Consolidated Statements of Cash Flows (USD $)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Cash Flows from Operating Activities:
Net income	$ 10,129,869	$ 6,807,726	$ 2,048,831
Adjustments to reconcile net income to net cash provided by operating activities
Depreciation	2,442,896	2,533,597	2,780,190
Provision for loan/lease losses	6,616,014	7,463,618	16,975,517
Deferred income taxes	1,228,529	1,256,004	2,758,856
Amortization of offering costs on subordinated debentures	14,317	14,317	14,317
Stock-based compensation expense	696,407	488,112	512,963
Losses (gains) on sales of other real estate owned, net	374,910	835,163	(177,736)
Amortization of premiums on securities, net	3,487,361	3,411,202	2,044,767
Securities gains, net	(1,472,528)		(1,488,391)
Other-than-temporary impairment losses on securities	118,847	113,800	206,369
Loans originated for sale	(100,789,010)	(172,623,744)	(140,376,155)
Proceeds on sales of loans	113,606,152	167,843,529	143,295,985
Gains on sales of loans, net	(2,565,043)	(3,169,514)	(1,677,312)
Prepayment fees on Federal Home Loan Bank advances	832,099
Losses on lease residual values		617,000
Decrease (increase) in accrued interest receivable	(74,032)	1,129,524	270,322
Decrease (increase) in prepaid FDIC insurance	1,677,908	2,439,762	(7,801,076)
Increase in cash value of bank-owned life insurance	(1,445,891)	(1,331,085)	(1,243,324)
Increase in other assets	(761,916)	(1,320,430)	(3,339,319)
Increase (decrease) in other liabilities	2,523,387	1,406,270	(660,397)
Net cash provided by operating activities	36,640,276	17,914,851	14,144,407
Cash Flows from Investing Activities:
Net decrease (increase) in federal funds sold	41,175,000	(55,361,667)	14,097,565
Net decrease (increase) in interest-bearing deposits at financial institutions	12,995,009	(10,416,198)	(27,215,509)
Proceeds from sales of other real estate owned	9,220,631	6,038,825	1,358,351
Activity in securities portfolio:
Purchases	(622,245,920)	(383,018,764)	(316,260,882)
Calls, maturities and redemptions	422,870,000	325,649,238	169,176,856
Paydowns	9,094,080	435,149	406,998
Sales	54,326,191		25,966,885
Activity in restricted investment securities:
Purchases	(292,800)	(1,710,800)	(1,150,500)
Redemptions	1,707,900	252,200
Activity in bank-owned life insurance:
Purchases	(7,000,000)	(3,150,000)	(1,000,002)
Surrender of policy		609,772
Net (increase) decrease in loans/leases originated and held for investment	(56,096,989)	63,387,668	(50,077,380)
Purchase of premises and equipment	(3,064,903)	(2,197,448)	(2,845,816)
Net cash used in investing activities	(137,311,801)	(59,482,025)	(187,543,434)
Cash Flows from Financing Activities:
Net increase in deposits	90,641,931	25,493,131	30,364,128
Net increase (decrease) in short-term borrowings	72,381,951	(9,745,072)	49,442,621
Activity in Federal Home Loan Bank advances:
Advances	5,000,000	36,000,000	11,500,000
Calls and maturities	(24,000,000)	(13,100,000)	(14,345,000)
Prepayments	(15,832,099)
Net (decrease) increase in other borrowings	(13,839,122)	7,395,184	64,477,207
Proceeds from issuance of Series A Subordinated Notes and detachable warrants to purchase 54,000 shares of common stock		2,700,000
Payment of cash dividends on common and preferred stock	(3,712,493)	(4,052,089)	(3,595,221)
Proceeds from issuance of Series F Noncumulative Perpetual Preferred Stock, net	39,996,922
Redemption of Series D Cumulative Perpetual Preferred Stock, net	(38,237,000)
Repurchase of 521,888 shares of common stock warrants issued in conjunction with Series D Cumulative Perpetual Preferred Stock	(1,100,000)
Proceeds from issuance of Series E Noncumulative Convertible Perpetual Preferred Stock, net		3,187,233
Proceeds from issuance of Series D Cumulative Perpetual Preferred Stock and common stock warrant, net			38,052,823
Proceeds from issuance of common stock, net	477,339	261,547	226,441
Purchase of noncontrolling interests		(420,000)	(310,000)
Net cash provided by financing activities	111,777,429	47,719,934	175,812,999
Net increase in cash and due from banks	11,105,904	6,152,760	2,413,972
Cash and due from banks, beginning	42,030,806	35,878,046	33,464,074
Cash and due from banks, ending	53,136,710	42,030,806	35,878,046
Supplemental Disclosures of Cash Flow Information, cash payments for:
Interest	24,194,198	31,017,369	36,536,869
Income and franchise taxes	1,246,489	3,236,558	2,557,505
Change in accumulated other comprehensive income (loss), unrealized gains (losses) on securities available for sale, net	4,050,549	568,557	(3,492,752)
Exchange of shares of common stock in connection with payroll taxes for restricted stock and options exercised		(3,097)	(7,719)
Transfers of loans to other real estate owned	$ 9,446,588	$ 6,122,328	$ 6,924,975