Organization and Summary of Significant Accounting Policies - Weighted Average Number of Shares Outstanding and Income Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Numerator for basic and diluted earnings per share:
Net income	$ 422	$ 3,843	$ 7,278	$ 10,956
Denominator:
Weighted average shares outstanding—basic (in shares)	52,831	52,206	52,663	52,791
Dilutive effect of stock-based awards (in shares)	1,012	935	1,099	865
Diluted weighted average shares outstanding (in shares)	53,843	53,141	53,762	53,656
Anti-dilutive stock-based awards excluded (in shares)	575	227	506	304
Net income per common share:
Basic (in dollars per share)	$ 0.01	$ 0.07	$ 0.14	$ 0.21
Diluted (in dollars per share)	$ 0.01	$ 0.07	$ 0.14	$ 0.20