Note 8 - Loans - Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans receivable	$ 1,182,222	$ 827,563
Allowance for loan losses	(9,836)	(9,309)	$ (8,856)
Loans, net	1,172,386	818,254
Residential Portfolio Segment [Member]
Loans receivable	586,580	456,806
Allowance for loan losses	(4,182)	(3,986)	(3,963)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Senior Lien [Member]
Loans receivable	510,641	372,339
Allowance for loan losses	(3,405)	(3,156)	(3,200)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Junior Lien [Member]
Loans receivable	27,503	25,450
Allowance for loan losses	(384)	(325)	(224)
Residential Portfolio Segment [Member] \| Home Equity Line of Credit 1 [Member]
Loans receivable	33,638	34,319
Allowance for loan losses	(276)	(302)	(296)
Residential Portfolio Segment [Member] \| Construction Loans [Member]
Loans receivable	14,798	24,698
Allowance for loan losses	(117)	(203)	(243)
Commercial Portfolio Segment [Member]
Loans receivable	578,901	353,627
Allowance for loan losses	(4,788)	(4,591)	(4,235)
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans receivable	301,227	162,611
Allowance for loan losses	(1,921)	(2,538)	(2,584)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans receivable	33,555	11,962
Allowance for loan losses	(966)	(110)	(150)
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Loans receivable	126,374	91,856
Allowance for loan losses	(1,391)	(1,553)	(1,065)
Commercial Portfolio Segment [Member] \| Political Subdivisions [Member]
Loans receivable	53,570	53,263
Allowance for loan losses	0	0
Commercial Portfolio Segment [Member] \| Loans Secured by Farmland [Member]
Loans receivable	12,251	7,146
Allowance for loan losses	(158)	(102)	(105)
Commercial Portfolio Segment [Member] \| Multifamily 5 or More Residential [Member]
Loans receivable	31,070	7,180
Allowance for loan losses	(156)	(114)	(172)
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Loans receivable	4,319	5,659
Allowance for loan losses	(41)	(46)	(57)
Commercial Portfolio Segment [Member] \| Other Commercial Loans [Member]
Loans receivable	16,535	13,950
Allowance for loan losses	(155)	(128)	(102)
Consumer Portfolio Segment [Member]
Loans receivable	16,741	17,130
Allowance for loan losses	$ (281)	$ (233)	$ (159)

Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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