The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Goodwill and Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Mar. 31, 2018
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 173.8
Effect of exchange rate changes	(3.4)
Goodwill, ending balance	170.4
Amortized intangible assets [Abstract]
Gross carrying value	146.4		$ 150.0
Accumulated amortization	(21.7)		(20.1)
Net intangible assets	124.7		129.9
Amortization expense	2.3	$ 2.4
Estimated future amortization expense [Abstract]
2020	9.0
2021	9.0
2022	8.0
2023	8.0
2024	8.0
VTS [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	0.5
Effect of exchange rate changes	0.0
Goodwill, ending balance	0.5
BHVAC [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	15.0
Effect of exchange rate changes	(0.7)
Goodwill, ending balance	14.3
CIS [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	158.3
Effect of exchange rate changes	(2.7)
Goodwill, ending balance	155.6
Customer Relationships [Member]
Amortized intangible assets [Abstract]
Gross carrying value	62.5		64.2
Accumulated amortization	(6.4)		(5.7)
Net intangible assets	56.1		58.5
Trade Names [Member]
Amortized intangible assets [Abstract]
Gross carrying value	59.5		60.6
Accumulated amortization	(11.3)		(10.8)
Net intangible assets	48.2		49.8
Acquired Technology [Member]
Amortized intangible assets [Abstract]
Gross carrying value	24.4		25.2
Accumulated amortization	(4.0)		(3.6)
Net intangible assets	$ 20.4		$ 21.6