Condensed Consolidated Unaudited Statements of Cash Flows - USD ($)	6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 2,768,536	$ 1,818,990
Adjustments to reconcile net income from operations to net cash flows from operating activities:
Depreciation	1,217,986	1,020,783
Amortization	31,250	48,125
Gain on sale of property and equipment	(17,832)	(300)
Equity-based compensation	622,390	642,785
Deferred income taxes	226,918	(423,322)
Provision (recovery) for losses on doubtful accounts	59,000	(77,000)
Inventory allowance	240,699	(231,625)
Other	1,978	1,978
Changes in assets and liabilities:
Accounts receivable	3,353,602	1,521,705
Inventories	20,978,357	(2,951,171)
Prepaid and other current assets	(2,402,722)	1,216,336
Other assets	7,897	(19,903)
Accounts payable	(467,687)	126,012
Accrued expenses and accrued wages, salaries and bonuses	(2,275,795)	(1,059,839)
Income taxes payable / receivable	273,742	(368,469)
Net cash flows from operating activities	24,618,319	1,265,085
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of property and equipment	(2,159,232)	(1,366,767)
Proceeds from sales of property and equipment	23,700	300
Net cash flows used in investing activities	(2,135,532)	(1,366,467)
CASH FLOWS FROM FINANCING ACTIVITIES:
Borrowings under revolving credit facility	642,850,736	623,945,799
Repayments under revolving credit facility	(661,055,136)	(622,433,675)
Principal payments on long-term debt	(556,969)	(185,753)
Repurchase of common stock	(3,186,846)	(644,528)
Dividends on common stock	(413,100)	(458,859)
Withholdings on the exercise of equity-based awards		(79,850)
Net cash flows from (used in) financing activities	(22,361,315)	143,134
Net change in cash	121,472	41,752
Cash, beginning of period	520,644	523,065
Cash, end of period	642,116	564,817
Supplemental disclosure of cash flow information:
Cash paid during the period for interest	774,784	489,840
Cash paid during the period for income taxes	674,340	705,790
Supplemental disclosure of non-cash information:
Equipment acquisitions classified in accounts payable	212,800	63,962
Issuance of common stock in connection with the vesting and exercise of equity-based awards	$ 1,005,792	$ 1,183,091