Statements Of Stockholders' Equity (USD $)	Class A voting Common Stock [Member]	Capital in Excess of Par Value [Member]	Deferred Directors' Compensation [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Total
Balances at Sep. 30, 2012	$ 140,524	$ 2,020,229	$ 2,676,160	$ 84,821,395	$ (5,806,162)	$ 83,852,146
Balances, Treasury shares at Sep. 30, 2012					(181,310)
Balances, shares at Sep. 30, 2012	8,431,502
Purchase of treasury stock					(1,214,638)	(1,214,638)
Purchase of treasury stock, shares					(42,206)
Restricted stock awards		541,937				541,937
Net income				8,240,953		8,240,953
Dividends				(1,746,217)		(1,746,217)
Distribution of deferred directors' compensation		(82,547)	(297,154)		394,687	14,986
Distribution of deferred directors' compensation, shares					12,361
Increase in deferred directors' compensation charged to expense			288,759			288,759
Balances at Jun. 30, 2013	140,524	2,479,619	2,667,765	91,316,131	(6,626,113)	89,977,926
Balances, Treasury shares at Jun. 30, 2013					(211,155)
Balances, shares at Jun. 30, 2013	8,431,502
Balances at Sep. 30, 2013	140,524	2,587,838	2,756,526	96,454,449	(6,283,851)	95,655,486
Balances, Treasury shares at Sep. 30, 2013					(200,248)	(200,248)
Balances, shares at Sep. 30, 2013	8,431,502
Purchase of treasury stock					(122,044)	(122,044)
Purchase of treasury stock, shares					(3,722)
Restricted stock awards		499,791				499,791
Net income				15,703,476		15,703,476
Dividends				(1,995,812)		(1,995,812)
Distribution of restricted stock to officers and directors		(320,014)			337,198	17,184
Distribution of restricted stock to officers and directors, shares					11,096
Increase in deferred directors' compensation charged to expense			269,608			269,608
Balances at Jun. 30, 2014	$ 140,524	$ 2,767,615	$ 3,026,134	$ 110,162,113	$ (6,068,697)	$ 110,027,689
Balances, Treasury shares at Jun. 30, 2014					(192,874)	(192,874)
Balances, shares at Jun. 30, 2014	8,431,502