Note 7 - Loans (Details) (USD $)	3 Months Ended
Mar. 31, 2015	Dec. 31, 2014
Note 7 - Loans (Details) [Line Items]
Impaired Financing Receivable, Recorded Investment	$ 180,717,000	$ 174,519,000
Percentage of Charge-off to Contractual Balances for Impaired Loans	17.00%	17.10%
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0
Reduction of Stated Interest Rate [Member] \| Minimum [Member]
Note 7 - Loans (Details) [Line Items]
Troubled Debt Restructurings Length of Modifications	7 months
Reduction of Stated Interest Rate [Member] \| Maximum [Member]
Note 7 - Loans (Details) [Line Items]
Troubled Debt Restructurings Length of Modifications	2 years
Commercial Loans [Member] \| Accruing Troubled Debt Restructuring [Member]
Note 7 - Loans (Details) [Line Items]
Financing Receivable, Modifications, Recorded Investment	16,722,000	16,506,000
Commercial Loans [Member]
Note 7 - Loans (Details) [Line Items]
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	598,000
Financing Receivable, Modifications, Subsequent Default, Recorded Investment	10,200,000
Accruing Troubled Debt Restructuring [Member]
Note 7 - Loans (Details) [Line Items]
Financing Receivable, Modifications, Recorded Investment	100,400,000	104,300,000
Allowance for Credit Losses, Change in Method of Calculating Impairment	6,900,000	6,500,000
Financing Receivables, Impaired, Troubled Debt Restructuring, Write-down	148,000
Non Accruing Troubled Debt Restructuring [Member]
Note 7 - Loans (Details) [Line Items]
Financing Receivable, Modifications, Recorded Investment	44,500,000	41,600,000
Allowance for Credit Losses, Change in Method of Calculating Impairment	2,100,000	4,900,000
Nonaccrual Loans [Member]
Note 7 - Loans (Details) [Line Items]
Impaired Financing Receivable, Recorded Investment	80,300,000	70,200,000
Accruing Troubled Debt Restructuring [Member]
Note 7 - Loans (Details) [Line Items]
Impaired Financing Receivable, Recorded Investment	100,400,000
Financing Receivable, Modifications, Recorded Investment	100,393,000	104,356,000
Nonaccrual Loans Held for Sale [Member]
Note 7 - Loans (Details) [Line Items]
Impaired Financing Receivable, Recorded Investment		$ 104,300,000
Minimum [Member]
Note 7 - Loans (Details) [Line Items]
Period Loan is in Payment Default	60 days
Maximum [Member]
Note 7 - Loans (Details) [Line Items]
Period Loan is in Payment Default	90 days

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Percentage of charge-off to contractual balances for impaired loans.

+ References

No definition available.

+ Details

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- Definition

The period the loan is in payment default.

+ References

No definition available.

+ Details

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- Definition

Troubled debt restructurings length of modifications.

+ References

No definition available.

+ Details

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- Definition

Amount of allowance for credit losses related to receivables which had been measured under a general allowance for credit losses methodology that are now identified as troubled debt restructurings.

+ References

No definition available.

+ Details

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- Definition

The amount of the outstanding recorded investment related to 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 40

-Section 50

-Paragraph 4

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

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- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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- Definition

Amount of investment related to financing receivables modified by troubled debt restructurings within the previous 12 months, for which there was a payment default.

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

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 14A

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953550-111524

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