Net Income (Loss) Per Share - Summary of Net Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Earnings Per Share [Abstract]
Income (loss) from continuing operations	$ (220,189)	$ (13,784)	$ (24,511)	$ (5,983)	$ 53,325	$ (3,480)	$ (26,374)	$ 1,893	$ (264,467)	$ 25,364	$ (9,490)
Income from discontinued operations, net of tax					$ (2,507)	$ 129,441	$ 5,236	$ 5,518	0	137,688	16,153
Net income (loss)									$ (264,467)	$ 163,052	$ 6,663
Weighted average shares outstanding (in shares)									31,678	27,433	27,016
Effect of dilutive stock options (in shares)									0	322	0
Weighted average shares outstanding (in shares)									31,678	27,755	27,016
Basic income (loss) from continuing operations per share (in usd per share)	$ (5.25)	$ (0.48)	$ (0.89)	$ (0.22)	$ 1.93	$ (0.13)	$ (0.96)	$ 0.07	$ (8.35)	$ 0.92	$ (0.35)
Basic income from discontinued operations per share (in shares)									0.00	5.02	0.60
Basic net income (loss) per share (in usd per share)	(5.25)	(0.48)	(0.89)	(0.22)	1.84	4.57	(0.77)	0.27	(8.35)	5.94	0.25
Diluted income (loss) from continuing operations per share (in usd per share)	(5.25)	(0.48)	(0.89)	(0.22)	1.91	(0.13)	(0.96)	0.07	(8.35)	0.91	(0.35)
Diluted income from discontinued operations per share (in usd per share)									0.00	4.96	0.60
Diluted net income (loss) per share (in usd per share)	$ (5.25)	$ (0.48)	$ (0.89)	$ (0.22)	$ 1.82	$ 4.57	$ (0.77)	$ 0.27	(8.35)	5.87	0.25
Cash dividends per common share (in usd per share)									$ 0.28	$ 0.28	$ 0.28