Note 4 - Loans - Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Loans	$ 750,985	$ 711,902
Deferred loan fees and costs, net	(792)	(997)
Allowance for loan losses	(9,146)	(8,685)	$ (8,166)
Net loans	741,047	702,220
Commercial Real Estate Portfolio Segment [Member]
Loans	607,002	554,519
Allowance for loan losses	(7,170)	(6,580)	(6,331)
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans	53,169	20,263
Commercial Real Estate Portfolio Segment [Member] \| Mortgage Loans [Member]
Loans	475,146	460,701
Commercial Real Estate Portfolio Segment [Member] \| Land Loans [Member]
Loans	8,367	10,951
Commercial Real Estate Portfolio Segment [Member] \| Farmland Loans [Member]
Loans	70,320	62,604
Commercial Portfolio Segment [Member]
Loans	77,704	82,252
Allowance for loan losses	(1,000)	(1,065)	(813)
Consumer Portfolio Segment [Member]
Loans	1,274	1,314
Allowance for loan losses	(38)	(39)	(27)
Residential Portfolio Segment [Member]
Loans	36,647	35,741
Allowance for loan losses	(306)	(304)	(300)
Agriculture [Member]
Loans	28,358	38,076
Allowance for loan losses	$ (525)	$ (693)	$ (693)

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

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