Note 8 - Impaired Loans (Details) - USD ($)	6 Months Ended	12 Months Ended
Jun. 30, 2016	Dec. 31, 2015
Commercial Portfolio Segment [Member] \| Commercial and Industrial [Member]
Recorded investment - with no specific allowance	$ 3,436,000	$ 3,629,000
Unpaid principal balance - with no specific allowance	3,772,000	3,923,000
Recorded investment - with an allowance	706,000	957,000
Unpaid principal balance - with an allowance	848,000	1,086,000
Related allowance	518,000	712,000
Recorded investment	4,142,000	4,586,000
Unpaid principal balance	4,620,000	5,009,000
Average recorded investment	4,370,000	6,108,000
Interest income recognized	35,000	169,000
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Recorded investment - with no specific allowance	508,000	364,000
Unpaid principal balance - with no specific allowance	540,000	364,000
Recorded investment - with an allowance	0	0
Unpaid principal balance - with an allowance	0	0
Related allowance	0	0
Recorded investment	508,000	364,000
Unpaid principal balance	540,000	364,000
Average recorded investment	429,000	396,000
Interest income recognized	10,000	20,000
Commercial Portfolio Segment [Member] \| Secured by Commercial Real Estate [Member]
Recorded investment - with no specific allowance	5,360,000	6,932,000
Unpaid principal balance - with no specific allowance	5,766,000	7,416,000
Recorded investment - with an allowance	810,000	66,000
Unpaid principal balance - with an allowance	957,000	66,000
Related allowance	60,000	14,000
Recorded investment	6,170,000	6,998,000
Unpaid principal balance	6,723,000	7,482,000
Average recorded investment	6,426,000	7,370,000
Interest income recognized	67,000	149,000
Commercial Portfolio Segment [Member] \| Secured by Residential Real Estate [Member]
Recorded investment - with no specific allowance	1,009,000	942,000
Unpaid principal balance - with no specific allowance	1,537,000	1,653,000
Recorded investment - with an allowance	969,000	1,171,000
Unpaid principal balance - with an allowance	1,097,000	1,279,000
Related allowance	158,000	203,000
Recorded investment	1,978,000	2,113,000
Unpaid principal balance	2,634,000	2,932,000
Average recorded investment	2,013,000	1,544,000
Interest income recognized	7,000
State and Political Subdivisions Portfolio Segment [Member]
Recorded investment - with no specific allowance	0	0
Unpaid principal balance - with no specific allowance	0	0
Recorded investment - with an allowance	0	0
Unpaid principal balance - with an allowance	0	0
Related allowance	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment
Interest income recognized
Finance Leases Portfolio Segment [Member]
Recorded investment - with no specific allowance	13,000	3,000
Unpaid principal balance - with no specific allowance	23,000	3,000
Recorded investment - with an allowance	97,000	143,000
Unpaid principal balance - with an allowance	98,000	145,000
Related allowance	45,000	20,000
Recorded investment	110,000	146,000
Unpaid principal balance	121,000	148,000
Average recorded investment	112,000	43,000
Interest income recognized		1,000
Retail Portfolio Segment [Member] \| Family Residential Mortgages [Member]
Recorded investment - with no specific allowance	385,000	393,000
Unpaid principal balance - with no specific allowance	401,000	406,000
Recorded investment - with an allowance	183,000	190,000
Unpaid principal balance - with an allowance	195,000	197,000
Related allowance	22,000	25,000
Recorded investment	568,000	583,000
Unpaid principal balance	596,000	603,000
Average recorded investment	576,000	448,000
Interest income recognized	5,000	6,000
Retail Portfolio Segment [Member] \| Home Equity Loan [Member]
Recorded investment - with no specific allowance	128,000	151,000
Unpaid principal balance - with no specific allowance	185,000	201,000
Recorded investment - with an allowance	0	0
Unpaid principal balance - with an allowance	0	0
Related allowance	0	0
Recorded investment	128,000	151,000
Unpaid principal balance	185,000	201,000
Average recorded investment	139,000	135,000
Interest income recognized	1,000	1,000
Retail Portfolio Segment [Member] \| Consumer Loans [Member]
Recorded investment - with no specific allowance		0
Unpaid principal balance - with no specific allowance	0	0
Recorded investment - with an allowance	0	0
Unpaid principal balance - with an allowance	0	0
Related allowance	0	0
Recorded investment	0	0
Unpaid principal balance	0	0
Average recorded investment		2,000
Interest income recognized
Recorded investment - with no specific allowance	10,839,000	12,414,000
Unpaid principal balance - with no specific allowance	12,224,000	13,966,000
Recorded investment - with an allowance	2,765,000	2,527,000
Unpaid principal balance - with an allowance	3,195,000	2,773,000
Related allowance	803,000	974,000
Recorded investment	13,604,000	14,941,000
Unpaid principal balance	15,419,000	16,739,000
Average recorded investment	14,065,000	16,046,000
Interest income recognized	$ 125,000	$ 346,000

Average amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 17
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5258-111524

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- Definition

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

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- Definition

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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