Goodwill and Intangible Assets - Changes in Goodwill (Detail) $ in Millions	3 Months Ended
Mar. 31, 2020 USD ($)
Goodwill [Roll Forward]
Net goodwill, Beginning balance	$ 1,694.9
Goodwill impairment charge	(139.1)
Impact of changes in foreign currency	(27.5)
Net goodwill, ending balance	1,528.3
Power Transmission Technologies [Member]
Goodwill [Roll Forward]
Net goodwill, Beginning balance	410.1
Impact of changes in foreign currency	(3.4)
Net goodwill, ending balance	406.7
Automation & Specialty [Member]
Goodwill [Roll Forward]
Net goodwill, Beginning balance	1,284.8
Goodwill impairment charge	(139.1)
Impact of changes in foreign currency	(24.1)
Net goodwill, ending balance	$ 1,121.6

Goodwill foreign currency divestiture and other adjustments.

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- Definition

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.

+ References

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Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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