Consolidated Statement of Changes in Stockholders' Equity (Unaudite) (USD $)	Preferred Stock [Member]	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Noncontrolling Interest [Member]	Treasury Stock [Member]	Total
Balance at Dec. 31, 2010	$ 63,237	$ 4,732,428	$ 86,478,269	$ 40,550,900	$ 704,165	$ 1,648,219	$ (1,606,510)	$ 132,570,708
Comprehensive income:
Net income				2,124,960		106,524		2,231,484
Other comprehensive income (loss), net of tax					(1,345,554)			(1,345,554)
Comprehensive income								885,930
Discount accretion on cumulative preferred stock			116,909	(116,909)
Proceeds from issuance of common stock as a result of stock purchased under the Employee Stock Purchase Plan		9,081	49,249					58,330
Proceeds from issuance of common stock as a result of stock options exercised		24,300	146,067					170,367
Exchange of common stock		(2,171)	(14,070)					(16,241)
Stock compensation expense			206,569					206,569
Restricted stock awards		69,924	(69,924)
Distributions to noncontrolling interests						(2,065)		(2,065)
Balance at Mar. 31, 2011	63,237	4,833,562	86,913,069	41,643,489	(641,389)	1,752,678	(1,606,510)	132,958,136
Comprehensive income:
Net income				2,674,969		98,245		2,773,214
Other comprehensive income (loss), net of tax					2,409,728			2,409,728
Comprehensive income								5,182,942
Common cash dividends declared				(185,863)				(185,863)
Preferred cash dividends declared and accrued				(915,462)				(915,462)
Discount accretion on cumulative preferred stock			120,280	(120,280)
Proceeds from issuance of common stock as a result of stock purchased under the Employee Stock Purchase Plan		11,355	61,582					72,937
Proceeds from issuance of common stock as a result of stock options exercised		10,967	65,205					76,172
Exchange of common stock		(379)	(3,033)					(3,412)
Stock compensation expense			141,370					141,370
Distributions to noncontrolling interests						(2,066)		(2,066)
Balance at Jun. 30, 2011	63,237	4,855,505	87,298,473	43,096,853	1,768,339	1,848,857	(1,606,510)	137,324,754
Balance at Dec. 31, 2011	65,090	4,879,435	89,702,533	44,585,902	4,754,714	2,051,538	(1,606,510)	144,432,702
Comprehensive income:
Net income				3,236,818		166,031		3,402,849
Other comprehensive income (loss), net of tax					(1,517,235)			(1,517,235)
Comprehensive income								1,885,614
Preferred cash dividends declared and accrued				(938,625)				(938,625)
Proceeds from issuance of common stock as a result of stock purchased under the Employee Stock Purchase Plan		7,767	55,566					63,333
Proceeds from issuance of common stock as a result of stock options exercised		276	2,374					2,650
Exchange of common stock		(576)	(2,103)					(2,679)
Stock compensation expense			326,245					326,245
Restricted stock awards		57,770	(57,770)
Distributions to noncontrolling interests						(2,066)		(2,066)
Balance at Mar. 31, 2012	65,090	4,944,672	90,026,845	46,884,095	3,237,479	2,215,503	(1,606,510)	145,767,174
Balance at Dec. 31, 2011	65,090						(1,606,510)	144,432,702
Comprehensive income:
Net income								6,676,228
Other comprehensive income (loss), net of tax								(276,190)
Comprehensive income								6,400,038
Redemption of 10,223 shares of Series F Noncumulative Perpetual Preferred Stock	(10,223)							(10,223,000)
Balance at Jun. 30, 2012	54,867						(1,606,510)	139,322,092
Balance at Jan. 30, 2012
Comprehensive income:
Redemption of 10,223 shares of Series F Noncumulative Perpetual Preferred Stock	(10,223)							(10,223,000)
Distributions to noncontrolling interests						(2,065)		(2,065)
Balance at Jun. 30, 2012	54,867					2,414,661	(1,606,510)	139,322,092
Balance at Mar. 31, 2012	65,090	4,944,672	90,026,845	46,884,095	3,237,479	2,215,503	(1,606,510)	145,767,174
Comprehensive income:
Net income				3,072,156		201,223		3,273,379
Other comprehensive income (loss), net of tax					1,241,045			1,241,045
Comprehensive income								4,514,424
Common cash dividends declared				(189,091)				(189,091)
Preferred cash dividends declared and accrued				(935,786)				(935,786)
Redemption of 10,223 shares of Series F Noncumulative Perpetual Preferred Stock	(10,223)		(10,212,777)					(10,223,000)
Proceeds from issuance of common stock as a result of stock purchased under the Employee Stock Purchase Plan		10,856	78,055					88,911
Proceeds from issuance of common stock as a result of stock options exercised		9,090	79,902					88,992
Exchange of 611 shares of common stock in connection with stock options exercised		(611)	(7,125)					(7,736)
Proceeds from exercise of warrants to purchase 4,300 shares of common stock issued in conjunction with the Series A Subordinated Notes		4,300	38,700					43,000
Stock compensation expense			177,269					177,269
Balance at Jun. 30, 2012	$ 54,867	$ 4,968,307	$ 80,180,869	$ 48,831,374	$ 4,478,524	$ 2,414,661	$ (1,606,510)	$ 139,322,092