Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions	3 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Components of basic and diluted earnings per share [Abstract]
Net earnings attributable to Modine	$ 8.0	$ 22.0
Less: Undistributed earnings attributable to unvested shares	0.0	(0.1)
Net earnings available to Modine shareholders	$ 8.0	$ 21.9
Weighted-average shares outstanding - basic (in shares)	50.7	50.3
Effect of dilutive securities (in shares)	0.4	0.9
Weighted-average shares outstanding - diluted (in shares)	51.1	51.2
Earnings per share [Abstract]
Net earnings per share - basic (in dollars per share)	$ 0.16	$ 0.43
Net earnings per share - diluted (in dollars per share)	$ 0.16	$ 0.43
Stock Options [Member]
Antidilutive securities excluded from computation of earning per share [Abstract]
Antidilutive securities excluded from computation of earning per share (in shares)	0.8	0.4