The Company and Significant Accounting Policies - Reconciliation of Basic and Diluted Income (Loss) Per Share (Detail) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Earnings Per Share Basic And Diluted [Abstract]
Net income (loss)	$ 9,293	$ 8,057	$ 19,818	$ 21,180
Denominator:
Weighted average common shares outstanding, basic	88,090,143	89,179,192	87,820,029	89,048,459
Basic earnings per share:
Net income (loss) per share, basic	$ 0.11	$ 0.09	$ 0.23	$ 0.24
Net income (loss)	$ 9,293	$ 8,057	$ 19,818	$ 21,180
Denominator:
Weighted average common shares outstanding, basic	88,090,143	89,179,192	87,820,029	89,048,459
Dilutive securities:
Stock options and restricted stock units	2,333,190	2,060,606	2,382,360	2,082,154
Weighted average common shares outstanding, diluted	90,423,333	91,239,798	90,202,389	91,130,613
Diluted earnings per share:
Net income (loss) per share	$ 0.10	$ 0.09	$ 0.22	$ 0.23