Note 4 - Loans and Allowance for Loan Losses - Loan Portfolio (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Total loans	$ 357,458	$ 334,781
Less: Unearned interest, fees and deferred cost	6,563	7,153
Loans, allowance for loan losses	4,774	4,856
Net loans	346,121	322,772
FUSB [Member]
Total loans	257,503	239,869
Less: Unearned interest, fees and deferred cost	374	218
Loans, allowance for loan losses	2,447	2,409	$ 1,329
Net loans	254,682	237,242
ALC [Member]
Total loans	99,955	94,912
Less: Unearned interest, fees and deferred cost	6,189	6,935
Loans, allowance for loan losses	2,327	2,447	2,452
Net loans	91,439	85,530
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Total loans	26,143	23,772
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member] \| FUSB [Member]
Total loans	26,143	23,772
Loans, allowance for loan losses	203	535	110
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member] \| ALC [Member]
Total loans
Loans, allowance for loan losses
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Total loans	45,073	46,679
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member] \| FUSB [Member]
Total loans	34,272	32,955
Loans, allowance for loan losses	238	304	138
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member] \| ALC [Member]
Total loans	10,801	13,724
Loans, allowance for loan losses	52	107	250
Real Estate [Member] \| Secured by Multi-family Residential Properties [Member]
Total loans	16,579	16,627
Real Estate [Member] \| Secured by Multi-family Residential Properties [Member] \| FUSB [Member]
Total loans	16,579	16,627
Loans, allowance for loan losses	116	88	29
Real Estate [Member] \| Secured by Multi-family Residential Properties [Member] \| ALC [Member]
Total loans
Loans, allowance for loan losses
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member]
Total loans	105,133	102,112
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member] \| FUSB [Member]
Total loans	105,133	102,112
Loans, allowance for loan losses	777	903	351
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member] \| ALC [Member]
Total loans
Loans, allowance for loan losses
Real Estate [Member] \| Other Real Estate Loans [Member]
Total loans	190	234
Real Estate [Member] \| Other Real Estate Loans [Member] \| FUSB [Member]
Total loans	190	234
Loans, allowance for loan losses	2	2	1
Real Estate [Member] \| Other Real Estate Loans [Member] \| ALC [Member]
Total loans
Loans, allowance for loan losses
Commercial and Industrial Loans [Member]
Total loans	69,969	57,963
Commercial and Industrial Loans [Member] \| FUSB [Member]
Total loans	69,969	57,963
Loans, allowance for loan losses	1,049	527	659
Commercial and Industrial Loans [Member] \| ALC [Member]
Total loans
Loans, allowance for loan losses
Consumer Portfolio Segment [Member] \| FUSB [Member]
Total loans	5,217	6,206
Consumer Portfolio Segment [Member] \| Consumer Loans [Member]
Total loans	39,300	42,619
Consumer Portfolio Segment [Member] \| Consumer Loans [Member] \| FUSB [Member]
Total loans	5,217	6,206
Loans, allowance for loan losses	62	50	41
Consumer Portfolio Segment [Member] \| Consumer Loans [Member] \| ALC [Member]
Total loans	34,083	36,413
Loans, allowance for loan losses	1,653	1,717	1,584
Consumer Portfolio Segment [Member] \| Indirect Sales [Member]
Total loans	55,071	44,775
Consumer Portfolio Segment [Member] \| Indirect Sales [Member] \| FUSB [Member]
Total loans
Loans, allowance for loan losses
Consumer Portfolio Segment [Member] \| Indirect Sales [Member] \| ALC [Member]
Total loans	55,071	44,775
Loans, allowance for loan losses	$ 622	$ 623	$ 618

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 of deferred interest and fee income, unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of acquired loans. Excludes amounts for loans and leases covered under loss sharing agreements.

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