Amount of gain (loss) from the increase (decrease) in fair value of derivative and nonderivative instruments designated as fair value hedging instruments recognized in the income statement.

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The percentage points added to the reference rate to compute the variable rate on the interest rate derivative.

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

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Fixed interest rate related to the interest rate derivative.

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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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Nominal or face amount used to calculate payment on derivative.

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Derivative Financial Instruments and Fair Value Measurements - Narrative (Details) - USD ($) $ in Millions	9 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Sep. 30, 2024	Jun. 30, 2022
Derivative [Line Items]
Loss recorded representing decrease in fair value	$ 6.9	$ 1.6
Interest Rate Swap \| Cash Flow Hedging
Derivative [Line Items]
Derivative, basis spread on variable rate (as percent)				3.465%
Interest Rate Swap \| Cash Flow Hedging \| Designated as Hedging Instrument
Derivative [Line Items]
Material losses recognized in income	0.0	$ 0.0
Interest Rate Cap \| Cash Flow Hedging
Derivative [Line Items]
Notional value				$ 300.0
Interest Rate Cap \| Cash Flow Hedging \| Maximum
Derivative [Line Items]
Fixed interest rate (as percent)				3.465%
February 2023 \| United States of America, Dollars \| Interest Rate Swap \| Cash Flow Hedging \| Designated as Hedging Instrument
Derivative [Line Items]
Notional value	$ 400.0		$ 400.0
Fixed interest rate (as percent)	1.283%		1.283%