Goodwill and Intangible Assets - Schedule of Intangible Assets (Parenthetical) (Detail) - USD ($)			9 Months Ended
	Jul. 27, 2015	May. 22, 2015	Sep. 30, 2015
Torque Systems [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets			$ 3,343,000
Weighted -average amortization period, excluding the indefinite-lived trademark		6 years
Davall [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets	$ 11,044,000
Weighted -average amortization period, excluding the indefinite-lived trademark	10 years
Trademarks [Member] | Torque Systems [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets		$ 473,000
Trademarks [Member] | Davall [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets	$ 1,759,000
Customer Relationships [Member] | Torque Systems [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets		$ 1,535,000
Intangible assets acquired, estimated useful life		5 years
Customer Relationships [Member] | Davall [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets	$ 4,966,000
Intangible assets acquired, estimated useful life	10 years
Patents [Member] | MTE Corporation [Member] | High Power Group [Member]
Other Intangibles [Line Items]
Capitalized legal fees			$ 22,000
Intangible assets acquired, estimated useful life			20 years
Developed Technology [Member] | Torque Systems [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets		$ 1,124,000
Intangible assets acquired, estimated useful life		8 years
Developed Technology [Member] | Davall [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets	$ 3,570,000
Intangible assets acquired, estimated useful life	10 years
License [Member]
Other Intangibles [Line Items]
Intangible assets acquired, estimated useful life			10 years
License [Member] | Davall [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets	$ 426,000
Intangible assets acquired, estimated useful life	10 years
Backlog [Member] | Torque Systems [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets		$ 211,000
Intangible assets acquired, estimated useful life		2 years
Backlog [Member] | Davall [Member]
Other Intangibles [Line Items]
Purchase price allocated to other intangible assets	$ 323,000
Intangible assets acquired, estimated useful life	1 year