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, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share Basic And Diluted [Abstract]
Net income	$ 157,208	$ 5,415	$ 163,321	$ 13,402
Denominator:
Weighted average common shares outstanding, basic	90,517,492	89,590,135	90,370,679	89,208,732
Basic earnings per share:
Net income per share, basic	$ 1.74	$ 0.06	$ 1.81	$ 0.15
Denominator:
Weighted average common shares outstanding, basic	90,517,492	89,590,135	90,370,679	89,208,732
Dilutive securities:
Stock options and restricted stock units	1,643,616	1,899,840	1,615,267	1,980,226
Weighted average common shares outstanding, diluted	92,161,108	91,489,975	91,985,946	91,188,958
Diluted earnings per share:
Net income per share, diluted	$ 1.71	$ 0.06	$ 1.78	$ 0.15