Summary of Product Revenue Allowances and Reserve Categories (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Valuation Allowance [Line Items]
Provision	$ 795
Payments or credits	(240)
Balance, March 31, 2013	555
Trade Allowances
Valuation Allowance [Line Items]
Provision	276
Payments or credits	(130)
Balance, March 31, 2013	146
Rebates Chargebacks and Discounts
Valuation Allowance [Line Items]
Provision	501
Payments or credits	(93)
Balance, March 31, 2013	408
Other Incentive
Valuation Allowance [Line Items]
Provision	18
Payments or credits	(17)
Balance, March 31, 2013	$ 1

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 SEC

-Name Regulation S-X (SX)

-Number 210

-Section 09

-Article 12

Reference 2: 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=6881521&loc=d3e24092-122690

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- Definition

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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