PROPERTY AND EQUIPMENT, NET (Details) - USD ($)	Sep. 30, 2018	Sep. 30, 2017
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	$ 42,396,025	$ 38,749,769
Less accumulated depreciation and amortization: Owned property and equipment	(26,627,541)	(25,441,783)
Property and equipment, net	15,768,484	13,307,986
Land
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	773,068	648,818
Buildings and improvements
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	12,206,908	10,661,543
Warehouse equipment
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	13,424,236	13,195,827
Furniture, fixtures and leasehold improvements
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	12,018,984	10,732,163
Vehicles
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	3,229,551	2,195,704
Construction in progress
PROPERTY AND EQUIPMENT, NET
Property and equipment, gross	$ 743,278	$ 1,315,714