Property and Equipment, Net - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Property Plant And Equipment [Line Items]
Property and equipment	$ 1,153.2	$ 1,092.5
Less: Accumulated depreciation	591.6	550.9
Property and equipment, net	561.6	541.6
Land
Property Plant And Equipment [Line Items]
Property and equipment	42.9	42.9
Buildings and Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment	49.4	48.5
Operating Equipment
Property Plant And Equipment [Line Items]
Property and equipment	459.0	443.3
Transportation Vehicles
Property Plant And Equipment [Line Items]
Property and equipment	540.2	491.9
Office Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment	57.4	56.3
Construction in Progress
Property Plant And Equipment [Line Items]
Property and equipment	$ 4.3	$ 9.6
Minimum \| Buildings 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 \| Buildings 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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