Product Revenue Reserves and Allowances - Summary of Product Revenue Reserve and Allowance Categories (Detail) $ in Thousands	3 Months Ended
Mar. 31, 2016 USD ($)
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	$ 540
Provisions related to sales in the current year	1,474
Adjustments related to sales in the prior year	(127)
Credits and payments made	(905)
Ending balance	982
Trade Allowances [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	138
Provisions related to sales in the current year	354
Credits and payments made	(205)
Ending balance	287
Rebates and Chargeback Discounts [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	362
Provisions related to sales in the current year	1,031
Adjustments related to sales in the prior year	(127)
Credits and payments made	(693)
Ending balance	573
Product Returns [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	32
Provisions related to sales in the current year	74
Credits and payments made	(5)
Ending balance	101
Other Incentives [Member]
Valuation and Qualifying Accounts Disclosure [Line Items]
Beginning balance	8
Provisions related to sales in the current year	15
Credits and payments made	(2)
Ending balance	$ 21

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
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24092-122690

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 09
-Article 12

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+ 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.

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