Note 6 - Loans and the Allowance for Loan Losses - Loans Receivable (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Loans	$ 975,284	$ 810,951
Allowance for loan losses	(8,765)	(8,162)	$ (7,244)
Net loans	966,519	802,789
Commercial Real Estate Portfolio Segment [Member] \| Construction and Land [Member]
Loans	143,535	94,426
Allowance for loan losses	(1,421)	(933)	(600)
Commercial Real Estate Portfolio Segment [Member] \| Farmland [Member]
Loans	10,480	9,217
Allowance for loan losses	(76)	(75)	(30)
Commercial Real Estate Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Loans	337,699	298,057
Allowance for loan losses	(2,323)	(2,314)	(1,416)
Residential Portfolio Segment [Member] \| Real Estate Residential One- to Four-Family [Member]
Loans	157,505	129,052
Allowance for loan losses	(1,284)	(1,228)	(1,021)
Residential Portfolio Segment [Member] \| Multi-family Residential [Member]
Loans	20,717	22,737
Allowance for loan losses	(144)	(172)	(101)
Commercial Portfolio Segment [Member]
Loans	254,427	213,120
Allowance for loan losses	(3,147)	(3,039)	(3,618)
Consumer Portfolio Segment [Member]
Loans	50,921	44,342
Allowance for loan losses	$ (370)	$ (401)	$ (458)

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

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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