Note 3 - Loans/Leases Receivable (Detail) - Allowance for Estimated Losses on Loans/Leases (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
Balance, beginning	$ 19,925,204	$ 18,789,262
Balance, ending	20,769,462	19,006,644
Loans/leases individually evaluated for impairment	18,345,662		24,294,211
Loans/leases collectively evaluated for impairment	1,269,906,622		1,259,917,023
Loans/Leases receivable	1,288,252,284		1,284,211,234
Allowance as a percentage of loans/leases individually evaluated for impairment	24.77%		18.88%
Allowance as a percentage of loans/leases collectively evaluated for impairment	1.28%		1.22%
Allowance as a percentage of loans/leases	1.61%		1.55%
Allowance for loans/leases individually evaluated for impairment	4,543,756		4,587,769
Allowance for loans/leases collectively evaluated for impairment	16,225,706		15,337,435
Provisions charged to expense	1,057,782	780,446
Loans/leases charged off	(302,767)	(824,752)
Recoveries on loans/leases previously charged off	89,243	261,688
Commercial and Industrial [Member]
Balance, beginning	4,531,545	4,878,006
Balance, ending	4,466,264	4,585,467
Loans/leases individually evaluated for impairment	614,021		1,006,952
Loans/leases collectively evaluated for impairment	397,508,219		393,237,300
Loans/Leases receivable	398,122,240		394,244,252
Allowance as a percentage of loans/leases individually evaluated for impairment	81.15%		27.82%
Allowance as a percentage of loans/leases collectively evaluated for impairment	1.00%		1.08%
Allowance as a percentage of loans/leases	1.12%		1.15%
Allowance for loans/leases individually evaluated for impairment	498,260		280,170
Allowance for loans/leases collectively evaluated for impairment	3,968,004		4,251,375
Provisions charged to expense	(87,807)	(90,900)
Loans/leases charged off	(215)	(376,408)
Recoveries on loans/leases previously charged off	22,741	174,769
Commercial Real Estate Loans [Member]
Balance, beginning	11,069,502	10,596,958
Balance, ending	12,188,953	10,855,442
Loans/leases individually evaluated for impairment	14,460,687		20,383,846
Loans/leases collectively evaluated for impairment	584,172,931		573,595,393
Loans/Leases receivable	598,633,618		593,979,239
Allowance as a percentage of loans/leases individually evaluated for impairment	24.26%		19.65%
Allowance as a percentage of loans/leases collectively evaluated for impairment	1.49%		1.23%
Allowance as a percentage of loans/leases	2.04%		1.86%
Allowance for loans/leases individually evaluated for impairment	3,507,839		4,005,042
Allowance for loans/leases collectively evaluated for impairment	8,681,114		7,064,460
Provisions charged to expense	1,114,294	257,864
Recoveries on loans/leases previously charged off	5,157	620
Leases receivable [Member]
Balance, beginning	1,990,395	1,339,496
Balance, ending	2,296,523	1,366,528
Loans/leases individually evaluated for impairment	1,210,936		998,802
Loans/leases collectively evaluated for impairment	108,443,378		102,686,854
Loans/Leases receivable	109,654,314		103,685,656
Allowance as a percentage of loans/leases individually evaluated for impairment	26.86%		12.51%
Allowance as a percentage of loans/leases collectively evaluated for impairment	1.82%		1.82%
Allowance as a percentage of loans/leases	2.09%		1.92%
Allowance for loans/leases individually evaluated for impairment	325,294		125,000
Allowance for loans/leases collectively evaluated for impairment	1,971,229		1,865,395
Provisions charged to expense	378,623	315,446
Loans/leases charged off	(73,049)	(315,721)
Recoveries on loans/leases previously charged off	554	27,307
Residential Real Estate [Member]
Balance, beginning	1,070,328	704,946
Balance, ending	966,336	963,157
Loans/leases individually evaluated for impairment	935,936		1,217,256
Loans/leases collectively evaluated for impairment	114,612,273		114,364,317
Loans/Leases receivable	115,548,209		115,581,573
Allowance as a percentage of loans/leases individually evaluated for impairment	10.18%		8.67%
Allowance as a percentage of loans/leases collectively evaluated for impairment	0.76%		0.84%
Allowance as a percentage of loans/leases	0.84%		0.93%
Allowance for loans/leases individually evaluated for impairment	95,232		105,565
Allowance for loans/leases collectively evaluated for impairment	871,104		964,763
Provisions charged to expense	8,899	262,968
Loans/leases charged off	(112,891)	(4,757)
Installment and Other Consumer [Member]
Balance, beginning	1,263,434	1,269,856
Balance, ending	851,386	1,236,050
Loans/leases individually evaluated for impairment	1,124,082		687,355
Loans/leases collectively evaluated for impairment	65,169,821		76,033,159
Loans/Leases receivable	66,293,903		76,720,514
Allowance as a percentage of loans/leases individually evaluated for impairment	10.42%		10.47%
Allowance as a percentage of loans/leases collectively evaluated for impairment	1.13%		1.57%
Allowance as a percentage of loans/leases	1.28%		1.65%
Allowance for loans/leases individually evaluated for impairment	117,131		71,992
Allowance for loans/leases collectively evaluated for impairment	734,255		1,191,442
Provisions charged to expense	(356,227)	35,068
Loans/leases charged off	(116,612)	(127,866)
Recoveries on loans/leases previously charged off	$ 60,791	$ 58,992