Note 3 - Loans/Leases Receivable (Detail) - Aging of the Loan/Lease Portfolio (USD $)	Sep. 30, 2012	Dec. 31, 2011
Current	$ 1,217,321,626	$ 1,168,978,194
30-59 Days Past Due	4,085,420	3,798,637
60-89 Days Past Due	1,935,854	5,257,872
Accruing Past Due 90 Days or More	202,483	1,111,079
Nonacrrual Loans/Loans	17,731,331	18,994,839
Total	1,241,276,714	1,198,140,621
Current as a percentage of total loan/lease portfolio	98.07%	97.57%
30-59 Days Past Due as a percentage of total loan/lease portfolio	0.33%	0.32%
60-89 Days Past Due as a percentage of total loan/lease portfolio	0.16%	0.44%
Accruing Past Due 90 Days or More as a percentage of total loan/lease portfolio	0.02%	0.09%
Nonacrrual Loans/Loans as a percentage of total loan/lease portfolio	1.43%	1.59%
Total as a percentage of total loan/lease portfolio	100.00%	100.00%
Commercial and Industrial [Member]
Current	352,308,795	347,417,683
30-59 Days Past Due	872,105	226,394
60-89 Days Past Due	15,252	239,991
Accruing Past Due 90 Days or More	149,750	120,000
Nonacrrual Loans/Loans	1,657,986	2,790,210
Total	355,003,888	350,794,278
Owner-occupied commercial real estate [Member]
Current	198,070,105	166,632,318
30-59 Days Past Due	0	146,847
60-89 Days Past Due	1,046,835	0
Accruing Past Due 90 Days or More	0	0
Nonacrrual Loans/Loans	671,184	1,011,456
Total	199,788,124	167,790,621
Commercial construction, land development, and other land [Member]
Current	47,080,534	55,741,827
30-59 Days Past Due	0	211,878
60-89 Days Past Due	0	486,802
Accruing Past Due 90 Days or More	0	968,919
Nonacrrual Loans/Loans	2,111,375	2,975,312
Total	49,191,909	60,384,738
Other commercial real estate [Member]
Current	332,708,671	336,080,128
30-59 Days Past Due	2,325,809	522,323
60-89 Days Past Due	733,442	3,732,935
Accruing Past Due 90 Days or More	0	0
Nonacrrual Loans/Loans	10,155,795	9,293,105
Total	345,923,717	349,628,491
Leases receivable [Member]
Current	100,205,091	91,273,406
30-59 Days Past Due	632,458	826,187
60-89 Days Past Due	106,595	396,344
Accruing Past Due 90 Days or More	0	0
Nonacrrual Loans/Loans	1,094,724	716,425
Total	102,038,868	93,212,362
Residential Real Estate [Member]
Current	111,142,654	95,456,433
30-59 Days Past Due	0	1,127,465
60-89 Days Past Due	0	389,678
Accruing Past Due 90 Days or More	0	0
Nonacrrual Loans/Loans	1,349,565	1,133,475
Total	112,492,219	98,107,051
Installment and Other Consumer [Member]
Current	75,805,776	76,376,399
30-59 Days Past Due	255,048	737,543
60-89 Days Past Due	33,730	12,122
Accruing Past Due 90 Days or More	52,733	22,160
Nonacrrual Loans/Loans	690,702	1,074,856
Total	$ 76,837,989	$ 78,223,080