Consolidated Statements of Changes in Stockholders' Equity - USD ($)	Total	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]
Beginning Balance, Shares at Dec. 31, 2013		10,286,363
Beginning Balance at Jun. 30, 2014	$ 102,830,362	$ 51,623,790	$ 7,675,072	$ 43,565,948	$ (159,186)	$ 124,738
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	5,858,244			5,720,839		137,405
Other comprehensive income (loss)	260,310				260,310
Stock-based compensation expense, net of forfeitures and income taxes (shares)		(1,200)
Stock-based compensation expense, net of forfeitures and income taxes	419,049	$ (6,000)	425,049
Stock options exercised, shares		25,456
Stock options exercised, including income tax benefit	215,732	$ 127,280	88,452
Cash dividend declared on common stock ($0.15 and $0.17 per share during the six months ended June 30, 2014 and 2015, respectively)	(1,592,010)			(1,592,010)
Common stock issued through dividend reinvestment, shares		14,139
Common stock issued through dividend reinvestment	163,539	$ 70,695	92,844
Cash in lieu of fractional shares	12		12
Distributions to non-controlling interests	(240,211)					(240,211)
Ending Balance, Shares at Jun. 30, 2014		10,324,758
Ending Balance at Dec. 31, 2013	97,745,598	$ 51,431,815	7,068,715	39,437,119	(419,496)	227,445
Beginning Balance, Shares at Dec. 31, 2014		10,372,725
Beginning Balance at Jun. 30, 2015	113,459,217	$ 52,182,575	8,845,632	52,411,915	(65,407)	84,502
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income	6,968,183			6,885,036		83,147
Other comprehensive income (loss)	36,830				36,830
Stock-based compensation expense, net of forfeitures and income taxes (shares)		0
Stock-based compensation expense, net of forfeitures and income taxes	343,922	$ 0	343,922
Stock options exercised, shares		63,790
Stock options exercised, including income tax benefit	485,122	$ 318,950	166,172
Cash dividend declared on common stock ($0.15 and $0.17 per share during the six months ended June 30, 2014 and 2015, respectively)	(1,827,528)			(1,827,528)
Contributions from non-controlling interests	99					99
Distributions to non-controlling interests	(84,629)					(84,629)
Ending Balance, Shares at Jun. 30, 2015		10,436,515
Ending Balance at Dec. 31, 2014	$ 107,537,317	$ 51,863,625	$ 8,335,538	$ 47,354,407	$ (102,237)	$ 85,984