Pensions (Details) - USD ($) $ in Millions		3 Months Ended
		Jun. 30, 2018	Jun. 30, 2017
Components of net periodic benefit cost [Abstract]
Net periodic benefit cost	[1]	$ 0.7	$ 0.8
Pension [Member]
Components of net periodic benefit cost [Abstract]
Service cost		0.1	0.1
Interest cost		2.4	2.5
Expected return on plan assets		(3.0)	(3.0)
Amortization of unrecognized net loss		1.4	1.4
Net periodic benefit cost		0.9	1.0
Pension [Member] | United States [Member]
Defined benefit plan, plan assets [Abstract]
Employer contributions		$ 1.9	$ 1.9

[1] Represents net periodic benefit cost, exclusive of service cost, for the Company's pension and postretirement plans.