Summary of Product Revenue Allowances and Reserve Categories (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Valuation Allowance [Line Items]
Beginning balance	$ 610
Provision	5,774	4,059
Payments or credits	(3,857)	(3,449)
Ending balance	2,527	610
Trade Allowances
Valuation Allowance [Line Items]
Beginning balance	18
Provision	723	1,158
Payments or credits	(669)	(1,140)
Ending balance	72	18
Rebates Chargebacks and Discounts
Valuation Allowance [Line Items]
Beginning balance	515
Provision	3,798	2,721
Payments or credits	(2,218)	(2,206)
Ending balance	2,095	515
Other Incentives/ Returns
Valuation Allowance [Line Items]
Beginning balance	77
Provision	1,253	180
Payments or credits	(970)	(103)
Ending balance	$ 360	$ 77

Total of the provision for allowances and reserves in a given period, the valuation and qualifying accounts that are netted against gross revenue or that reflect a liability established to represent expected future costs.

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

-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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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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