Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Earnings Per Share [Abstract]
Net earnings attributable to Modine	$ 0.4	$ 8.6	$ 2.7	$ 0.0
Weighted-average shares outstanding - basic (in shares)	52.0	51.3	51.9	51.1
Effect of dilutive securities (in shares)	0.6	0.0	0.6	0.0
Weighted-average shares outstanding - diluted (in shares)	52.6	51.3	52.5	51.1
Earnings per Share [Abstract]
Net earnings per share - basic (in dollars per share)	$ 0.01	$ 0.17	$ 0.05	$ 0
Net earnings per share - diluted (in dollars per share)	$ 0.01	$ 0.17	$ 0.05	$ 0
Stock Options [Member]
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earning per share (in shares)	0.6	1.0	0.6	1.1
Restricted Stock [Member]
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earning per share (in shares)	0.2	0.4	0.2	0.4