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Commitments and Contingencies (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Loss Contingencies [Line Items]
Loss Contingency, Discounted Amount of Insurance-related Assessment Liability	$ 12,131	$ 11,158
Letters of Credit Outstanding, Amount	$ 5,545
Unrecorded Unconditional Purchase Obligation, Term	12 months
Estimated cost of completion of bonded projects	$ 199,767
Insurance Related [Member]
Loss Contingencies [Line Items]
Letters of Credit Outstanding, Amount	$ 5,545	$ 4,756

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Estimated cost of completion of bonded projects

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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The present value of the liability as of the balance sheet date representing required funding mandated by statute or regulatory authority that is related directly or indirectly to underwriting activities, including pools for self-insurance and excluding premium taxes and income taxes. The funds derived from the assessments generally enable a government guarantor to pay insurance claims in the event that the underwriting insurer is insolvent or otherwise unable to meet its payment obligations.

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Term of the unrecognized unconditional purchase obligation, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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