidilutive securities (in shares)	3,987	3,420	4,584