Summarizes Activity of the Net Product Revenue Allowance and Reserve Categories (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2016	Jun. 30, 2015
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 15,796	$ 7,090
Provision related to current period sales	44,864	21,968
Provision related to prior period sales	(553)	(157)
Credits/payments made for current period sales	(20,075)	(12,202)
Credits/payments made for prior period sales	(14,187)	(6,376)
Ending balance	25,845	10,323
Trade Receivables
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	4,296	2,207
Provision related to current period sales	10,048	6,044
Provision related to prior period sales	(87)	(113)
Credits/payments made for current period sales	(6,415)	(3,810)
Credits/payments made for prior period sales	(4,180)	(2,039)
Ending balance	3,662	2,289
Rebates Chargebacks And Discounts
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	9,881	3,610
Provision related to current period sales	28,945	11,957
Provision related to prior period sales	(466)	(44)
Credits/payments made for current period sales	(10,750)	(6,243)
Credits/payments made for prior period sales	(8,497)	(3,531)
Ending balance	19,113	5,749
Allowance for Sales Returns
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	535	481
Provision related to current period sales	257	276
Credits/payments made for prior period sales	(226)	(14)
Ending balance	566	743
Other Incentive Programs
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	1,084	792
Provision related to current period sales	5,614	3,691
Credits/payments made for current period sales	(2,910)	(2,149)
Credits/payments made for prior period sales	(1,284)	(792)
Ending balance	$ 2,504	$ 1,542

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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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