Gross-to-Net Product Sales - Reconciliation of Gross-to-Net Product Sales (Detail) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Revenue, Net [Abstract]
Gross product sales	$ 61,513	$ 44,713	$ 175,963	$ 160,111
Commercial rebates and government chargebacks	(26,167)	(12,515)	(67,389)	(44,364)
Data and distribution fees, GPO fees, and inventory management fees	(4,234)	(3,503)	(10,235)	(12,709)
Prompt pay discounts	(300)	(15)	(380)	(16)
Product returns allowance	(540)	(223)	(1,558)	(1,008)
Net product sales	$ 30,272	$ 28,457	$ 96,401	$ 102,014

Data Distribution and GPO Fees

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- Definition

Rebates And Charge backs

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No definition available.

+ Details

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- Definition

Aggregate cash discounts given by the entity for goods sold to customers including, but not limited to, early payments of accounts due. For example, selling terms of "2/10, net 30" entitle a customer to a 2% discount for prompt payment within 10 days, otherwise full payment is expected in 30 days. Discounts are a deduction from gross revenue in arriving at net revenue.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(a))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Total deduction from sales during the period arising from goods returned by customers (other than under warranty provisions) and price reductions (allowance, price protection agreements) given by the entity. Returns and allowances are a deduction from gross revenue in arriving at net revenue.

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- Definition

Aggregate revenue during the period from sale of goods in the normal course of business, before deducting returns, allowances and discounts.

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+ Details

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- Definition

Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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- References

No definition available.

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