Acquisitions - Summary of Supplemental Pro Forma Information (Detail) - Professional Power Products, Inc. [Member] - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Net sales	$ 93,972	$ 292,776	$ 249,265
Net income	$ 7,148	$ 12,574	$ 12,792
Earnings per share, basic	$ 0.66	$ 1.16	$ 1.20
Earnings per share, diluted	$ 0.56	$ 0.41	$ 1.04

The pro forma basic net income per share for a period as if the business combination or combinations had been completed at the beginning of a period.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (h)(2)-(3)

-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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