Acquisition, Luvata HTS (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		12 Months Ended
	Nov. 30, 2016	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Allocation of Purchase Price for Acquisition [Abstract]
Goodwill		$ 168.5	$ 173.8	$ 165.1
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Interest expense		$ 24.8	25.6	17.2
Acquisition-related Costs [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Amortization and depreciation expense				13.0
Interest expense				14.0
Acquisition related transaction costs				8.6
Fair Value Adjustment to Inventory [Member]
Business Acquisition, Pro Forma Information, Nonrecurring Adjustment [Line Items]
Acquisition related transaction costs				4.3
Luvata HTS [Member]
Business Acquisition [Line Items]
Acquired ownership interest by the entity	100.00%
Purchase price allocation, net of cash acquired	$ 388.2
Allocation of Purchase Price for Acquisition [Abstract]
Cash and cash equivalents	27.4
Trade accounts receivable	86.1
Inventories	55.0
Property, plant and equipment	120.4
Intangible assets	130.2
Goodwill	151.9
Other assets	39.1
Accounts payable	(73.7)
Accrued compensation and employee benefits	(24.3)
Deferred income taxes	(39.5)
Pensions	(14.3)
Other liabilities	(42.7)
Purchase price	$ 415.6
Pro Forma Information [Abstract]
Net sales				1,881.6
Net earnings attributable to Modine				$ 35.8
Net earnings per share attributable to Modine Shareholders [Abstract]
Basic (in dollars per share)				$ 0.72
Diluted (in dollars per share)				$ 0.71
Luvata HTS [Member] | Selling, General and Administrative Expenses [Member]
Business Acquisition [Line Items]
Cost related to acquisition and integration			$ 4.3	$ 14.8
Luvata HTS [Member] | Common Stock [Member]
Business Acquisition [Line Items]
Shares issued to acquire Luvata HTS (in shares)	2.2
Value of shares issued to acquire Luvata HTS	$ 24.3