CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2020	Dec. 31, 2019
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Net (loss) earnings	$ (195.4)	$ 1.0	$ (194.9)	$ 4.4
Other comprehensive income (loss):
Foreign currency translation	18.4	14.0	41.2	(3.7)
Defined benefit plans, net of income taxes of $0.3, $0.4, $1.1 and $1.0 million	1.3	1.0	3.8	3.2
Cash flow hedges, net of income taxes of $0, $0.2, $0.5 and ($0.2) million	0.0	0.6	1.4	(0.4)
Total other comprehensive income (loss)	19.7	15.6	46.4	(0.9)
Comprehensive income (loss)	(175.7)	16.6	(148.5)	3.5
Comprehensive (income) loss attributable to noncontrolling interest	(0.7)	0.0	(1.4)	0.2
Comprehensive income (loss) attributable to Modine	$ (176.4)	$ 16.6	$ (149.9)	$ 3.7