Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Mar. 31, 2017	Mar. 31, 2016	Dec. 31, 2016
Balance	$ 8,300	$ 8,297	$ 8,297
Charge-offs	(143)	(453)	(1,806)
Recoveries	45	60	159
Provision for loan losses	59	203	1,650
Balance	8,261	8,107	8,300
Real Estate Construction Portfolio Segment[Member]
Balance	438	576	576
Charge-offs	0	(29)	(29)
Recoveries	0	0	0
Provision for loan losses	(61)	(93)	(109)
Balance	377	454	438
Consumer Real Estate Portfolio Segment [Member]
Balance	1,830	1,866	1,866
Charge-offs	0	(22)	(133)
Recoveries	0	1	2
Provision for loan losses	(84)	(115)	95
Balance	1,746	1,730	1,830
Commercial Real Estate Portfolio Segment [Member]
Balance	3,738	4,109	4,109
Charge-offs	(30)	(124)	(488)
Recoveries	12	38	83
Provision for loan losses	(103)	(74)	34
Balance	3,617	3,949	3,738
Commercial Non Real Estate Segment [Member]
Balance	1,063	655	655
Charge-offs	0	(211)	(883)
Recoveries	4	0	10
Provision for loan losses	75	308	1,281
Balance	1,142	752	1,063
Public Sector and IDA Portfolio Segment[Member]
Balance	330	436	436
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for loan losses	87	(25)	(106)
Balance	417	411	330
Consumer Non Real Estate Portfolio Segment [Member]
Balance	644	627	627
Charge-offs	(113)	(67)	(273)
Recoveries	29	21	64
Provision for loan losses	56	3	226
Balance	616	584	644
Unallocated Financing Receivables [Member]
Balance	257	28	28
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for loan losses	89	199	229
Balance	$ 346	$ 227	$ 257

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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

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Amount of expense related to estimated loss from loan and lease transactions.

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