Goodwill and Other Intangible Assets - Schedule of Changes in Net Carrying Value of Goodwill by Reportable Segment (Detail) $ in Millions	9 Months Ended
Sep. 30, 2019 USD ($)
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 333.7
Acquisitions of businesses	152.5
Divestiture of business	(1.3)
Foreign currency translation	0.1
Goodwill, ending balance	485.0
Sealing Products
Goodwill [Roll Forward]
Goodwill, beginning balance	311.3
Acquisitions of businesses	152.5
Divestiture of business	(1.3)
Foreign currency translation	(0.1)
Goodwill, ending balance	462.4
Engineered Products
Goodwill [Roll Forward]
Goodwill, beginning balance	10.8
Acquisitions of businesses	0.0
Divestiture of business	0.0
Foreign currency translation	0.1
Goodwill, ending balance	10.9
Power Systems
Goodwill [Roll Forward]
Goodwill, beginning balance	11.6
Acquisitions of businesses	0.0
Divestiture of business	0.0
Foreign currency translation	0.1
Goodwill, ending balance	$ 11.7

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Publisher FASB
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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

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