Intangible Assets (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Mar. 31, 2018	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Amortized intangible assets [Abstract]
Gross carrying value	$ 150.0	$ 150.0	$ 145.9
Accumulated amortization	(20.1)	(20.1)	(11.8)
Net intangible assets	129.9	129.9	134.1
Amortization expense		9.7	4.1	$ 1.6
2019	9.0	9.0
2020	9.0	9.0
2021	9.0	9.0
2022	9.0	9.0
2023	9.0	9.0
BHVAC [Member]
Amortized intangible assets [Abstract]
Impairment charge	1.2
BHVAC [Member] \| Maximum [Member]
Amortized intangible assets [Abstract]
Annual revenue for discontinued product	1.0
Customer Relationships [Member]
Amortized intangible assets [Abstract]
Gross carrying value	64.2	64.2	60.5
Accumulated amortization	(5.7)	(5.7)	(1.7)
Net intangible assets	58.5	58.5	58.8
Trade Names [Member]
Amortized intangible assets [Abstract]
Gross carrying value	60.6	60.6	58.4
Accumulated amortization	(10.8)	(10.8)	(7.2)
Net intangible assets	49.8	49.8	51.2
Acquired Technology [Member]
Amortized intangible assets [Abstract]
Gross carrying value	25.2	25.2	27.0
Accumulated amortization	(3.6)	(3.6)	(2.9)
Net intangible assets	$ 21.6	$ 21.6	$ 24.1

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(2)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Amount of revenue attributable to disposal group, including, but not limited to, discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 205
-SubTopic 20
-Section 50
-Paragraph 5B
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64827811&loc=SL51721673-107760

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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Balance Type:	credit
Period Type:	instant

- Definition

Amount of amortization expense for assets, excluding financial assets and goodwill, lacking physical substance with a finite life expected to be recognized during the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References