Commitment and Contingencies - Additional Information (Details) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Commitments And Contingencies [Line Items]
Reserve for unpaid and incurred but not reported claims, amount	$ 145.9	$ 146.7
Reserve for unpaid and incurred but not reported claims, classified in current liabilities	50.5	45.6
Reserve for unpaid and incurred but not reported claims, classified in non-current liabilities	95.4	101.1
Claims recoverable from third party insurance carriers	11.6	17.9
Other Current Assets
Commitments And Contingencies [Line Items]
Claims recoverable from third party insurance carriers	3.4	5.1
Other Assets
Commitments And Contingencies [Line Items]
Claims recoverable from third party insurance carriers	$ 8.2	$ 12.8