Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Earnings Per Share [Abstract]
Net earnings (loss) attributable to Modine	$ 2.3	$ (8.6)
Weighted-average shares outstanding - basic (in shares)	51.8	50.9
Effect of dilutive securities (in shares)	0.7	0.0
Weighted-average shares outstanding - diluted (in shares)	52.5	50.9
Earnings (Loss) per Share [Abstract]
Net earnings (loss) per share - basic (in dollars per share)	$ 0.04	$ (0.17)
Net earnings (loss) per share - diluted (in dollars per share)	$ 0.04	$ (0.17)
Stock Options [Member]
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earning per share (in shares)	0.3	1.4
Restricted Stock [Member]
Earnings Per Share [Abstract]
Antidilutive securities excluded from computation of earning per share (in shares)	0.2	0.4