Note 4 - Loans and Related Allowance for Loan Loss - Composition of Loan Portfolio (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Loans	$ 703,874	$ 681,897
Loans, percent	100.00%	100.00%
Allowance for loan losses	$ (8,156)	$ (7,803)
Loans, Net	695,718	674,094
Originated Loans [Member]
Loans	$ 567,104	$ 525,352
Loans, percent	100.00%	100.00%
Allowance for loan losses	$ (7,573)	$ (7,283)
Loans, Net	559,531	518,069
Acquired Loans [Member]
Loans	$ 136,770	$ 156,545
Loans, percent	100.00%	100.00%
Allowance for loan losses	$ (583)	$ (520)
Loans, Net	136,187	156,025
Residential Portfolio Segment [Member] \| Real Estate Sector [Member]
Loans	$ 268,431	$ 271,588
Loans, percent	38.10%	39.80%
Residential Portfolio Segment [Member] \| Real Estate Sector [Member] \| Originated Loans [Member]
Loans	$ 193,214	$ 186,077
Loans, percent	34.10%	35.40%
Residential Portfolio Segment [Member] \| Real Estate Sector [Member] \| Acquired Loans [Member]
Loans	$ 75,217	$ 85,511
Loans, percent	55.00%	54.70%
Commercial Portfolio Segment [Member] \| Real Estate Sector [Member]
Loans	$ 203,268	$ 201,010
Loans, percent	28.90%	29.50%
Commercial Portfolio Segment [Member] \| Real Estate Sector [Member] \| Originated Loans [Member]
Loans	$ 150,442	$ 139,894
Loans, percent	26.50%	26.70%
Commercial Portfolio Segment [Member] \| Real Estate Sector [Member] \| Acquired Loans [Member]
Loans	$ 52,826	$ 61,116
Loans, percent	38.70%	39.00%
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member]
Loans	$ 85,749	$ 80,812
Loans, percent	12.20%	11.90%
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member] \| Originated Loans [Member]
Loans	$ 77,217	$ 71,091
Loans, percent	13.60%	13.50%
Commercial Portfolio Segment [Member] \| Commercial and Industrial Sector [Member] \| Acquired Loans [Member]
Loans	$ 8,532	$ 9,721
Loans, percent	6.20%	6.20%
Construction Portfolio Segment [Member] \| Real Estate Sector [Member]
Loans	$ 28,965	$ 10,646
Loans, percent	4.10%	1.60%
Construction Portfolio Segment [Member] \| Real Estate Sector [Member] \| Originated Loans [Member]
Loans	$ 28,965	$ 10,646
Loans, percent	5.10%	2.00%
Construction Portfolio Segment [Member] \| Real Estate Sector [Member] \| Acquired Loans [Member]
Loans
Consumer Portfolio Segment [Member]
Loans	$ 114,017	$ 114,204
Loans, percent	16.20%	16.70%
Consumer Portfolio Segment [Member] \| Originated Loans [Member]
Loans	$ 113,822	$ 114,007
Loans, percent	20.10%	21.70%
Consumer Portfolio Segment [Member] \| Acquired Loans [Member]
Loans	$ 195	$ 197
Loans, percent	0.10%	0.10%
Unallocated Financing Receivables [Member]
Loans	$ 3,444	$ 3,637
Loans, percent	0.50%	0.50%
Unallocated Financing Receivables [Member] \| Originated Loans [Member]
Loans	$ 3,444	$ 3,637
Loans, percent	0.60%	0.70%

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- Definition

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
-Paragraph 11B
-Subparagraph (g)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

+ References

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- Definition

Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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