Leases, Codification Topic 842 (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Mar. 31, 2020	Mar. 31, 2020	Sep. 30, 2019
Leases [Abstract]
Operating Lease, Expense	$ 1.6	$ 3.2
Finance Lease, Right-of-Use Asset, Amortization	0.3	0.6
Total lease expense	1.9	3.8
Operating Lease, Payments		2.9
Finance Lease, Principal Payments		0.7
Operating Lease, Right-of-Use Asset	26.7	26.7	$ 0.0
Finance Lease, Right-of-Use Asset	2.5	2.5
Total right of use assets	29.2	29.2
Operating Lease, Liability, Current	4.4	4.4	0.0
Operating Lease, Liability, Noncurrent	24.0	24.0	$ 0.0
Finance Lease, Liability, Current	1.1	1.1
Finance Lease, Liability, Noncurrent	1.5	1.5
Total lease liabilities	31.0	31.0
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	3.6	3.6
Lessee, Operating Lease, Liability, Payments, Due Year Two	5.3	5.3
Lessee, Operating Lease, Liability, Payments, Due Year Three	4.5	4.5
Lessee, Operating Lease, Liability, Payments, Due Year Four	4.0	4.0
Lessee, Operating Lease, Liability, Payments, Due Year Five	3.9	3.9
Lessee, Operating Lease, Liability, Payments, Due after Year Five	16.0	16.0
Lessee, Operating Lease, Liability, Payments, Due	37.3	37.3
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	8.9	8.9
Operating Lease, Liability	28.4	28.4
Finance Lease, Liability, Payments, Remainder of Fiscal Year	0.8	0.8
Finance Lease, Liability, Payments, Due Year Two	1.1	1.1
Finance Lease, Liability, Payments, Due Year Three	0.7	0.7
Finance Lease, Liability, Payments, Due Year Four	0.4	0.4
Finance Lease, Liability, Payments, Due Year Five	0.0	0.0
Finance Lease, Liability, Payments, Due after Year Five	0.0	0.0
Finance Lease, Liability, Payment, Due	2.9	2.9
Finance Lease, Liability, Undiscounted Excess Amount	0.3	0.3
Finance Lease, Liability	$ 2.6	$ 2.6
Operating Lease, Weighted Average Remaining Lease Term	8 years 1 month 24 days	8 years 1 month 24 days
Finance Lease, Weighted Average Remaining Lease Term	2 years 8 months 4 days	2 years 8 months 4 days
Operating Lease, Weighted Average Discount Rate, Percent	5.71%	5.71%
Finance Lease, Weighted Average Discount Rate, Percent	5.23%	5.23%