Summarize Activity of the Net Product Revenue Allowance and Reserve Categories (Detail) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 48,093	$ 27,198
Provision related to current period sales	45,860	30,426
Provision related to prior period sales	(704)	(1,082)
Credits/payments made for current period sales	(13,161)	(4,416)
Credits/payments made for prior period sales	(24,651)	(20,262)
Ending balance	55,437	31,864
Trade Allowances
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	12,035	3,743
Provision related to current period sales	8,506	6,621
Provision related to prior period sales	(200)	(298)
Credits/payments made for current period sales	(875)	(2,357)
Credits/payments made for prior period sales	(1,336)	(3,107)
Ending balance	18,130	4,602
Rebates, Chargebacks and Discounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	32,064	20,915
Provision related to current period sales	32,947	19,670
Provision related to prior period sales	(435)	(702)
Credits/payments made for current period sales	(10,487)	(727)
Credits/payments made for prior period sales	(20,994)	(15,376)
Ending balance	33,095	23,780
Product Returns
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	1,887	859
Provision related to current period sales	222	1,028
Credits/payments made for prior period sales	(25)	(9)
Ending balance	2,084	1,878
Other Incentives
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	2,107	1,681
Provision related to current period sales	4,185	3,107
Provision related to prior period sales	(69)	(82)
Credits/payments made for current period sales	(1,799)	(1,332)
Credits/payments made for prior period sales	(2,296)	(1,770)
Ending balance	$ 2,128	$ 1,604

Credits/payments made for prior period sales.

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- Definition

Provision related to prior period sales.

+ References

No definition available.

+ Details

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- Definition

Total of allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 4
-Subparagraph (SX 210.12-09)
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

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- Definition

Amount of increase in the allowances and reserves, which consist of the valuation and qualifying accounts that are either netted against the cost of an asset or that reflect a liability established to represent expected future costs, from charges to costs and expenses.

+ References

+ Details

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Total of the deductions in a given period to allowances and reserves, the valuation and qualifying accounts that are either netted against the cost of an asset (in order to value it at its carrying value) or that reflect a liability established to represent expected future costs, representing receivables written off as uncollectible and portions of the reserves utilized, respectively.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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