Inventories (Detail) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Inventory Disclosure [Line Items]
Raw materials and purchased parts for assembly	$ 9,006	$ 7,030
Self-manufactured assembly parts and finished products	8,893	5,508
Total	$ 17,899	$ 12,538

Inventory Disclosure [Line Items]

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- Definition

The aggregated amount of merchandise or goods held by the entity that are readily available for future sale and items held by the entity which are partially complete or in the process of being readied for future sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

-Section 02

-Paragraph 6

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- Definition

Carrying amount (lower of cost or market) as of the balance sheet date of inventories less all valuation and other allowances. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Aggregated amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 6

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-Article 5

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-Name Accounting Standards Codification

-Topic 210

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