EQUITY METHOD INVESTMENT - Equity investee's summarized financial data (Details) - USD ($)	6 Months Ended	12 Months Ended
Sep. 30, 2020	Sep. 30, 2020
EQUITY METHOD INVESTMENT
Net income (loss) attributable to AMCON, net of tax (1)		$ 183,579
Team Sledd
EQUITY METHOD INVESTMENT
Sales	$ 350,685,407
Gross profit	14,218,204
Net income (loss) before income taxes (1)	551,280
Net income (loss) attributable to AMCON, net of tax (1)	$ 183,579	$ 200,000

The amount of gross profit (loss) reported by an equity method investment of the entity.

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