Leases, Codification Topic 842 (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
Jun. 30, 2020	Jun. 30, 2020	Sep. 30, 2019
Leases [Abstract]
Operating Lease, Expense	$ 1.6	$ 4.7
Finance Lease, Right-of-Use Asset, Amortization	0.3	1.0
Total lease expense	1.9	5.7
Operating Lease, Payments		4.5
Finance Lease, Principal Payments		1.0
Operating Lease, Right-of-Use Asset	26.3	26.3	$ 0.0
Finance Lease, Right-of-Use Asset	2.6	2.6
Total right of use assets	28.9	28.9
Operating Lease, Liability, Current	4.2	4.2	0.0
Operating Lease, Liability, Noncurrent	23.8	23.8	$ 0.0
Finance Lease, Liability, Current	1.2	1.2
Finance Lease, Liability, Noncurrent	1.6	1.6
Total lease liabilities	30.8	30.8
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	1.6	1.6
Lessee, Operating Lease, Liability, Payments, Due Year Two	5.5	5.5
Lessee, Operating Lease, Liability, Payments, Due Year Three	4.7	4.7
Lessee, Operating Lease, Liability, Payments, Due Year Four	4.3	4.3
Lessee, Operating Lease, Liability, Payments, Due Year Five	4.1	4.1
Lessee, Operating Lease, Liability, Payments, Due after Year Five	16.1	16.1
Lessee, Operating Lease, Liability, Payments, Due	36.3	36.3
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	8.3	8.3
Operating Lease, Liability	28.0	28.0
Finance Lease, Liability, Payments, Remainder of Fiscal Year	0.4	0.4
Finance Lease, Liability, Payments, Due Year Two	1.2	1.2
Finance Lease, Liability, Payments, Due Year Three	0.8	0.8
Finance Lease, Liability, Payments, Due Year Four	0.5	0.5
Finance Lease, Liability, Payments, Due Year Five	0.1	0.1
Finance Lease, Liability, Payments, Due after Year Five	0.0	0.0
Finance Lease, Liability, Payment, Due	3.0	3.0
Finance Lease, Liability, Undiscounted Excess Amount	0.2	0.2
Finance Lease, Liability	$ 2.8	$ 2.8
Operating Lease, Weighted Average Remaining Lease Term	7 years 11 months 26 days	7 years 11 months 26 days
Finance Lease, Weighted Average Remaining Lease Term	2 years 7 months 17 days	2 years 7 months 17 days
Operating Lease, Weighted Average Discount Rate, Percent	5.65%	5.65%
Finance Lease, Weighted Average Discount Rate, Percent	5.03%	5.03%

Total lease expense

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Total lease liabilities

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Total right of use assets

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Present value of lessee's discounted obligation for lease payments from finance lease.

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-Name Accounting Standards Codification
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-Section 50
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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for finance lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for finance lease.

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Amount of cash outflow for principal payment on finance lease.

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Amount, after accumulated amortization, of right-of-use asset from finance lease.

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Amount of amortization expense attributable to right-of-use asset from finance lease.

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Weighted average discount rate for finance lease calculated at point in time.

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Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Amount of operating lease expense. Excludes sublease income.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Amount of lessee's right to use underlying asset under operating lease.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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