Selected Statement of Operations Data - Cost of Revenues (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
1) Cost of products sold:
Materials and subcontractors	$ 185,431us-gaap_CostOfGoodsSoldDirectMaterials	$ 125,043us-gaap_CostOfGoodsSoldDirectMaterials	$ 103,417us-gaap_CostOfGoodsSoldDirectMaterials
Labor costs	26,006us-gaap_CostOfGoodsSoldDirectLabor	20,753us-gaap_CostOfGoodsSoldDirectLabor	15,700us-gaap_CostOfGoodsSoldDirectLabor
Overhead and other expenses	12,544us-gaap_CostOfGoodsSoldOverhead	10,906us-gaap_CostOfGoodsSoldOverhead	10,484us-gaap_CostOfGoodsSoldOverhead
Cost of products sold	223,981us-gaap_CostOfGoodsSold	156,702us-gaap_CostOfGoodsSold	129,601us-gaap_CostOfGoodsSold
2) Cost of services rendered:
Materials consumed	51,167us-gaap_CostOfServicesDirectMaterials	44,088us-gaap_CostOfServicesDirectMaterials	45,704us-gaap_CostOfServicesDirectMaterials
Labor costs	37,135us-gaap_CostOfServicesDirectLabor	34,117us-gaap_CostOfServicesDirectLabor	35,954us-gaap_CostOfServicesDirectLabor
Overhead and other expenses	17,270us-gaap_CostOfServicesOverhead	13,548us-gaap_CostOfServicesOverhead	22,188us-gaap_CostOfServicesOverhead
Cost of services rendered	$ 105,572us-gaap_CostOfServices	$ 91,753us-gaap_CostOfServices	$ 103,846us-gaap_CostOfServices

Total costs related to goods produced and sold during the reporting period.

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

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