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Derivative Instruments and Hedging Activities - Interest Swap Contracts (Details) - Cash Flow Hedging [Member] $ in Millions | 12 Months Ended
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Sep. 30, 2025 USD ($)
Interest Rate Swap Agreement One [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.018%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Two [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.40%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Three [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.525%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Four [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.535%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Five [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.45%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Six [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.541%
Derivative, mark-to-market gain | $ 0.7
Interest Rate Swap Agreement Seven [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.552%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Eight [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.426%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Nine [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.577%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Ten [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.45%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Eleven [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.35%
Derivative, mark-to-market gain | $ 0.8
Interest Rate Swap Agreement Twelve [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 1 year 6 months
Derivative, notional amount | $ 125.0
Derivative, fixed interest rate | 3.567%
Derivative, mark-to-market gain | $ 0.2
Interest Rate Swap Agreement Thirteen [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 1 year 6 months
Derivative, notional amount | $ 225.0
Derivative, fixed interest rate | 3.567%
Derivative, mark-to-market gain | $ 0.4
Interest Rate Swap Agreement Fourteen [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.58%
Derivative, mark-to-market gain | $ 0.3
Interest Rate Swap Agreement Fifteen [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.611%
Derivative, mark-to-market gain | $ 0.3
Interest Rate Swap Agreement Sixteen [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.657%
Derivative, mark-to-market gain | $ 0.3
Interest Rate Swap Agreement Seventeen [Member] |
Derivative [Line Items] |
Derivative, hedge term (Year) | 10 years
Derivative, notional amount | $ 25.0
Derivative, fixed interest rate | 3.763%
Derivative, mark-to-market gain | $ 0.5
Interest Rate Swap [Member] |
Derivative [Line Items] |
Derivative, notional amount | 725.0
Derivative, mark-to-market gain | $ 10.7

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