Pensions (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Net Periodic Benefit Cost [Abstract]
Net periodic benefit cost	[1]	$ 0.9	$ 0.6	$ 1.7	$ 1.0
Pension [Member]
Net Periodic Benefit Cost [Abstract]
Service cost		0.0	0.0	0.1	0.1
Interest cost		2.4	2.0	4.8	4.0
Expected return on plan assets		(2.6)	(2.9)	(5.2)	(5.8)
Amortization of unrecognized net loss		1.2	1.5	2.3	2.9
Net periodic benefit cost		$ 1.0	$ 0.6	$ 2.0	$ 1.2

[1] Net periodic benefit cost for the Company’s pension and postretirement plans is exclusive of service cost.