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, 2020	Jun. 30, 2020	Mar. 31, 2020	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Sep. 30, 2020	Sep. 30, 2019
Earnings Per Share Basic And Diluted [Abstract]
Net income (loss)	$ 9,016	$ 2,338	$ (35,592)	$ (12,217)	$ (16,279)	$ 1,424	$ (24,238)	$ (27,072)
Denominator:
Weighted average common shares outstanding, basic	84,185,728			84,765,694			84,208,924	85,404,250
Basic earnings per share:
Net income (loss) per share	$ 0.11			$ (0.14)			$ (0.29)	$ (0.32)
Denominator:
Weighted average common shares outstanding, basic	84,185,728			84,765,694			84,208,924	85,404,250
Dilutive securities:
Stock options and restricted stock units	677,292
Weighted average common shares outstanding, diluted	84,863,020			84,765,694			84,208,924	85,404,250
Diluted earnings per share:
Net income (loss) per share	$ 0.11			$ (0.14)			$ (0.29)	$ (0.32)