Amounts Reclassified out of AOCI (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Total revenues	$ 372,845	$ 317,448	$ 746,292	$ 621,193
LOSS FROM OPERATIONS	(25,263)	(38,812)	(69,635)	(59,020)
Other income	2,849	543	2,677	4,015
Benefit from income taxes	(12,385)	(8,713)	(19,040)	(16,729)
NET LOSS	(16,792)	(36,833)	(60,941)	(53,123)
Net Product Revenues
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Total revenues	367,786	315,926	736,885	618,116
Reclassified out of Accumulated Other Comprehensive Income
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Benefit from income taxes	0	0	0	(1,181)
NET LOSS	(2,659)	695	(8,444)	5,282
Reclassified out of Accumulated Other Comprehensive Income | Gains (losses) on Cash Flow Hedges
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
LOSS FROM OPERATIONS	(2,659)	695	(8,444)	3,211
Reclassified out of Accumulated Other Comprehensive Income | Gains (losses) on Cash Flow Hedges | Forward Foreign Currency Exchange Contracts
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Operating expenses	1,403	(424)	3,264	(1,450)
Reclassified out of Accumulated Other Comprehensive Income | Gains (losses) on Cash Flow Hedges | Net Product Revenues | Forward Foreign Currency Exchange Contracts
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Total revenues	(4,062)	1,119	(11,708)	4,661
Reclassified out of Accumulated Other Comprehensive Income | Gain on Sale of Available-for-Sale Debt Securities
Reclassification Adjustment Out Of Accumulated Other Comprehensive Income [Line Items]
Other income	0	0	0	3,252
Total gain on available-for-sale debt securities	$ 0	$ 0	$ 0	$ 2,071