Goodwill and Intangible Assets - Schedule of Changes (Details) - USD ($) $ in Millions	12 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Goodwill [Roll Forward]
Goodwill	$ 1,321.9	$ 1,299.7	$ 1,276.1
Acquisitions	26.5	21.3
Purchase accounting adjustments	0.4	8.3
Currency translation adjustment and other	(4.7)	(6.0)
Net carrying amount, end of period	1,321.9	1,299.7
Operating Segments \| Process & Motion Control
Goodwill [Roll Forward]
Goodwill	1,121.4	1,125.2	1,102.5
Acquisitions	0.0	20.1
Purchase accounting adjustments	0.4	8.1
Currency translation adjustment and other	(4.2)	(5.5)
Net carrying amount, end of period	1,121.4	1,125.2
Operating Segments \| Water Management
Goodwill [Roll Forward]
Goodwill	200.5	174.5	$ 173.6
Acquisitions	26.5	1.2
Purchase accounting adjustments	0.0	0.2
Currency translation adjustment and other	(0.5)	(0.5)
Net carrying amount, end of period	$ 200.5	$ 174.5

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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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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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting 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.

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