Document and Entity Information	6 Months Ended
	Mar. 31, 2013	May 10, 2013 Common stock	May 10, 2013 Class B stock
Entity Registrant Name	GENCOR INDUSTRIES INC
Entity Central Index Key	0000064472
Document Type	10-Q
Document Period End Date	Mar. 31, 2013
Amendment Flag	false
Document Fiscal Year Focus	2013
Document Fiscal Period Focus	Q2
Current Fiscal Year End Date	--09-30
Entity Filer Category	Smaller Reporting Company
Entity Common Stock, Shares Outstanding		8,008,632	1,509,238