(Loss) Earnings per Share - Schedule of Earnings per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share [Abstract]
Basic (loss) earnings per share	$ (79,237)	$ 98,028	$ (266,785)	$ 113,659
Diluted (loss) earnings per share	$ (79,237)	$ 98,028	$ (266,785)	$ 113,659
Basic (loss) earnings per share	78,154	78,164	78,153	81,003
Effect of dilutive incentive-based awards, Shares		640		735
Diluted (loss) earnings per share	78,154	78,804	78,153	81,738
Basic (loss) per share, Per Share Amount	$ (1.01)	$ 1.25	$ (3.41)	$ 1.40
Diluted (loss) per share, Per Share Amount	$ (1.01)	$ 1.24	$ (3.41)	$ 1.39