Note 5 - Loans (Details) - Troubled Debt Restructuring (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 5 - Loans (Details) - Troubled Debt Restructuring [Line Items]
No. of Loans	60	64
Specific Reserve	$ 11,798	$ 13,284
Commercial Loans [Member] \| Accruing Troubled Debt Restructuring [Member]
Note 5 - Loans (Details) - Troubled Debt Restructuring [Line Items]
No. of Loans	4	9	9
Pre-Modification Recorded Investment	10,539	12,026	3,646
Post-Modification Recorded Investment	10,539	10,860	3,646
Specific Reserve	21	550	1,213
Charge-offs		1,166
Commercial Mortgage Loans [Member] \| Accruing Troubled Debt Restructuring [Member]
Note 5 - Loans (Details) - Troubled Debt Restructuring [Line Items]
No. of Loans	3	5	20
Pre-Modification Recorded Investment	11,817	13,090	62,118
Post-Modification Recorded Investment	11,817	13,090	58,393
Specific Reserve	5,550	329	27
Charge-offs			3,725
Residential Mortgage Loans [Member] \| Accruing Troubled Debt Restructuring [Member]
Note 5 - Loans (Details) - Troubled Debt Restructuring [Line Items]
No. of Loans	7	11	14
Pre-Modification Recorded Investment	2,715	3,736	4,305
Post-Modification Recorded Investment	2,715	3,658	4,223
Specific Reserve	29	103	162
Charge-offs		78	82
Accruing Troubled Debt Restructuring [Member]
Note 5 - Loans (Details) - Troubled Debt Restructuring [Line Items]
No. of Loans	14	25	43
Pre-Modification Recorded Investment	25,071	28,852	70,069
Post-Modification Recorded Investment	25,071	27,608	66,262
Specific Reserve	5,600	982	1,402
Charge-offs		$ 1,244	$ 3,807

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Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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- Definition

Pre-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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Reflects the amount of the write-down related to a troubled debt restructuring.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18845-111554

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Amount of allowance for credit losses related to recorded investment.

+ 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 (a)(3)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=d3e5212-111524

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