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, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2019	Sep. 30, 2018
Numerator for basic and diluted earnings per share:
Net income	$ 6,104	$ 738	$ 6,419	$ 5,711	$ 8,485	$ 12,926	$ 13,261	$ 27,122
Denominator:
Weighted average shares outstanding—basic (in shares)	59,278			58,340			59,128	55,681
Dilutive effect of stock-based awards (in shares)	781			1,465			810	1,573
Diluted weighted average shares outstanding (in shares)	60,059			59,805			59,938	57,254
Anti-dilutive stock-based awards excluded (in shares)	12,477			6,793			12,546	6,760
Net income per common share:
Basic (in dollars per share)	$ 0.10			$ 0.10			$ 0.22	$ 0.49
Diluted (in dollars per share)	$ 0.10			$ 0.10			$ 0.22	$ 0.47