Acquisitions - Additional Information (Detail) - Stromag [Member] - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2017	Sep. 30, 2017
Business Acquisition [Line Items]
Reduction in purchase price	$ 2.9
Customer Relationships [Member]
Business Acquisition [Line Items]
Amortization period		15 years

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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