Retirement Plans (Net Periodic Benefit Cost) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Defined Benefit Plan, Service Cost	$ 0.4	$ 0.4	$ 1.2	$ 1.2
Defined Benefit Plan, Interest Cost	2.8	3.5	8.4	10.5
Defined Benefit Plan, Expected Return (Loss) on Plan Assets	(4.2)	(4.1)	(12.6)	(12.2)
Amortization of actuarial net loss	0.7	0.5	2.0	1.5
Curtailment/special settlement loss (gain)	0.0	0.0	0.0	1.0
Defined Benefit Plan, Net Periodic Benefit Cost other than Service Cost	(0.7)	(0.1)	(2.2)	0.8
Net periodic benefit cost	$ (0.3)	$ 0.3	$ (1.0)	$ 2.0