CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	12 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2019
CONSOLIDATED STATEMENTS OF OPERATIONS [Abstract]
Net sales	$ 1,808.4	$ 1,975.5	$ 2,212.7
Cost of sales	1,515.0	1,668.0	1,847.2
Gross profit	293.4	307.5	365.5
Selling, general and administrative expenses	210.9	249.6	244.1
Restructuring expenses	13.4	12.2	9.6
Impairment charges	166.8	8.6	0.4
(Gain) loss on sale of assets	0.0	(0.8)	1.7
Operating (loss) income	(97.7)	37.9	109.7
Interest expense	(19.4)	(22.7)	(24.8)
Other expense - net	(2.2)	(4.8)	(4.1)
(Loss) earnings before income taxes	(119.3)	10.4	80.8
(Provision) benefit for income taxes	(90.2)	(12.4)	5.1
Net (loss) earnings	(209.5)	(2.0)	85.9
Net earnings attributable to noncontrolling interest	(1.2)	(0.2)	(1.1)
Net (loss) earnings attributable to Modine	$ (210.7)	$ (2.2)	$ 84.8
Net (loss) earnings per share attributable to Modine shareholders:
Basic (in dollars per share)	$ (4.11)	$ (0.04)	$ 1.67
Diluted (in dollars per share)	$ (4.11)	$ (0.04)	$ 1.65
Weighted-average shares outstanding:
Basic (in shares)	51.3	50.8	50.5
Diluted (in shares)	51.3	50.8	51.3