Segment Information (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Mar. 31, 2014
Segment Reporting Information [Abstract]
Net sales	$ 363.6us-gaap_Revenues	$ 347.0us-gaap_Revenues	$ 1,133.4us-gaap_Revenues	$ 1,087.0us-gaap_Revenues
Gross profit	59.4us-gaap_GrossProfit	56.8us-gaap_GrossProfit	183.8us-gaap_GrossProfit	175.9us-gaap_GrossProfit
Gross profit as % of sales (in hundredths)	16.40%mod_GrossProfitAsPercentageOfSales	16.40%mod_GrossProfitAsPercentageOfSales	16.20%mod_GrossProfitAsPercentageOfSales	16.20%mod_GrossProfitAsPercentageOfSales
Operating income	15.5us-gaap_OperatingIncomeLoss	0.9us-gaap_OperatingIncomeLoss	47.5us-gaap_OperatingIncomeLoss	30.5us-gaap_OperatingIncomeLoss
Total assets	964.7us-gaap_Assets		964.7us-gaap_Assets		1,032.3us-gaap_Assets
Operating Segments [Member]
Segment Reporting Information [Abstract]
Net sales	367.0	350.9	1,145.9	1,098.6
Gross profit	58.9	56.8	182.7	175.6
Gross profit as % of sales (in hundredths)	16.00%	16.20%	15.90%	16.00%
Operating income	21.0	9.2	66.7	52.4
Operating Segments [Member] \| North America [Member]
Segment Reporting Information [Abstract]
Net sales	131.8	128.9	427.3	423.6
Gross profit	20.3	20.0	69.3	70.5
Gross profit as % of sales (in hundredths)	15.40%	15.50%	16.20%	16.60%
Operating income	6.9	8.7	30.9	34.7
Total assets	217.2		217.2		218.1
Operating Segments [Member] \| Europe [Member]
Segment Reporting Information [Abstract]
Net sales	137.2	140.5	442.2	425.6
Gross profit	14.1	17.2	53.0	51.2
Gross profit as % of sales (in hundredths)	10.30%	12.20%	12.00%	12.00%
Operating income	5.9	(5.3)	20.9	6.0
Total assets	311.3		311.3		367.9
Operating Segments [Member] \| South America [Member]
Segment Reporting Information [Abstract]
Net sales	21.5	27.4	73.9	93.6
Gross profit	2.2	4.5	9.3	16.4
Gross profit as % of sales (in hundredths)	10.00%	16.30%	12.50%	17.50%
Operating income	(1.3)	1.1	(1.2)	6.2
Total assets	62.9		62.9		80.1
Operating Segments [Member] \| Asia [Member]
Segment Reporting Information [Abstract]
Net sales	20.2	17.1	60.0	51.6
Gross profit	2.7	2.0	8.4	6.1
Gross profit as % of sales (in hundredths)	13.60%	11.70%	14.10%	11.80%
Operating income	(0.3)	(0.6)	(0.1)	(2.0)
Total assets	91.1		91.1		92.8
Operating Segments [Member] \| Building HVAC [Member]
Segment Reporting Information [Abstract]
Net sales	56.3	37.0	142.5	104.2
Gross profit	19.6	13.1	42.7	31.4
Gross profit as % of sales (in hundredths)	34.70%	35.50%	30.00%	30.10%
Operating income	9.8	5.3	16.2	7.5
Total assets	148.4		148.4		132.7
Corporate and Eliminations [Member]
Segment Reporting Information [Abstract]
Net sales	(3.4)	(3.9)	(12.5)	(11.6)
Gross profit	0.5	0	1.1	0.3
Gross profit as % of sales (in hundredths)	0.00%	0.00%	0.00%	0.00%
Operating income	(5.5)	(8.3)	(19.2)	(21.9)
Total assets	$ 133.8		$ 133.8		$ 140.7

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

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- Definition

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

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The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

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