Loss Per Share - Computation of Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Earnings Per Share [Abstract]
Loss available to common stockholders	$ (194)	$ (1,377)
Weighted-average shares outstanding, basic (in shares)	327.4	325.0
Weighted-average shares outstanding, diluted(in shares)	327.4	325.0
Loss per share, basic (in dollars per share)	$ (0.59)	$ (4.24)
Loss per share, diluted (in dollars per share)	$ (0.59)	$ (4.24)
CARES Act Loan Warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Warrants to purchase securities (in shares)	10.0
CARES Act Loan Warrants | Minimum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Warrant exercise price (in dollars per share)	$ 31.50
CARES Act Loan Warrants | Maximum
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Warrant exercise price (in dollars per share)	$ 53.92
Stock warrants
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	1.5	1.5
Employee stock awards
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Potentially dilutive securities (in shares)	0.7	0.7