Segment Information (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2017
Segment Reporting Information [Abstract]
Net sales		$ 512.7	$ 349.8	$ 1,536.5	$ 1,014.7
Gross profit		$ 85.4	$ 59.0	$ 260.0	$ 169.3
Gross profit (% of sales)		16.70%	16.90%	16.90%	16.70%
Operating income (loss)		$ 13.9	$ 6.7	$ 65.0	$ 21.4
Total assets		1,502.2		1,502.2		$ 1,449.5
Commercial and Industrial Solutions [Member]
Segment Reporting Information [Abstract]
Restructuring and asset impairment charges		9.5
Operating Segments [Member]
Segment Reporting Information [Abstract]
Net sales		518.9	353.7	1,553.3	1,024.8
Gross profit		$ 85.4	$ 61.7	$ 259.8	$ 174.4
Gross profit (% of sales)		16.40%	17.50%	16.70%	17.00%
Operating income (loss)		$ 24.9	$ 23.3	$ 97.1	$ 60.1
Operating Segments [Member] | Americas [Member]
Segment Reporting Information [Abstract]
Net sales		140.5	123.4	430.7	389.4
Gross profit		$ 21.7	$ 18.4	$ 69.7	$ 59.5
Gross profit (% of sales)		15.40%	14.90%	16.20%	15.30%
Operating income (loss)		$ 8.9	$ 5.7	$ 28.8	$ 14.2
Total assets		275.9		275.9		282.9
Operating Segments [Member] | Europe [Member]
Segment Reporting Information [Abstract]
Net sales		134.6	119.8	405.4	389.7
Gross profit		$ 17.9	$ 18.6	$ 56.8	$ 60.3
Gross profit (% of sales)		13.30%	15.50%	14.00%	15.50%
Operating income (loss)		$ 6.3	$ 8.6	$ 22.8	$ 30.9
Total assets		308.1		308.1		269.4
Operating Segments [Member] | Asia [Member]
Segment Reporting Information [Abstract]
Net sales		42.8	28.6	117.7	78.2
Gross profit		$ 8.2	$ 5.0	$ 21.9	$ 13.1
Gross profit (% of sales)		19.00%	17.60%	18.60%	16.70%
Operating income (loss)		$ 5.1	$ 2.6	$ 12.6	$ 4.9
Total assets		132.5		132.5		111.3
Operating Segments [Member] | Commercial and Industrial Solutions [Member]
Segment Reporting Information [Abstract]
Net sales	[1]	144.9	34.7	451.6	34.7
Gross profit	[1]	$ 18.6	$ 4.4	$ 66.4	$ 4.4
Gross profit (% of sales)	[1]	12.90%	12.70%	14.70%	12.70%
Operating income (loss)	[1]	$ (4.6)	$ (0.3)	$ 14.3	$ (0.3)
Total assets		606.8		606.8		576.0
Operating Segments [Member] | Building HVAC [Member]
Segment Reporting Information [Abstract]
Net sales		56.1	47.2	147.9	132.8
Gross profit		$ 19.0	$ 15.3	$ 45.0	$ 37.1
Gross profit (% of sales)		33.80%	32.40%	30.40%	28.00%
Operating income (loss)		$ 9.2	$ 6.7	$ 18.6	$ 10.4
Total assets		88.8		88.8		85.2
Corporate and Eliminations [Member]
Segment Reporting Information [Abstract]
Net sales		(6.2)	(3.9)	(16.8)	(10.1)
Gross profit		$ 0.0	$ (2.7)	$ 0.2	$ (5.1)
Gross profit (% of sales)		0.00%	0.00%	0.00%	0.00%
Operating income (loss)		$ (11.0)	$ (16.6)	$ (32.1)	$ (38.7)
Total assets	[2]	$ 90.1		$ 90.1		$ 124.7

[1] The Company acquired Luvata HTS on November 30, 2016 and began operating the business as its CIS segment. As the Company has consolidated CIS financial results since the acquisition date, the three and nine months ended December 31, 2016 included one month of financial results from CIS operations. During the three months ended December 31, 2017, the Company recorded restructuring expenses and an impairment charge totaling $9.5 million within the CIS segment associated with the closure of a manufacturing facility in Austria. See Note 6 for additional information.

[2] The decrease in total assets at Corporate was primarily due to a decrease in deferred tax assets resulting from the impact of tax reform in the U.S. See Note 8 for additional information regarding the reduction in the corporate tax rate in the U.S.