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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Property and Equipment to Accounting Pronouncements (Details) - USD ($) $ in Millions	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Property and Equipment
Impairment of property and equipment		$ 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	$ 0.6
Contract Costs
Practical expedient to expense as incurred any incremental costs to obtain and fulfill customer contracts	true
Maximum
Property and Equipment
Impairment of property and equipment	$ 0.1
Land improvements \| Minimum
Property and Equipment
Estimated useful lives	10 years
Land improvements \| Maximum
Property and Equipment
Estimated useful lives	15 years
Warehouse equipment \| Minimum
Property and Equipment
Estimated useful lives	3 years
Warehouse equipment \| Maximum
Property and Equipment
Estimated useful lives	20 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
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	2 years
Vehicles \| Maximum
Property and Equipment
Estimated useful lives	5 years