Effect of Derivative Instruments (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Derivative Instruments, Gain (Loss) [Line Items]
Net product revenues	$ 1,704,048	$ 1,491,212	$ 1,313,646
Operating expenses as reported	1,804,505	1,614,736	1,328,346
Product
Derivative Instruments, Gain (Loss) [Line Items]
Net product revenues	1,661,043	$ 1,470,356	$ 1,270,445
Derivatives Designated As Hedging Instruments
Derivative Instruments, Gain (Loss) [Line Items]
Amount of Gain (Loss) Recognized in Other Comprehensive Income	25,266
Derivatives Designated As Hedging Instruments | Operating Expenses | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Derivative Instruments, Gain (Loss) [Line Items]
Cash Flow Hedge Gains (Losses) Reclassified into Earnings	(3,453)
Derivatives Designated As Hedging Instruments | Product | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Derivative Instruments, Gain (Loss) [Line Items]
Cash Flow Hedge Gains (Losses) Reclassified into Earnings	17,672
Not Designated as Hedging Instrument
Derivative Instruments, Gain (Loss) [Line Items]
Net gain (loss) recognized in net loss	$ (5,259)