Note 7 - Loans and Related Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
ALLL balance, period start	$ 6,720	$ 6,357	$ 6,598	$ 6,385
Charge-offs	(474)	(275)	(682)	(452)
Recoveries	189	179	354	223
Provision	170	105	335	210
ALLL balance, period end	6,605	6,366	6,605	6,366
Commercial And Industrial [Member]
ALLL balance, period start	616	583	448	867
Charge-offs	(415)	(3)	(435)	(123)
Recoveries	65	9	144	47
Provision	347	(105)	456	(307)
ALLL balance, period end	613	484	613	484
Real Estate Construction Porfolio Segment [Member]
ALLL balance, period start	186	247	172	276
Charge-offs
Recoveries	6		22
Provision	10	(88)	8	(117)
ALLL balance, period end	202	159	202	159
Real Estate Mortgage Portfolio Segment [Member] \| Residential Loan [Member]
ALLL balance, period start	2,523	2,716	2,818	3,139
Charge-offs	(7)	(202)	(74)	(244)
Recoveries	7	28	14	31
Provision	(756)	246	(991)	(138)
ALLL balance, period end	1,767	2,788	1,767	2,788
Real Estate Mortgage Portfolio Segment [Member] \| Commercial Loans [Member]
ALLL balance, period start	3,378	2,783	3,135	2,078
Charge-offs		(70)	(19)	(70)
Recoveries		140		140
Provision	634	56	896	761
ALLL balance, period end	4,012	2,909	4,012	2,909
Consumer Portfolio Segment [Member]
ALLL balance, period start	17	28	25	25
Charge-offs	(52)		(154)	(15)
Recoveries	111	2	174	5
Provision	(65)	(4)	(34)	11
ALLL balance, period end	$ 11	$ 26	$ 11	$ 26

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

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

+ References

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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
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Amount of expense related to estimated loss from loan and lease transactions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
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