Segment Information (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Mar. 31, 2017
Segment Reporting Information [Abstract]
Net sales	$ 508.3	$ 317.7	$ 1,023.8	$ 664.9
Gross profit	$ 86.1	$ 48.0	$ 174.6	$ 110.3
Gross profit (% of sales)	17.00%	15.10%	17.10%	16.60%
Operating income (loss)	$ 23.5	$ (1.1)	$ 51.1	$ 14.7
Total assets	1,538.0		1,538.0		$ 1,449.5
Operating Segments [Member]
Segment Reporting Information [Abstract]
Net sales	513.9	320.3	1,034.4	671.1
Gross profit	$ 85.9	$ 47.8	$ 174.4	$ 112.7
Gross profit (% of sales)	16.70%	14.90%	16.90%	16.80%
Operating income (loss)	$ 35.0	$ 9.5	$ 72.2	$ 36.8
Operating Segments [Member] \| Americas [Member]
Segment Reporting Information [Abstract]
Net sales	141.9	126.0	290.2	266.0
Gross profit	$ 21.5	$ 15.9	$ 48.0	$ 41.1
Gross profit (% of sales)	15.20%	12.60%	16.60%	15.50%
Operating income (loss)	$ 7.8	$ (1.1)	$ 19.9	$ 8.5
Total assets	289.9		289.9		282.9
Operating Segments [Member] \| Europe [Member]
Segment Reporting Information [Abstract]
Net sales	134.5	123.9	270.8	269.9
Gross profit	$ 19.6	$ 16.4	$ 38.9	$ 41.7
Gross profit (% of sales)	14.50%	13.20%	14.40%	15.40%
Operating income (loss)	$ 8.6	$ 7.0	$ 16.5	$ 22.3
Total assets	311.0		311.0		269.4
Operating Segments [Member] \| Asia [Member]
Segment Reporting Information [Abstract]
Net sales	39.5	24.7	74.9	49.6
Gross profit	$ 7.4	$ 3.7	$ 13.7	$ 8.1
Gross profit (% of sales)	18.90%	14.90%	18.30%	16.20%
Operating income (loss)	$ 4.2	$ 0.8	$ 7.5	$ 2.3
Total assets	125.1		125.1		111.3
Operating Segments [Member] \| Commercial and Industrial Solutions [Member]
Segment Reporting Information [Abstract]
Net sales	149.2	0.0	306.7	0.0
Gross profit	$ 22.5	$ 0.0	$ 47.8	$ 0.0
Gross profit (% of sales)	15.10%	0.00%	15.60%	0.00%
Operating income (loss)	$ 8.1	$ 0.0	$ 18.9	$ 0.0
Total assets	602.0		602.0		576.0
Operating Segments [Member] \| Building HVAC [Member]
Segment Reporting Information [Abstract]
Net sales	48.8	45.7	91.8	85.6
Gross profit	$ 14.9	$ 11.8	$ 26.0	$ 21.8
Gross profit (% of sales)	30.50%	25.80%	28.30%	25.50%
Operating income (loss)	$ 6.3	$ 2.8	$ 9.4	$ 3.7
Total assets	92.7		92.7		85.2
Corporate and Eliminations [Member]
Segment Reporting Information [Abstract]
Net sales	(5.6)	(2.6)	(10.6)	(6.2)
Gross profit	$ 0.2	$ 0.2	$ 0.2	$ (2.4)
Gross profit (% of sales)	0.00%	0.00%	0.00%	0.00%
Operating income (loss)	$ (11.5)	$ (10.6)	$ (21.1)	$ (22.1)
Total assets	$ 117.3		$ 117.3		$ 124.7

Gross profit as a percentage of sales revenue generated by each segment of the entity.

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Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1,2)
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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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