Earnings per Share - Calculation of Earnings (Loss) per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended				6 Months Ended
		Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Line Items]
Net loss		$ (35,023)	$ (19,328)	$ (41,336)	$ (367,199)	$ (54,351)	$ (408,535)
Less: Net (income) loss allocated to participating restricted stockholders		0		0		0	0
Basic and diluted earnings available to common stockholders		$ (35,023)		$ (41,336)		$ (54,351)	$ (408,535)
Common shares/units:
Common shares outstanding — basic		37,983		37,595		37,907	37,582
Dilutive effect of potential common shares		0		0		0	0
Common shares outstanding — diluted		37,983		37,595		37,907	37,582
Net earnings (loss) per share:
Basic		$ (0.92)		$ (1.10)		$ (1.43)	$ (10.87)
Diluted		$ (0.92)		$ (1.10)		$ (1.43)	$ (10.87)
Warrants [Member]
Net earnings (loss) per share:
Antidilutive stock options or warrants	[1]	2,174		2,174		2,174	2,174

[1] Amount represents warrants to purchase common stock that are excluded from the diluted net earnings per share calculations because of their antidilutive effect.