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Commitment and Contingencies - Additional Information (Details) - USD ($) $ in Millions | Jun. 30, 2025 | Sep. 30, 2024
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Commitments And Contingencies [Line Items] |  |
Reserve for unpaid and incurred but not reported claims, amount | $ 181.9 | $ 165.6
Reserve for unpaid and incurred but not reported claims, classified in current liabilities | 57.2 | 52.8
Reserve for unpaid and incurred but not reported claims, classified in non-current liabilities | 124.7 | 112.8
Claims recoverable from third party insurance carriers | 25.5 | 13.4
Other Current Assets |  |
Commitments And Contingencies [Line Items] |  |
Claims recoverable from third party insurance carriers | 7.3 | 4.0
Other Assets |  |
Commitments And Contingencies [Line Items] |  |
Claims recoverable from third party insurance carriers | $ 18.2 | $ 9.4

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- Definition Estimated costs as of the balance sheet date of settling insured claims and costs incurred in the claims settlement process for claims that have not yet been submitted to the insurance company for reimbursement. + References No definition available. + Details
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