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Note 4 - Loans and Allowance for Loan Losses - Changes in Allowance for Loan Losses and Recorded Investment in Loans (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016
Beginning balance				$ 4,856					$ 4,856
Provision (reduction in reserve) for loan losses	$ 523	$ 373	$ 576	515	$ 1,814	$ 680	$ 536	$ 167	1,987	$ 3,197
Ending balance	4,774				4,856				4,774	4,856
Total allowance for loan losses	4,774			4,856	4,856				4,774	4,856	$ 4,774	$ 4,856
Total loans receivable											357,458	334,781
Real Estate [Member] | Construction, Land Development and Other Land Loans [Member]
Total loans receivable											26,143	23,772
Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Total loans receivable											45,073	46,679
Real Estate [Member] | Secured by Multi-family Residential Properties [Member]
Total loans receivable											16,579	16,627
Real Estate [Member] | Secured by Non-farm, Non-residential Properties [Member]
Total loans receivable											105,133	102,112
Real Estate [Member] | Other Real Estate Loans [Member]
Total loans receivable											190	234
Commercial and Industrial Loans [Member]
Total loans receivable											69,969	57,963
Consumer Portfolio Segment [Member] | Consumer Loans [Member]
Total loans receivable											39,300	42,619
Consumer Portfolio Segment [Member] | Indirect Sales [Member]
Total loans receivable											55,071	44,775
FUSB [Member]
Beginning balance				2,409				1,329	2,409	1,329
Charge-offs									(79)	(151)
Recoveries									247	346
Provision (reduction in reserve) for loan losses									(130)	885
Ending balance	2,447				2,409				2,447	2,409
Individually evaluated for impairment											98	535
Collectively evaluated for impairment											2,349	1,874
Total allowance for loan losses	2,447			2,409	2,409			1,329	2,447	2,409	2,447	2,409
Individually evaluated for impairment											791	2,103
Collectively evaluated for impairment											256,712	237,766
Total loans receivable											257,503	239,869
FUSB [Member] | Real Estate [Member] | Construction, Land Development and Other Land Loans [Member]
Beginning balance				535				110	535	110
Charge-offs
Recoveries										200
Provision (reduction in reserve) for loan losses									(332)	225
Ending balance	203				535				203	535
Individually evaluated for impairment												423
Collectively evaluated for impairment											203	112
Total allowance for loan losses	203			535	535			110	535	535	203	535
Individually evaluated for impairment												1,361
Collectively evaluated for impairment											26,143	22,411
Total loans receivable											26,143	23,772
FUSB [Member] | Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Beginning balance				304				138	304	138
Charge-offs										(66)
Recoveries									103	23
Provision (reduction in reserve) for loan losses									(169)	209
Ending balance	238				304				238	304
Individually evaluated for impairment											5	5
Collectively evaluated for impairment											233	299
Total allowance for loan losses	238			304	304			138	304	304	238	304
Individually evaluated for impairment											187	193
Collectively evaluated for impairment											34,085	32,762
Total loans receivable											34,272	32,955
FUSB [Member] | Real Estate [Member] | Secured by Multi-family Residential Properties [Member]
Beginning balance				88				29	88	29
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses									28	59
Ending balance	116				88				116	88
Individually evaluated for impairment
Collectively evaluated for impairment											116	88
Total allowance for loan losses	116			88	88			29	88	88	116	88
Individually evaluated for impairment
Collectively evaluated for impairment											16,579	16,627
Total loans receivable											16,579	16,627
FUSB [Member] | Real Estate [Member] | Secured by Non-farm, Non-residential Properties [Member]
Beginning balance				903				351	903	351
Charge-offs										(40)
Recoveries									69
Provision (reduction in reserve) for loan losses									(195)	592
Ending balance	777				903				777	903
Individually evaluated for impairment											21	107
Collectively evaluated for impairment											756	796
Total allowance for loan losses	777			903	903			351	903	903	777	903
Individually evaluated for impairment											532	549
Collectively evaluated for impairment											104,601	101,563
Total loans receivable											105,133	102,112
FUSB [Member] | Real Estate [Member] | Other Real Estate Loans [Member]
Beginning balance				2				1	2	1
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses										1
Ending balance	2				2				2	2
Individually evaluated for impairment
Collectively evaluated for impairment											2	2
Total allowance for loan losses	2			2	2			1	2	2	2	2
Individually evaluated for impairment
Collectively evaluated for impairment											190	234
Total loans receivable											190	234
FUSB [Member] | Commercial and Industrial Loans [Member]
Beginning balance				527				659	527	659
Charge-offs									(16)	(2)
Recoveries									19	73
Provision (reduction in reserve) for loan losses									519	(203)
Ending balance	1,049				527				1,049	527
Individually evaluated for impairment											72
Collectively evaluated for impairment											977	527
Total allowance for loan losses	1,049			527	527			659	527	527	1,049	527
Individually evaluated for impairment											72
Collectively evaluated for impairment											69,897	57,963
Total loans receivable											69,969	57,963
FUSB [Member] | Consumer Portfolio Segment [Member]
Total loans receivable											5,217	6,206
FUSB [Member] | Consumer Portfolio Segment [Member] | Consumer Loans [Member]
Beginning balance				50				41	50	41
Charge-offs									(63)	(43)
Recoveries									56	50
Provision (reduction in reserve) for loan losses									19	2
Ending balance	62				50				62	50
Individually evaluated for impairment
Collectively evaluated for impairment											62	50
Total allowance for loan losses	62			50	50			41	50	50	62	50
Individually evaluated for impairment
Collectively evaluated for impairment											5,217	6,206
Total loans receivable											5,217	6,206
FUSB [Member] | Consumer Portfolio Segment [Member] | Indirect Sales [Member]
Beginning balance
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses
Ending balance
Individually evaluated for impairment
Collectively evaluated for impairment
Total allowance for loan losses
Individually evaluated for impairment
Collectively evaluated for impairment
Total loans receivable
ALC [Member]
Beginning balance				2,447				2,452	2,447	2,452
Charge-offs									(2,912)	(3,026)
Recoveries									675	710
Provision (reduction in reserve) for loan losses									2,117	2,311
Ending balance	2,327				2,447				2,327	2,447
Individually evaluated for impairment
Collectively evaluated for impairment											2,327	2,447
Total allowance for loan losses	2,327			2,447	2,447			2,452	2,327	2,447	2,327	2,447
Individually evaluated for impairment
Collectively evaluated for impairment											99,955	94,912
Total loans receivable											99,955	94,912
ALC [Member] | Real Estate [Member] | Construction, Land Development and Other Land Loans [Member]
Beginning balance
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses
Ending balance
Individually evaluated for impairment
Collectively evaluated for impairment
Total allowance for loan losses
Individually evaluated for impairment
Collectively evaluated for impairment
Total loans receivable
ALC [Member] | Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Beginning balance				107				250	107	250
Charge-offs									(28)	(56)
Recoveries									32	39
Provision (reduction in reserve) for loan losses									(59)	(126)
Ending balance	52				107				52	107
Individually evaluated for impairment
Collectively evaluated for impairment											52	107
Total allowance for loan losses	52			107	107			250	107	107	52	107
Individually evaluated for impairment
Collectively evaluated for impairment											10,801	13,724
Total loans receivable											10,801	13,724
ALC [Member] | Real Estate [Member] | Secured by Multi-family Residential Properties [Member]
Beginning balance
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses
Ending balance
Individually evaluated for impairment
Collectively evaluated for impairment
Total allowance for loan losses
Individually evaluated for impairment
Collectively evaluated for impairment
Total loans receivable
ALC [Member] | Real Estate [Member] | Secured by Non-farm, Non-residential Properties [Member]
Beginning balance
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses
Ending balance
Individually evaluated for impairment
Collectively evaluated for impairment
Total allowance for loan losses
Individually evaluated for impairment
Collectively evaluated for impairment
Total loans receivable
ALC [Member] | Real Estate [Member] | Other Real Estate Loans [Member]
Beginning balance
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses
Ending balance
Individually evaluated for impairment
Collectively evaluated for impairment
Total allowance for loan losses
Individually evaluated for impairment
Collectively evaluated for impairment
Total loans receivable
ALC [Member] | Commercial and Industrial Loans [Member]
Beginning balance
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses
Ending balance
Individually evaluated for impairment
Collectively evaluated for impairment
Total allowance for loan losses
Individually evaluated for impairment
Collectively evaluated for impairment
Total loans receivable
ALC [Member] | Consumer Portfolio Segment [Member] | Consumer Loans [Member]
Beginning balance				1,717				1,584	1,717	1,584
Charge-offs									(2,297)	(2,218)
Recoveries									545	451
Provision (reduction in reserve) for loan losses									1,688	1,900
Ending balance	1,653				1,717				1,653	1,717
Individually evaluated for impairment
Collectively evaluated for impairment											1,653	1,717
Total allowance for loan losses	1,653			1,717	1,717			1,584	1,717	1,717	1,653	1,717
Individually evaluated for impairment
Collectively evaluated for impairment											34,083	36,413
Total loans receivable											34,083	36,413
ALC [Member] | Consumer Portfolio Segment [Member] | Indirect Sales [Member]
Beginning balance				623				618	623	618
Charge-offs									(587)	(752)
Recoveries									98	220
Provision (reduction in reserve) for loan losses									488	537
Ending balance	622				623				622	623
Individually evaluated for impairment
Collectively evaluated for impairment											622	623
Total allowance for loan losses	622			623	623			618	623	623	622	623
Individually evaluated for impairment
Collectively evaluated for impairment											55,071	44,775
Total loans receivable											55,071	44,775
FUSB and ALC [Member]
Beginning balance				4,856				3,781	4,856	3,781
Charge-offs									(2,991)	(3,177)
Recoveries									922	1,056
Provision (reduction in reserve) for loan losses									1,987	3,196
Ending balance	4,774				4,856				4,774	4,856
Individually evaluated for impairment											98	535
Collectively evaluated for impairment											4,676	4,321
Total allowance for loan losses	4,774			4,856	4,856			3,781	4,856	4,856	4,774	4,856
Individually evaluated for impairment											791	2,103
Collectively evaluated for impairment											356,667	332,678
Total loans receivable											357,458	334,781
FUSB and ALC [Member] | Real Estate [Member] | Construction, Land Development and Other Land Loans [Member]
Beginning balance				535				110	535	110
Charge-offs
Recoveries										200
Provision (reduction in reserve) for loan losses									(332)	225
Ending balance	203				535				203	535
Individually evaluated for impairment												423
Collectively evaluated for impairment											203	112
Total allowance for loan losses	203			535	535			110	535	535	203	535
Individually evaluated for impairment												1,361
Collectively evaluated for impairment											26,143	22,411
Total loans receivable											26,143	23,772
FUSB and ALC [Member] | Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Beginning balance				411				388	411	388
Charge-offs									(28)	(122)
Recoveries									135	62
Provision (reduction in reserve) for loan losses									(228)	83
Ending balance	290				411				290	411
Individually evaluated for impairment											5	5
Collectively evaluated for impairment											285	406
Total allowance for loan losses	290			411	411			388	411	411	290	411
Individually evaluated for impairment											187	193
Collectively evaluated for impairment											44,886	46,486
Total loans receivable											45,073	46,679
FUSB and ALC [Member] | Real Estate [Member] | Secured by Multi-family Residential Properties [Member]
Beginning balance				88				29	88	29
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses									28	59
Ending balance	116				88				116	88
Individually evaluated for impairment
Collectively evaluated for impairment											116	88
Total allowance for loan losses	116			88	88			29	88	88	116	88
Individually evaluated for impairment
Collectively evaluated for impairment											16,579	16,627
Total loans receivable											16,579	16,627
FUSB and ALC [Member] | Real Estate [Member] | Secured by Non-farm, Non-residential Properties [Member]
Beginning balance				903				351	903	351
Charge-offs										(40)
Recoveries									69
Provision (reduction in reserve) for loan losses									(195)	592
Ending balance	777				903				777	903
Individually evaluated for impairment											21	107
Collectively evaluated for impairment											756	796
Total allowance for loan losses	777			903	903			351	903	903	777	903
Individually evaluated for impairment											532	549
Collectively evaluated for impairment											104,601	101,563
Total loans receivable											105,133	102,112
FUSB and ALC [Member] | Real Estate [Member] | Other Real Estate Loans [Member]
Beginning balance				2				1	2	1
Charge-offs
Recoveries
Provision (reduction in reserve) for loan losses										1
Ending balance	2				2				2	2
Individually evaluated for impairment
Collectively evaluated for impairment											2	2
Total allowance for loan losses	2			2	2			1	2	2	2	2
Individually evaluated for impairment
Collectively evaluated for impairment											190	234
Total loans receivable											190	234
FUSB and ALC [Member] | Commercial and Industrial Loans [Member]
Beginning balance				527				659	527	659
Charge-offs									(16)	(2)
Recoveries									19	73
Provision (reduction in reserve) for loan losses									519	(203)
Ending balance	1,049				527				1,049	527
Individually evaluated for impairment											72
Collectively evaluated for impairment											977	527
Total allowance for loan losses	1,049			527	527			659	527	527	1,049	527
Individually evaluated for impairment											72
Collectively evaluated for impairment											69,897	57,963
Total loans receivable											69,969	57,963
FUSB and ALC [Member] | Consumer Portfolio Segment [Member] | Consumer Loans [Member]
Beginning balance				1,767				1,625	1,767	1,625
Charge-offs									(2,360)	(2,261)
Recoveries									601	501
Provision (reduction in reserve) for loan losses									1,707	1,902
Ending balance	1,715				1,767				1,715	1,767
Individually evaluated for impairment
Collectively evaluated for impairment											1,715	1,767
Total allowance for loan losses	1,715			1,767	1,767			1,625	1,767	1,767	1,715	1,767
Individually evaluated for impairment
Collectively evaluated for impairment											39,300	42,619
Total loans receivable											39,300	42,619
FUSB and ALC [Member] | Consumer Portfolio Segment [Member] | Indirect Sales [Member]
Beginning balance				623				618	623	618
Charge-offs									(587)	(752)
Recoveries									98	220
Provision (reduction in reserve) for loan losses									488	537
Ending balance	622				623				622	623
Individually evaluated for impairment
Collectively evaluated for impairment											622	623
Total allowance for loan losses	$ 622			$ 623	$ 623			$ 618	$ 623	$ 623	622	623
Individually evaluated for impairment
Collectively evaluated for impairment											55,071	44,775
Total loans receivable											$ 55,071	$ 44,775

X

- Definition

Represents the amount of provision (reduction in reserve) for loan losses during the period.

+ References

No definition available.

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Amount of direct write-downs of accounts receivable charged against the allowance.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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