Document and Entity Information - shares	9 Months Ended
	Jun. 30, 2018	Jul. 16, 2018
Document and Entity Information
Entity Registrant Name	AMCON DISTRIBUTING CO
Entity Central Index Key	0000928465
Document Type	10-Q
Document Period End Date	Jun. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--09-30
Entity Current Reporting Status	Yes
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		615,988
Document Fiscal Year Focus	2018
Document Fiscal Period Focus	Q3