Goodwill and Intangible Assets - Schedule of Changes (Details) - USD ($) $ in Millions	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Goodwill [Roll Forward]
Net carrying amount, beginning of period	$ 1,276.1	$ 1,216.5
Acquisitions	21.3	55.2
Purchase accounting adjustments	8.3
Currency translation adjustment and other	(6.0)	4.4
Net carrying amount, end of period	1,299.7	1,276.1
Operating Segments | Process & Motion Control
Goodwill [Roll Forward]
Net carrying amount, beginning of period	1,102.5	1,068.8
Acquisitions	20.1	29.5
Purchase accounting adjustments	8.1
Currency translation adjustment and other	(5.5)	4.2
Net carrying amount, end of period	1,125.2	1,102.5
Operating Segments | Water Management
Goodwill [Roll Forward]
Net carrying amount, beginning of period	173.6	147.7
Acquisitions	1.2	25.7
Purchase accounting adjustments	0.2
Currency translation adjustment and other	(0.5)	0.2
Net carrying amount, end of period	$ 174.5	$ 173.6