Segment Information (Details) - USD ($) $ in Millions	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Mar. 31, 2019
Segment Reporting Information [Abstract]
Net sales	$ 529.0	$ 566.1
Gross profit	$ 83.4	$ 94.3
Gross profit (% of sales)	15.80%	16.70%
Operating income	$ 18.1	$ 34.8
Total assets	1,601.3		$ 1,538.0	[1]
Operating lease assets	64.9		61.3
VTS [Member]
Segment Reporting Information [Abstract]
Net sales	326.5	352.8
CIS [Member]
Segment Reporting Information [Abstract]
Net sales	168.8	183.9
BHVAC [Member]
Segment Reporting Information [Abstract]
Net sales	49.0	45.0
Total Segments [Member]
Segment Reporting Information [Abstract]
Net sales	544.3	581.7
Operating Segments [Member]
Segment Reporting Information [Abstract]
Net sales	529.0	566.1
Gross profit	$ 83.0	$ 94.2
Gross profit (% of sales)	15.20%	16.20%
Operating income	$ 31.6	$ 41.9
Operating Segments [Member] | VTS [Member]
Segment Reporting Information [Abstract]
Net sales	312.6	338.3
Gross profit	$ 45.0	$ 54.0
Gross profit (% of sales)	13.80%	15.30%
Operating income	$ 17.3	$ 25.5
Total assets	767.9		749.9	[1]
Operating Segments [Member] | CIS [Member]
Segment Reporting Information [Abstract]
Net sales	167.9	183.5
Gross profit	$ 24.3	$ 28.6
Gross profit (% of sales)	14.40%	15.60%
Operating income	$ 9.0	$ 13.2
Total assets	628.2		604.2	[1]
Operating Segments [Member] | BHVAC [Member]
Segment Reporting Information [Abstract]
Net sales	48.5	44.3
Gross profit	$ 13.7	$ 11.6
Gross profit (% of sales)	27.90%	25.90%
Operating income	$ 5.3	$ 3.2
Total assets	107.0		89.4	[1]
Corporate and Eliminations [Member]
Segment Reporting Information [Abstract]
Net sales	(15.3)	(15.6)
Gross profit	$ 0.4	$ 0.1
Gross profit (% of sales)	0.00%	0.00%
Operating income	$ (13.5)	$ (7.1)
Total assets	98.2		$ 94.5	[1]
Inter-segment Sales [Member]
Segment Reporting Information [Abstract]
Net sales	15.3	15.6
Inter-segment Sales [Member] | VTS [Member]
Segment Reporting Information [Abstract]
Net sales	13.9	14.5
Inter-segment Sales [Member] | CIS [Member]
Segment Reporting Information [Abstract]
Net sales	0.9	0.4
Inter-segment Sales [Member] | BHVAC [Member]
Segment Reporting Information [Abstract]
Net sales	$ 0.5	$ 0.7

[1] The Company adopted new lease accounting guidance and, as a result, recorded $61.3 million of operating lease assets on its consolidated balance sheet on April 1, 2019.  See Note 1 for additional information.