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		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Numerator for basic and diluted earnings per share:
Net income	$ 2,276	$ 3,650	$ 6,856	$ 7,113
Denominator:
Weighted average shares outstanding—basic (in shares)	52,736	52,480	52,578	53,087
Dilutive effect of stock-based awards (in shares)	1,034	809	1,145	803
Diluted weighted average shares outstanding (in shares)	53,770	53,289	53,723	53,890
Anti-dilutive stock-based awards excluded (in shares)	544	369	690	520
Net income per common share:
Basic (in dollars per share)	$ 0.04	$ 0.07	$ 0.13	$ 0.13
Diluted (in dollars per share)	$ 0.04	$ 0.07	$ 0.13	$ 0.13