Accumulated Other Comprehensive Loss (Schedule Of Accumulated Other Comprehensive Loss) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Income (Loss), Foreign Currency Translation Adjustment, Net of Tax	$ 8.0	$ 0.0
Accumulated Other Comprehensive (Income) Loss, Defined Benefit Plan, after Tax	32.7	36.0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Gain (Loss) Arising During Period, Net of Tax	8.0
Other Comprehensive (Income) Loss, Defined Benefit Plan, before Reclassification Adjustment, after Tax	(1.2)
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	9.2
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Reclassification Adjustment from AOCI, Realized upon Sale or Liquidation, Net of Tax	0.0
Other Comprehensive Income (Loss), Foreign Currency Transaction and Translation Adjustment, Net of Tax	8.0	6.3
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, after Tax	3.3
Other Comprehensive Income (Loss), Net of Tax	$ 11.3	$ (3.2)