Net Income (Loss) Per Common Share - Calculations for Basic and Diluted Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Numerator:
Net income (loss)—basic and diluted	$ (808)	$ 703	$ (1,081)	$ 1,323
Denominator:
Basic weighted-average common shares outstanding (in shares)	159.6	161.1	160.0	161.1
Diluted weighted-average shares	159.6	162.9	160.0	162.7
Earnings (loss) per share:
Basic (in USD per share)	$ (5.06)	$ 4.36	$ (6.76)	$ 8.21
Diluted (in USD per share)	$ (5.06)	$ 4.31	$ (6.76)	$ 8.13
Number of anti-dilutive stock-based awards (in shares)	2.0	0.4	2.2	1.0
Stock Options
Denominator:
Effect of stock-based awards (in shares)	0.0	1.2	0.0	1.0
Nonvested shares
Denominator:
Effect of stock-based awards (in shares)	0.0	0.6	0.0	0.6