Reconciliation of Changes in Inventory Reserve (Detail) (Inventory Valuation Reserve, USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Inventory Valuation Reserve
Schedule Of Inventory [Line Items]
Balance at beginning of year	$ 2,933	$ 2,185	$ 1,127
Expense	2,204	779	1,307
Inventory write off	(154)	(6)	(215)
Adjustment due to currency translation	(181)	(25)	(34)
Balance at end of year	$ 4,802	$ 2,933	$ 2,185

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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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- Definition

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- Definition

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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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