Fair values as of the balance sheet date of the net amount of all assets and liabilities resulting from contracts that meet the criteria of being accounted for as derivative instruments.

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Amount of gain (loss) from excluded component of derivative hedge, recognized in earnings. Excludes recognition under systematic and rational method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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Derivative Financial Instruments and Fair Value Measurements - Fair Value Measurements (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Interest Rate Swap and Interest Rate Cap \| Other current assets
Derivative financial instruments
Fair values of the interest rate swap and cap agreements	$ 17.2
Interest Rate Swap and Interest Rate Cap \| Other non-current assets
Derivative financial instruments
Fair values of the interest rate swap and cap agreements	37.5
Interest Rate Swap \| Other current assets
Derivative financial instruments
Fair values of the interest rate swap and cap agreements		$ 9.4
Interest Rate Swap \| Other non-current assets
Derivative financial instruments
Fair values of the interest rate swap and cap agreements		$ 41.8
Designated as Hedging Instrument \| Cash Flow Hedging \| Interest Rate Swap
Derivative financial instruments
Losses recognized in income	$ 0.0