Acquisition of Professional Power Products, Inc. - Estimated Useful Lives of Identifiable Intangible Assets (Detail) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2014
Finite-Lived Intangible Assets [Line Items]
Total identifiable intangible assets	$ 23,500
Backlog [Member]
Finite-Lived Intangible Assets [Line Items]
Total identifiable intangible assets	1,200
Finite lived intangible asset estimated life	18 months
Customer Relationships [Member]
Finite-Lived Intangible Assets [Line Items]
Total identifiable intangible assets	20,600
Finite lived intangible asset estimated life	13 years
Trade Names and Trademarks [Member]
Finite-Lived Intangible Assets [Line Items]
Total identifiable intangible assets	$ 1,700
Finite lived intangible asset estimated life	13 years