Retirement and Postretirement Plans (Defined Benefit Plans) (Details) - USD ($) $ in Millions	3 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Defined Benefit Plan Disclosure [Line Items]
Interest cost	$ 1.9	$ 2.5
Expected return on plan assets	(3.0)	(3.7)
Defined Benefit Plan, Amortization of Prior Service Cost (Credit)	0.0	0.1
Amortization of net loss	1.5	1.5
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Remeasurement due to Settlement	3.3
Net pension expense	5.0	1.6
Defined contribution savings plans expense	7.8	6.2
Cost of Goods and Service Benchmark [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	0.5	0.4
Selling, General and Administrative Expenses [Member]
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0.8	$ 0.8