Quarterly Results Of Operations (Details) (USD $)	3 Months Ended								12 Months Ended
	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2012
Quarterly Results Of Operations [Abstract]
Revenues	$ 27,887,446	$ 18,374,977	$ 19,752,045	$ 18,396,756	$ 18,396,254	$ 17,730,445	$ 12,581,986	$ 14,180,435	$ 84,411,224	$ 62,889,120	$ 48,532,317
Income (loss) before provision for income taxes	13,583,986	7,627,585	8,445,573	7,164,318	8,780,096	7,323,168	1,761,487	2,825,298	36,821,462	20,690,049	10,644,996
Net income (loss)	$ 9,297,986	$ 5,122,585	$ 5,654,573	$ 4,926,318	$ 5,719,096	$ 5,070,168	$ 1,022,487	$ 2,148,298	$ 25,001,462	$ 13,960,049	$ 7,370,996
Earnings (loss) per share	$ 0.55	$ 0.31	$ 0.34	$ 0.29	$ 0.34	$ 0.31	$ 0.06	$ 0.13	$ 1.49	$ 0.84	$ 0.44