Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2022	Sep. 30, 2022
Property Plant And Equipment [Line Items]
Property and equipment	$ 842.1	$ 812.6
Less: Accumulated depreciation	502.9	484.3
Property and equipment, net	339.2	328.3
Land
Property Plant And Equipment [Line Items]
Property and equipment	43.3	43.3
Building and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment	47.3	46.3
Operating Equipment
Property Plant And Equipment [Line Items]
Property and equipment	325.1	302.4
Transportation Vehicles
Property Plant And Equipment [Line Items]
Property and equipment	344.5	339.8
Office Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment	75.6	75.1
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment	$ 6.3	$ 5.7
Minimum \| Building and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	2 years
Minimum \| Operating Equipment
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	2 years
Minimum \| Transportation Vehicles
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	3 years
Minimum \| Office Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	3 years
Maximum \| Building and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	40 years
Maximum \| Operating Equipment
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	7 years
Maximum \| Transportation Vehicles
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	7 years
Maximum \| Office Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, Useful Life	10 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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