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					(507,345)	(507,345)
Purchase of treasury stock, shares					(18,056)
Restricted stock awards		399,907				399,907
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			201,211			201,211
Dividends				(1,164,178)		(1,164,178)
Net income				3,170,785		3,170,785
Balances at Mar. 31, 2013	140,524	2,337,589	2,580,217	86,828,002	(5,918,820)	85,967,512
Balances, Treasury shares at Mar. 31, 2013					(187,005)
Balances, shares at Mar. 31, 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		262,174				262,174
Distribution of deferred directors' compensation		(259,511)			275,662	16,151
Distribution of deferred directors' compensation, shares					9,140
Increase in deferred directors' compensation charged to expense			189,506			189,506
Dividends				(1,330,215)		(1,330,215)
Net income				10,580,891		10,580,891
Balances at Mar. 31, 2014	$ 140,524	$ 2,590,501	$ 2,946,032	$ 105,705,125	$ (6,130,233)	$ 105,251,949
Balances, Treasury shares at Mar. 31, 2014					(194,830)	(194,830)
Balances, shares at Mar. 31, 2014	8,431,502