Allowance for Doubtful Accounts Receivable and Sales Returns (Activity in Allowance for Doubtful Accounts Receivable and Sales Returns) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013
Allowance for Doubtful Accounts Receivable
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	$ 1,010
Addition (reduction) to allowance	89
Amounts written off	(12)
Foreign currency translation	(25)
Ending Balance	1,062
Allowance for Sales Returns
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning Balance	653
Addition (reduction) to allowance	(33)
Amounts written off	(8)
Foreign currency translation	0
Ending Balance	$ 612

Valuation Allowances and Currency Translation

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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

+ References

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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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