Net Income (Loss) Per Common Share - Summary of Net Income (Loss) Per Common Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Earnings Per Share [Line Items]
Net income (loss)									$ 123,385	$ 26,762	$ (14,746)
Basic weighted-average common shares outstanding (in shares)									37,276	32,044	24,440
Effect of dilutive stock options (in shares)									288	612	0
Effect of dilutive restricted stock (in shares)									1,296	0	0
Effect of dilutive performance restricted stock (in shares)									32	0	0
Diluted weighted-average common shares outstanding (in shares)									38,892	32,656	24,440
Basic income (loss) per common share outstanding (in dollars per share)	$ 2.58	$ 0.23	$ 0.37	$ 0.11	$ 0.13	$ 0.14	$ 0.24	$ 0.34	$ 3.31	$ 0.84	$ (0.60)
Diluted income (loss) per common share outstanding (in dollars per share)	$ 2.47	$ 0.22	$ 0.35	$ 0.11	$ 0.13	$ 0.13	$ 0.24	$ 0.34	$ 3.17	$ 0.82	$ (0.60)
Stock Options | Nonvested Restricted Stock
Earnings Per Share [Line Items]
Antidilutive securities excluded from diluted income (loss) per common share (in shares)									604	1,563	2,269