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, 2018	Mar. 31, 2017
Numerator for basic and diluted earnings per share:
Net income	$ 12,926	$ 4,580
Denominator:
Weighted average shares outstanding—basic (in shares)	53,119	52,418
Dilutive effect of stock-based awards (in shares)	1,413	1,259
Diluted weighted average shares outstanding (in shares)	54,532	53,677
Anti-dilutive stock-based awards excluded (in shares)	404	676
Net income per common share:
Basic (in dollars per share)	$ 0.24	$ 0.09
Diluted (in dollars per share)	$ 0.24	$ 0.09