Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2022	Sep. 30, 2021
Property Plant And Equipment [Line Items]
Property and equipment	$ 792.4	$ 686.7
Less: Accumulated depreciation	469.4	422.3
Property and equipment, net	323.0	264.4
Land
Property Plant And Equipment [Line Items]
Property and equipment	43.3	42.2
Building and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment	45.8	38.6
Operating Equipment
Property Plant And Equipment [Line Items]
Property and equipment	303.1	239.1
Transportation Vehicles
Property Plant And Equipment [Line Items]
Property and equipment	321.2	288.4
Office Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment	74.5	74.3
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment	$ 4.5	$ 4.1
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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