Organization and Summary of Significant Accounting Policies - Weighted Average Number of Shares Outstanding and Income Per Share (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Numerator for basic and diluted earnings per share:
Net income	$ 7,205	$ 3,391
Denominator:
Weighted average shares outstanding—basic	53,167	53,190
Dilutive effect of stock-based awards (in shares)	1,346	1,934
Diluted weighted average shares outstanding	54,513	55,124
Anti-dilutive stock-based awards excluded	362	315
Net income (loss) per common share:
Basic (in dollars per share)	$ 0.14	$ 0.06
Diluted (in dollars per share)	$ 0.13	$ 0.06