Indebtedness (Details) $ in Millions	6 Months Ended
Indebtedness (Details) $ in Millions	Sep. 30, 2025 USD ($)	Jul. 31, 2025 USD ($)	Mar. 31, 2025 USD ($)
Long-Term Debt [Abstract]
Long-term debt	$ 571.8		$ 343.1
Less: current portion	(43.9)		(44.8)
Less: unamortized debt issuance costs	(2.1)		(1.6)
Total long-term debt	525.8		296.7
Maturities of Long-Term Debt [Abstract]
Remainder of 2026	26.1
2027	43.9
2028	35.6
2029	35.5
2030	10.1
2031 & beyond	420.6
Long-term debt	571.8		343.1
Indebtedness [Abstract]
Short-term debt	12.4		9.3
Level 2
Indebtedness [Abstract]
Fair value of long-term debt	$ 105.3		116.6
Minimum
Indebtedness [Abstract]
Interest coverage ratio	3
Maximum
Indebtedness [Abstract]
Leverage ratio	3.50
Credit agreement
Indebtedness [Abstract]
Capitalized debt issuance costs		$ 2.3
Letters of credit outstanding	$ 6.2
Revolving credit facility
Long-Term Debt [Abstract]
Long-term debt	$ 265.0		30.0
Fiscal year of maturity	2031
Maturities of Long-Term Debt [Abstract]
Long-term debt	$ 265.0		30.0
Indebtedness [Abstract]
Maximum borrowing capacity		400.0
Weighted-average interest rate for variable rate borrowings	5.50%
Available borrowing capacity	$ 128.8
Term loans
Long-Term Debt [Abstract]
Long-term debt	$ 200.0		193.7
Fiscal year of maturity	2031
Maturities of Long-Term Debt [Abstract]
Long-term debt	$ 200.0		193.7
Indebtedness [Abstract]
Maximum borrowing capacity		$ 200.0
Weighted-average interest rate for variable rate borrowings	5.40%
Swingline loans
Indebtedness [Abstract]
Short-term debt	$ 0.0		0.0
5.9% Senior Notes
Long-Term Debt [Abstract]
Long-term debt	$ 87.5		100.0
Interest rate percentage	5.90%
Fiscal year of maturity	2029
Maturities of Long-Term Debt [Abstract]
Long-term debt	$ 87.5		100.0
5.8% Senior Notes
Long-Term Debt [Abstract]
Long-term debt	$ 16.7		16.7
Interest rate percentage	5.80%
Fiscal year of maturity	2027
Maturities of Long-Term Debt [Abstract]
Long-term debt	$ 16.7		16.7
Finance Lease obligations
Long-Term Debt [Abstract]
Long-term debt	2.6		2.7
Maturities of Long-Term Debt [Abstract]
Long-term debt	2.6		2.7
Foreign credit agreements
Indebtedness [Abstract]
Short-term debt	$ 12.4		$ 9.3

MODINE MANUFACTURING CO 10-Q