Goodwill and Intangible Assets (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended	9 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Sep. 30, 2017	Dec. 31, 2017		Dec. 31, 2016	Mar. 31, 2017
Goodwill [Roll Forward]
Goodwill, beginning balance				$ 165.1	$ 165.1
Acquisition				1.3	1.3	[1]
Effect of exchange rate changes					5.8
Goodwill, ending balance		$ 172.2			172.2
Amortized intangible assets [Abstract]
Gross carrying value		152.1			152.1			$ 145.9
Accumulated amortization		(19.6)			(19.6)			(11.8)
Net intangible assets		132.5			132.5			134.1
Amortization expense		2.5	$ 1.1		7.3		$ 1.9
Estimated future amortization expense [Abstract]
Remainder of 2018		2.4			2.4
2019		9.6			9.6
2020		9.5			9.5
2021		8.9			8.9
2022		8.7			8.7
2023 & Beyond		93.4			93.4
Asia [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance				0.5	0.5
Acquisition	[1]				0.0
Effect of exchange rate changes					0.0
Goodwill, ending balance		0.5			0.5
Building HVAC [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance				13.7	13.7
Acquisition	[1]				0.0
Effect of exchange rate changes					0.8
Goodwill, ending balance		14.5			14.5
CIS [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance				$ 150.9	150.9
Acquisition	[1]				1.3
Effect of exchange rate changes					5.0
Goodwill, ending balance		157.2			157.2
Customer Relationships [Member]
Amortized intangible assets [Abstract]
Gross carrying value		63.6			63.6			60.5
Accumulated amortization		(4.7)			(4.7)			(1.7)
Net intangible assets		58.9			58.9			58.8
Trade Names [Member]
Amortized intangible assets [Abstract]
Gross carrying value		60.1			60.1			58.4
Accumulated amortization		(9.8)			(9.8)			(7.2)
Net intangible assets		50.3			50.3			51.2
Acquired Technology [Member]
Amortized intangible assets [Abstract]
Gross carrying value		28.4			28.4			27.0
Accumulated amortization		(5.1)			(5.1)			(2.9)
Net intangible assets		$ 23.3			$ 23.3			$ 24.1

[1] During the first six months of fiscal 2018, the Company recorded a $1.3 million increase to goodwill as a result of measurement period adjustments made in connection with purchase accounting for the acquisition of Luvata HTS. See Note 2 for additional information.