Basic and Diluted Net Earnings (Loss) Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands		3 Months Ended
		Mar. 31, 2017	Mar. 31, 2016
Earnings Per Share [Abstract]
Net income (loss)		$ 84,090	$ (59,770)
Weighted-average number of shares of common stock and common stock equivalents outstanding:
Weighted-average number of shares of common stock outstanding for computing basic loss per share		54,850	45,697
Dilutive effect of outstanding stock awards and stock options after application of the treasury stock method	[1]	1,162	0
Weighted-average number of shares of common stock and dilutive common stock equivalents outstanding for computing diluted loss per share		56,012	45,697
Basic earnings (loss) per share		$ 1.53	$ (1.31)
Diluted earnings (loss) per share		$ 1.50	$ (1.31)

[1] For the three months ended March 31, 2017, out of money stock options, unvested performance-based RSUs and restricted stock awards whose performance milestones were not achieved and potentially issuable common stock for ESPP to purchase approximately 3.4 million were excluded from the net earnings per share calculation as their effect would have been anti-dilutive. For the three months ended March 31, 2016, stock options, RSAs and SARs to purchase 7.9 million were excluded from the net loss per share calculation as their effect would have been anti-dilutive.