Accumulated Other Comprehensive Income - Amounts Reclassified out of Accumulated Other Comprehensive Income (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net product revenues	$ 429,485	$ 387,763	$ 931,554	$ 788,508
Total gain (loss) on cash flow hedges	(40,945)	(41,354)	64,016	(95,305)
Net product revenues
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net product revenues	419,032	379,075	908,075	773,558
Amount Reclassified from AOCI Gain (Loss) | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Total gain (loss) on cash flow hedges	6,493	3,512	11,149	4,478
Amount Reclassified from AOCI Gain (Loss) | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Forward contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Operating expenses	(1,786)	(768)	(3,459)	(497)
Amount Reclassified from AOCI Gain (Loss) | Accumulated Gain (Loss), Net, Cash Flow Hedge, Parent | Net product revenues | Forward contracts
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net product revenues	$ 8,279	$ 4,280	$ 14,608	$ 4,975