Derivative Financial Instruments (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Derivatives, Fair Value
Derivative, notional amount		$ 350.0
AOCI, cumulative net hedging (loss) gain, before tax		(7.1)
AOCI, cumulative net hedging (loss) gain, after tax		(6.7)
Derivative liability, current	$ 0.0	4.7
Derivative liability, noncurrent		1.1
Derivative liability		5.8
Derivative loss (gain), net	4.4	2.3	$ 2.6
Derivative cash settlements paid, net	(2.0)	$ (4.8)	(1.8)
Payments on interest rate swaps	1.5
Derivative Liability, Statement of Financial Position [Extensible Enumeration]		Other liabilities
Term Loan
Derivatives, Fair Value
Write-off of Tax Benefit related to Interest Rate Swaps, previously recorded in AOCI	(0.4)
Write-off of Interest Rate Swap Loss, previously recorded in AOCI	6.1
Income Tax Expense Benefit \| Term Loan
Derivatives, Fair Value
Write-off of Tax Benefit related to Interest Rate Swaps, previously recorded in AOCI	(0.4)	$ (0.2)	(0.2)
Fair Value Adjustment
Derivatives, Fair Value
Derivative loss (gain), net	(2.3)	0.2	1.6
Reclassification from AOCI \| Interest expense, net
Derivatives, Fair Value
Derivative loss (gain), net	1.0	2.3	1.2
Reclassified from AOCI \| Loss on extinguishment and refinancing of debt
Derivatives, Fair Value
Derivative loss (gain), net	$ 6.1	$ 0.0	$ 0.0

Accumulated Other Comprehensive Income, Cumulative Changes in Net Income (Loss) from Hedges, Before Tax

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- Definition

Derivative Instruments Not Designated as Hedging Instruments, Cash Settlements, Net

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- Definition

Payments on interest rate swaps

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- Definition

Write-off of Interest Rate Swap Loss, previously recorded in AOCI

+ References

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- Definition

Write-off of Tax Benefit related to Interest Rate Swaps, previously recorded in AOCI

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- Definition

Amount, after tax, of accumulated gain (loss) on derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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- Definition

Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled after one year or the normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

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- Definition

Indicates line item in statement of financial position that includes derivative liability.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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