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
	Mar. 31, 2017	Mar. 31, 2016
Numerator for basic and diluted earnings per share:
Net income	$ 4,580	$ 3,463
Denominator:
Weighted average shares outstanding—basic (in shares)	52,418	53,693
Dilutive effect of stock-based awards (in shares)	1,259	1,096
Diluted weighted average shares outstanding (in shares)	53,677	54,789
Anti-dilutive stock-based awards excluded (in shares)	676	525
Net income per common share:
Basic (in dollars per share)	$ 0.09	$ 0.06
Diluted (in dollars per share)	$ 0.09	$ 0.06