Goodwill (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Mar. 31, 2015	Mar. 31, 2014
Goodwill [Line Items]
Beginning balance	$ 28.7us-gaap_Goodwill	$ 28.7us-gaap_Goodwill
Impairment charge	(7.8)
Effect of exchange rate changes	(4.7)us-gaap_GoodwillTranslationAdjustments	0us-gaap_GoodwillTranslationAdjustments
Ending balance	16.2us-gaap_Goodwill	28.7us-gaap_Goodwill
South America [Member]
Goodwill [Line Items]
Beginning balance	10.9	12.2
Impairment charge	(7.8)
Effect of exchange rate changes	(3.1)	(1.3)
Ending balance	0	10.9
Asia [Member]
Goodwill [Line Items]
Beginning balance	0.5	0.5
Impairment charge	0
Effect of exchange rate changes	0	0
Ending balance	0.5	0.5
Building HVAC [Member]
Goodwill [Line Items]
Beginning balance	17.3	16.0
Impairment charge	0
Effect of exchange rate changes	(1.6)	1.3
Ending balance	15.7	17.3
Europe [Member]
Goodwill [Line Items]
Impairment charge		8.7
North America [Member]
Goodwill [Line Items]
Impairment charge	$ 23.8

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.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 45

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

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- Definition

Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a,h)

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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- Definition

Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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