Note 3 - Loans Leases Receivable - Composition of the Loan Lease Portfolio (Details) - USD ($)		Mar. 31, 2017		Dec. 31, 2016		Mar. 31, 2016	Dec. 31, 2015
Loans		$ 2,427,885,239		$ 2,397,414,282
Plus deferred loan/lease origination costs, net of fees		7,965,176		8,072,703
Gross loans/leases receivable		2,435,850,415		2,405,486,985
Less allowance		(32,059,150)		(30,757,448)		$ (27,395,442)	$ (26,140,906)
		2,403,791,265		2,374,729,537
Commercial Portfolio Segment [Member]
Loans		851,578,347		827,637,263
Less allowance		(12,954,090)		(12,545,110)		(10,991,979)	(10,484,080)
Commercial Real Estate Portfolio Segment [Member]
Loans		1,106,841,721		1,093,458,860
Less allowance		(12,643,266)		(11,670,609)		(10,090,567)	(9,375,117)
Commercial Real Estate Portfolio Segment [Member] | Owner Occupied Commercial Real Estate Loans [Member]
Loans		316,902,218		332,387,621
Commercial Real Estate Portfolio Segment [Member] | Construction Loans [Member]
Loans		171,901,708		165,149,491
Commercial Real Estate Portfolio Segment [Member] | Other Non-owner Occupied Commercial Real Estate Loans [Member]
Loans		618,037,795		595,921,748
Finance Leases Portfolio Segment [Member]
Loans	[1],[2]	159,368,425		165,419,360
Plus deferred loan/lease origination costs, net of fees	[1]	5,730,479		5,881,778
Gross loans/leases receivable	[1]	165,098,904		171,301,138
Less allowance		(2,978,260)	[1]	(3,111,898)	[1]	(3,287,231)	(3,395,088)
	[1]	162,120,644		168,189,240
Net minimum lease payments to be received	[1]	177,088,295		184,274,802
Estimated unguaranteed residual values of leased assets	[1]	1,085,154		1,085,154
Unearned lease/residual income	[1]	(18,805,024)		(19,940,596)
Residential Portfolio Segment [Member]
Loans	[2],[3]	231,325,899		229,233,104
Less allowance		(2,375,864)		(2,342,344)		(1,836,622)	(1,790,150)
Consumer Portfolio Segment [Member]
Loans	[2]	78,770,847		81,665,695
Less allowance		$ (1,107,670)		$ (1,087,487)		$ (1,189,043)	$ (1,096,471)

[1] Management performs an evaluation of the estimated unguaranteed residual values of leased assets on an annual basis, at a minimum. The evaluation consists of discussions with reputable and current vendors, which is combined with management's expertise and understanding of the current states of particular industries to determine informal valuations of the equipment. As necessary and where available, management will utilize valuations by independent appraisers. The large majority of leases with residual values contain a lease options rider, which requires the lessee to pay the residual value directly, finance the payment of the residual value, or extend the lease term to pay the residual value. In these cases, the residual value is protected and the risk of loss is minimal. There were no losses related to residual values for the three months ended March 31, 2017 and 2016.

[2] Performing = loans/leases accruing and less than 90 days past due. Nonperforming = loans/leases on nonaccrual, accruing loans/leases that are greater than or equal to 90 days past due, and accruing TDRs.

[3] Includes residential real estate loans held for sale totaling $1,051,000 and $1,135,500 as of March 31, 2017, and December 31, 2016, respectively.