Summary of Inventories (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended	12 Months Ended
Mar. 31, 2013	Dec. 31, 2012
Inventory, Net [Abstract]
Raw materials	$ 14,579	$ 12,501
Work in process	14,756	12,800
Finished goods	10,423	10,549
Inventory, Gross, Total	39,758	35,850
Less: Progress billings	(2,183)	(4,558)
Total inventories	$ 37,575	$ 31,292

Carrying amount, net of valuation reserves and adjustments, as of the balance sheet date of merchandise or goods held by the company that are readily available for sale.

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Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process.

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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).

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Gross amount of unprocessed items to be consumed in the manufacturing or production process. Also includes purchased parts that will be used as components of a finished product.

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Gross amount of merchandise or goods which are partially completed, are generally comprised of raw materials, labor and factory overhead costs, and which require further materials, labor and overhead to be converted into finished goods, and which generally require the use of estimates to determine percentage complete and pricing.

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Cash received from customers as progress payments on projects that have been partially completed.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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