Earnings Per Share (Detail) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Numerator:
Net loss attributable to stockholders		$ (190)	$ (688)
Net loss attributable to stockholders, net of earnings allocated to participating securities		$ (190)	$ (688)
Denominator:
Weighted average shares outstanding – basic		235	238
Unvested restricted shares		1
Weighted average shares outstanding – diluted		236	238
Loss per share - Basic	[1]	$ (0.81)	$ (2.89)
Loss per share - Diluted	[1]	$ (0.81)	$ (2.89)

[1] Per share amounts are calculated based on unrounded numbers.