Note 4 - Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Balance	$ 7,996	$ 7,315	$ 7,499	$ 7,699
Provision for loan losses	(23)	175	733	320
Loans charged off	(751)	(909)	(1,338)	(1,866)
Recoveries	417	371	745	799
Balance	7,639	6,952	7,639	6,952
Residential Portfolio Segment [Member]
Balance	2,059	1,392	1,470	939
Provision for loan losses	(14)	(68)	580	377
Loans charged off	(177)	(73)	(237)	(146)
Recoveries	18	49	73	130
Balance	1,886	1,300	1,886	1,300
Commercial Real Estate Portfolio Segment [Member]
Balance	2,423	2,729	2,978	4,315
Provision for loan losses	(82)	(89)	(663)	(1,176)
Loans charged off		(53)	(1)	(612)
Recoveries	51	226	78	286
Balance	2,392	2,813	2,392	2,813
Commercial and Industrial Portfolio Segment [Member]
Balance	1,373	1,360	1,024	907
Provision for loan losses	(317)	(35)	(1)	350
Loans charged off		(399)	(4)	(403)
Recoveries	186	6	223	78
Balance	1,242	932	1,242	932
Consumer Portfolio Segment [Member]
Balance	2,141	1,834	2,027	1,538
Provision for loan losses	390	367	817	769
Loans charged off	(574)	(384)	(1,096)	(705)
Recoveries	162	90	371	305
Balance	$ 2,119	$ 1,907	$ 2,119	$ 1,907

A valuation allowance for financing receivables that are expected to be uncollectible.

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Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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