Product Revenue Reserves and Allowances - Summary of Product Revenue Reserve and Allowance Categories (Detail) $ in Thousands	9 Months Ended
Sep. 30, 2016 USD ($)
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 540
Provisions related to sales in the current year	5,690
Adjustments related to sales in the prior year	(156)
Credits and payments made	(4,365)
Ending balance	1,709
Trade Allowances [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	138
Provisions related to sales in the current year	1,332
Credits and payments made	(978)
Ending balance	492
Rebates and Chargeback Discounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	362
Provisions related to sales in the current year	4,073
Adjustments related to sales in the prior year	(156)
Credits and payments made	(3,354)
Ending balance	925
Product Returns [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	32
Provisions related to sales in the current year	278
Credits and payments made	(26)
Ending balance	284
Other Incentives [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	8
Provisions related to sales in the current year	7
Credits and payments made	(7)
Ending balance	$ 8

Valuation allowances and reserves prior year adjustments.

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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

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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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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

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