Deferred Compensation Plan For Directors (Details) - USD ($)	12 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Deferred Compensation Plan For Directors [Line Items]
Number of shares credited to directors deferred fee account	261,846	272,564
Outstanding deferred balance	$ 3,459,909	$ 3,403,213
Total expenses charged to the company's results of operations	$ 358,658	$ 329,465	$ 302,353
Maximum [Member]
Deferred Compensation Plan For Directors [Line Items]
Period outside directors may elect to receive shares	10 years