Inventories - Summary of Inventories (Detail) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016
Inventory Net [Abstract]
Raw materials	$ 19,871	$ 17,889
Work in process	2,886	3,986
Finished goods	1,269	1,508
Obsolescence allowance	(2,095)	(1,896)
Inventory, net	$ 21,931	$ 21,487

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.6(a))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
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-Section 35
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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

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Amount of valuation reserve for inventory.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 330
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SAB TOPIC 5.BB)
-URI http://asc.fasb.org/extlink&oid=27011343&loc=d3e100047-122729

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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.

+ References

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