Taxes (Details) (USD $)	3 Months Ended								12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jun. 30, 2011	Mar. 31, 2011	Dec. 31, 2010	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Summary of reconciliation between GAAP net income and taxable income
Net income (loss) applicable to shareholders	$ 673,342	$ 911,582	$ 7,240,227	$ 4,346,218	$ 1,739,771	$ 3,038,499	$ 2,794,332	$ 3,766,377	$ 13,171,369	$ 11,338,979	$ 8,486,301
Book / tax difference on gains / (losses) from capital transactions									(6,044,065)	(5,166,203)	(1,800,776)
Stock option expense									598,311	163,150	33,860
Deferred compensation									0	54,608	156,832
Other book / tax differences, net									(569,472)	(835,694)	(125,425)
Taxable income before adjustments									7,156,143	5,554,940	6,750,792
Add/(Less) capital gains (losses)									5,100,437	2,908,322	1,175,321
Estimated taxable income subject to 90% dividend requirement									$ 12,256,580	$ 8,463,262	$ 7,926,113