Pensions (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost	[1]	$ 0.7	$ 0.6	$ 2.1	$ 2.0
Pension [Member]
Components of net periodic benefit cost [Abstract]
Service cost		0.1	0.2	0.3	0.4
Interest cost		2.3	2.4	6.8	7.2
Expected return on plan assets		(3.0)	(3.1)	(8.9)	(9.2)
Amortization of unrecognized net loss		1.5	1.4	4.5	4.2
Net periodic benefit cost		$ 0.9	$ 0.9	2.7	2.6
Pension [Member] | United States [Member]
Defined benefit plan, plan assets [Abstract]
Employer contributions				$ 2.6	$ 4.6

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