Commitment and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2025	Sep. 30, 2024
Commitments And Contingencies [Line Items]
Reserve for unpaid and incurred but not reported claims, amount	$ 176.7	$ 165.6
Reserve for unpaid and incurred but not reported claims, classified in current liabilities	52.2	52.8
Reserve for unpaid and incurred but not reported claims, classified in non-current liabilities	124.5	112.8
Claims recoverable from third party insurance carriers	18.2	13.4
Other Current Assets
Commitments And Contingencies [Line Items]
Claims recoverable from third party insurance carriers	5.2	4.0
Other Assets
Commitments And Contingencies [Line Items]
Claims recoverable from third party insurance carriers	$ 13.0	$ 9.4