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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment to Accounting Pronouncements (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Sep. 30, 2025 | Sep. 30, 2024
Property and Equipment |  |
Impairment of property and equipment | $ 0.0 | $ 0.0
Revenue Recognition |  |
Practical expedient, financing components | true |
Insurance |  |
Letter of credit issued for worker's compensation insurance carrier as part of the entity's self-insured loss control program | $ 3.1 | 2.4
Contract Costs |  |
Practical expedient to expense as incurred any incremental costs to obtain and fulfill customer contracts | true |
Facilities |  |
Insurance |  |
Line Of Credit Facility Financial Covenant Excess Capacity Availability Fall | $ 3.1 | $ 2.4
Land improvements | Minimum |  |
Property and Equipment |  |
Estimated useful lives | 9 years |
Land improvements | Maximum |  |
Property and Equipment |  |
Estimated useful lives | 15 years |
Buildings and improvements | Minimum |  |
Property and Equipment |  |
Estimated useful lives | 5 years |
Buildings and improvements | Maximum |  |
Property and Equipment |  |
Estimated useful lives | 40 years |
Warehouse equipment | Minimum |  |
Property and Equipment |  |
Estimated useful lives | 2 years |
Warehouse equipment | Maximum |  |
Property and Equipment |  |
Estimated useful lives | 20 years |
Furniture, fixtures and leasehold improvements | Minimum |  |
Property and Equipment |  |
Estimated useful lives | 1 year |
Furniture, fixtures and leasehold improvements | Maximum |  |
Property and Equipment |  |
Estimated useful lives | 12 years |
Vehicles | Minimum |  |
Property and Equipment |  |
Estimated useful lives | 1 year |
Vehicles | Maximum |  |
Property and Equipment |  |
Estimated useful lives | 10 years |

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