Summary of Significant Accounting Policies - Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2014	Dec. 31, 2013
Inventory, Net [Abstract]
Raw materials	$ 15,377	$ 18,651
Work in progress	5,695	10,337
Finished goods	1,988	5,324
Inventories	$ 23,060	$ 34,312

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

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Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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Reference 2: http://www.xbrl.org/2003/role/presentationRef

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Amount before valuation and LIFO reserves of merchandise or goods in the production process expected to be completed within one year or operating cycle, if longer.

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-Name Regulation S-X (SX)

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