Note 5 - Loans and Allowance for Loan Losses (Details) - Impaired Loans (USD $)	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	$ 19,019,000	$ 22,515,000
Loans with no specific allowance recorded, unpaid principal balance	20,485,000	23,404,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)	2,058,000	5,102,000
Loans with an allowance recorded, unpaid principal balance	2,359,000	5,609,000
Loans, related allowance	1,194,000	2,022,000
Total:
Loans, recorded investment (after charge-offs)	21,077,000	27,617,000
Loans, unpaid principal balance	22,844,000	29,013,000
Loans, related allowance	1,194,000	2,022,000
Loans, average recorded investment	25,768,000	29,254,000
Loans, interest income recognized	683,000	560,000
Commercial and Industrial [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	5,894,000	8,222,000
Loans with no specific allowance recorded, unpaid principal balance	6,056,000	8,417,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)	1,221,000	2,082,000
Loans with an allowance recorded, unpaid principal balance	1,419,000	2,350,000
Loans, related allowance	1,095,000	1,106,000
Total:
Loans, recorded investment (after charge-offs)	7,115,000	10,304,000
Loans, unpaid principal balance	7,475,000	10,767,000
Loans, related allowance	1,095,000	1,106,000
Loans, average recorded investment	9,305,000	6,732,000
Loans, interest income recognized	331,000	34,000
Commercial Construction [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	362,000	916,000
Loans with no specific allowance recorded, unpaid principal balance	444,000	1,140,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)		435,000
Loans with an allowance recorded, unpaid principal balance		493,000
Loans, related allowance		121,000
Total:
Loans, recorded investment (after charge-offs)	362,000	1,351,000
Loans, unpaid principal balance	444,000	1,633,000
Loans, related allowance		121,000
Loans, average recorded investment	1,050,000	3,179,000
Loans, interest income recognized	2,000	46,000
Commercial:Secured by Commercial Real Estate [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	11,546,000	12,251,000
Loans with no specific allowance recorded, unpaid principal balance	12,198,000	12,568,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)		37,000
Loans with an allowance recorded, unpaid principal balance		37,000
Loans, related allowance		9,000
Total:
Loans, recorded investment (after charge-offs)	11,546,000	12,288,000
Loans, unpaid principal balance	12,198,000	12,605,000
Loans, related allowance		9,000
Loans, average recorded investment	12,304,000	13,765,000
Loans, interest income recognized	344,000	399,000
Commercial Secured By Residential Real Estate [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	903,000	728,000
Loans with no specific allowance recorded, unpaid principal balance	1,427,000	839,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)	664,000	2,105,000
Loans with an allowance recorded, unpaid principal balance	748,000	2,248,000
Loans, related allowance	91,000	639,000
Total:
Loans, recorded investment (after charge-offs)	1,567,000	2,833,000
Loans, unpaid principal balance	2,175,000	3,087,000
Loans, related allowance	91,000	639,000
Loans, average recorded investment	2,452,000	3,090,000
Loans, interest income recognized		23,000
State and Political Subdivisions [Member]
Total:
Loans, average recorded investment		1,636,000
Loans, interest income recognized		53,000
Indirect Lease Financing [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	16,000	13,000
Loans with no specific allowance recorded, unpaid principal balance	16,000	16,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)		24,000
Loans with an allowance recorded, unpaid principal balance		27,000
Loans, related allowance		3,000
Total:
Loans, recorded investment (after charge-offs)	16,000	37,000
Loans, unpaid principal balance	16,000	43,000
Loans, related allowance		3,000
Loans, average recorded investment	26,000	63,000
Loans, interest income recognized	1,000
Retail:1-4 Family Residential Mortgages [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	225,000	250,000
Loans with no specific allowance recorded, unpaid principal balance	250,000	274,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)	116,000	272,000
Loans with an allowance recorded, unpaid principal balance	116,000	284,000
Loans, related allowance	4,000	63,000
Total:
Loans, recorded investment (after charge-offs)	341,000	522,000
Loans, unpaid principal balance	366,000	558,000
Loans, related allowance	4,000	63,000
Loans, average recorded investment	460,000	495,000
Loans, interest income recognized	5,000	5,000
Retail Home Equity Loans and Lines [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	72,000	135,000
Loans with no specific allowance recorded, unpaid principal balance	93,000	150,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)	57,000	131,000
Loans with an allowance recorded, unpaid principal balance	76,000	154,000
Loans, related allowance	4,000	70,000
Total:
Loans, recorded investment (after charge-offs)	129,000	266,000
Loans, unpaid principal balance	169,000	304,000
Loans, related allowance	4,000	70,000
Loans, average recorded investment	169,000	293,000
Retail:Consumer [Member]
With no specific allowance recorded:
Loans with no specific allowance recorded, recorded investment (after charge-offs)	1,000
Loans with no specific allowance recorded, unpaid principal balance	1,000
With an allowance recorded:
Loans with an allowance recorded, recorded investment (after charge-offs)		16,000
Loans with an allowance recorded, unpaid principal balance		16,000
Loans, related allowance		11,000
Total:
Loans, recorded investment (after charge-offs)	1,000	16,000
Loans, unpaid principal balance	1,000	16,000
Loans, related allowance		11,000
Loans, average recorded investment	$ 2,000	$ 1,000

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

+ References

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=35738203&loc=d3e5212-111524

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 17

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5258-111524

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-Section 50

-Paragraph 14A

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