Note 4 - Loans - Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Loans	$ 711,902	$ 662,544
Deferred loan fees and costs, net	(997)	(1,389)
Allowance for loan losses	(8,685)	(8,166)	$ (7,832)
	702,220	652,989
Commercial Real Estate Portfolio Segment [Member]
Loans	554,519	517,150
Allowance for loan losses	(6,580)	(6,331)	(6,185)
Commercial Real Estate Portfolio Segment [Member] \| Construction Loans [Member]
Loans	20,263	31,265
Commercial Real Estate Portfolio Segment [Member] \| Mortgage Loans [Member]
Loans	460,701	417,138
Commercial Real Estate Portfolio Segment [Member] \| Land Loans [Member]
Loans	10,951	10,072
Commercial Real Estate Portfolio Segment [Member] \| Farmland Loans [Member]
Loans	62,604	58,675
Commercial Portfolio Segment [Member]
Loans	82,252	69,610
Allowance for loan losses	(1,065)	(813)	(697)
Consumer Portfolio Segment [Member]
Loans	1,314	689
Allowance for loan losses	(39)	(27)	(51)
Residential Portfolio Segment [Member]
Loans	35,741	37,161
Allowance for loan losses	(304)	(300)	(325)
Agriculture [Member]
Loans	38,076	37,934
Allowance for loan losses	$ (693)	$ (693)	$ (504)

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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