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					6 Months Ended		9 Months Ended	12 Months Ended
	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Jun. 30, 2017	Jun. 30, 2016	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net income (loss)	$ (21,529)	$ 7,407	$ 4,455	$ 2,119	$ (1,358)	$ (14,122)	$ 760	$ 5,215	$ 7,299	$ (6,788)	$ 8,217
Weighted average shares outstanding	27,468			27,024		27,358	26,923
Effect of dilutive stock options				163			127
Diluted shares outstanding	27,468			27,187		27,358	27,050
Basic net income (loss) per share	$ (0.78)		$ 0.16	$ 0.08	$ (0.05)	$ (0.52)	$ 0.03	$ 0.19	$ 0.27	$ (0.32)
Diluted net income (loss) per share	$ (0.78)		$ 0.16	$ 0.08	$ (0.05)	$ (0.52)	$ 0.03	$ 0.19	$ 0.27	$ (0.32)