Summarizes Activity of the Net Product Revenue Allowance and Reserve Categories (Detail) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 15,796	$ 7,090
Provision related to current period sales	71,318	37,944
Provision related to prior period sales	(489)	(244)
Credits/payments made for current period sales	(40,110)	(25,143)
Credits/payments made for prior period sales	(14,203)	(6,383)
Ending balance	32,312	13,264
Trade Receivables
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	4,296	2,207
Provision related to current period sales	15,823	10,104
Provision related to prior period sales	(87)	(174)
Credits/payments made for current period sales	(11,086)	(6,729)
Credits/payments made for prior period sales	(4,180)	(2,043)
Ending balance	4,766	3,365
Rebates Chargebacks And Discounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	9,881	3,610
Provision related to current period sales	46,553	21,633
Provision related to prior period sales	(402)	(70)
Credits/payments made for current period sales	(22,236)	(14,194)
Credits/payments made for prior period sales	(8,492)	(3,522)
Ending balance	25,304	7,457
Allowance for Sales Returns
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	535	481
Provision related to current period sales	403	231
Credits/payments made for prior period sales	(247)	(26)
Ending balance	691	686
Other Incentive Programs
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	1,084	792
Provision related to current period sales	8,539	5,976
Credits/payments made for current period sales	(6,788)	(4,220)
Credits/payments made for prior period sales	(1,284)	(792)
Ending balance	$ 1,551	$ 1,756

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- Definition

Provision Related to Prior Period Sales

+ References

No definition available.

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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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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.

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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.

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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.

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