Note 7 - Loans - Loans Receivable (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019	Mar. 31, 2019	Dec. 31, 2018
Loans receivable	$ 1,167,473	$ 1,182,222
Allowance for loan losses	(11,330)	(9,836)	$ (8,256)	$ (9,309)
Loans, net	1,156,143	1,172,386
Residential Portfolio Segment [Member]
Loans receivable	581,626	586,580
Allowance for loan losses	(4,383)	(4,182)	(3,991)	(3,986)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Senior Lien [Member]
Loans receivable	508,387	510,641
Allowance for loan losses	(3,572)	(3,405)	(3,178)	(3,156)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member] \| Junior Lien [Member]
Loans receivable	27,028	27,503
Allowance for loan losses	(414)	(384)	(329)	(325)
Residential Portfolio Segment [Member] \| Home Equity Line of Credit 1 [Member]
Loans receivable	32,090	33,638
Allowance for loan losses	(278)	(276)	(286)	(302)
Residential Portfolio Segment [Member] \| Construction Loans [Member]
Loans receivable	14,121	14,798
Allowance for loan losses	(119)	(117)	(198)	(203)
Commercial Portfolio Segment [Member]
Loans receivable	569,331	578,901
Allowance for loan losses	(6,089)	(4,788)	(3,444)	(4,591)
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans receivable	295,860	301,227
Allowance for loan losses	(1,932)	(1,921)	(1,887)	(2,538)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans receivable	33,340	33,555
Allowance for loan losses	(970)	(966)	(114)	(110)
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Loans receivable	132,308	126,374
Allowance for loan losses	(2,645)	(1,391)	(1,069)	(1,553)
Commercial Portfolio Segment [Member] \| Political Subdivisions [Member]
Loans receivable	43,613	53,570
Allowance for loan losses	0	0
Commercial Portfolio Segment [Member] \| Loans Secured by Farmland [Member]
Loans receivable	11,524	12,251
Allowance for loan losses	(144)	(158)	(98)	(102)
Commercial Portfolio Segment [Member] \| Multifamily 5 or More Residential [Member]
Loans receivable	32,370	31,070
Allowance for loan losses	(199)	(156)	(112)	(114)
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Loans receivable	3,886	4,319
Allowance for loan losses	(39)	(41)	(43)	(46)
Commercial Portfolio Segment [Member] \| Other Commercial Loans [Member]
Loans receivable	16,430	16,535
Allowance for loan losses	(160)	(155)	(121)	(128)
Consumer Portfolio Segment [Member]
Loans receivable	16,516	16,741
Allowance for loan losses	$ (273)	$ (281)	$ (236)	$ (233)

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

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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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