Consolidated Statements of Changes in Stockholders' Equity - USD ($)	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2012	$ 54,867	$ 5,039,448	$ 78,912,791	$ 53,326,542	$ 4,706,683	$ (1,606,510)	$ 140,433,821
Net income				14,938,245			14,938,245
Other comprehensive loss, net of tax					(18,350,669)		(18,350,669)
Common cash dividends declared, $0.08 per share				(459,312)			(459,312)
Preferred cash dividends declared and accrued				(3,168,302)			(3,168,302)
Issuance of 834,715 shares of common stock as a result of the acquisition of Community National Bancorporation, net		834,715	12,181,894				13,016,609
Conversion of 25,000 shares of Series E Non-cumulative Perpetual Preferred Stock to 2,057,502 shares of common stock	(25,000)	2,057,502	(2,032,502)
Proceeds from issuance of common stock, Employee Stock Purchase Plan		27,110	304,396				331,506
Proceeds from issuance of common stock, stock options exercised		41,258	373,519				414,777
Exchange of 7,679 shares of common stock in connection with stock options exercised		(7,679)	(120,955)				(128,634)
Stock-based compensation expense			792,279				792,279
Tax benefit of nonqualified stock options exercised			62,371				62,371
Restricted stock awards		30,152	(30,152)
Exchange of common stock, restricted stock vested		(16,798)	(289,113)				(305,911)
Balance at Dec. 31, 2013	29,867	8,005,708	90,154,528	64,637,173	(13,643,986)	(1,606,510)	147,576,780
Net income				14,952,537			14,952,537
Other comprehensive loss, net of tax					11,708,770		11,708,770
Common cash dividends declared, $0.08 per share				(631,009)			(631,009)
Preferred cash dividends declared and accrued				(1,081,877)			(1,081,877)
Redemption of 29,867 shares of Series F Non-cumulative Perpetual Preferred Stock	$ (29,867)		(29,794,055)				(29,823,922)
Proceeds from issuance of common stock, Employee Stock Purchase Plan		25,321	353,566				378,887
Proceeds from issuance of common stock, stock options exercised		23,659	218,095				241,754
Stock-based compensation expense			891,619				891,619
Tax benefit of nonqualified stock options exercised			42,954				42,954
Restricted stock awards		30,055	(30,055)
Exchange of common stock, restricted stock vested		(10,300)	(167,684)				(177,984)
Balance at Dec. 31, 2014		8,074,443	61,668,968	77,876,824	(1,935,216)	(1,606,510)	144,078,509
Net income				16,927,881			16,927,881
Other comprehensive loss, net of tax					(188,613)		(188,613)
Common cash dividends declared, $0.08 per share				(934,682)			(934,682)
Proceeds from issuance of 3,680,000 share of common stock, net of issuance costs		3,680,000	59,804,123				63,484,123
Proceeds from issuance of common stock, Employee Stock Purchase Plan		24,033	375,120				399,153
Proceeds from issuance of common stock, stock options exercised		78,909	1,074,611				1,153,520
Stock-based compensation expense			941,469				941,469
Tax benefit of nonqualified stock options exercised			93,096				93,096
Retirement of treasury stock, 121,246 shares of common stock		(121,246)	(580,886)	(904,378)		$ 1,606,510
Restricted stock awards		28,846	(28,846)
Exchange of common stock, restricted stock vested		(3,902)	(64,804)				(68,706)
Balance at Dec. 31, 2015		$ 11,761,083	$ 123,282,851	$ 92,965,645	$ (2,123,829)		$ 225,885,750