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Note 4 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans (Details) - Troubled Debt Restructurings $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2014 USD ($) | Jun. 30, 2015 USD ($) | Jun. 30, 2014 USD ($)
Financing Receivable, Modifications [Line Items] |  |  |
Number of contracts |  | 0 |
Commercial Real Estate Portfolio Segment [Member] |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of contracts | 1 | 1 | 2
Pre-modification outstanding principal balance | $ 2,484 | $ 1,007 | $ 2,668
Post-modification outstanding principal balance | $ 2,484 | $ 907 | $ 2,693
Commercial Real Estate Portfolio Segment [Member] | Commercial Real Estate, Owner Occupied [Member] |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of contracts |  | 1 | 1
Pre-modification outstanding principal balance |  | $ 1,007 | $ 184
Post-modification outstanding principal balance |  | $ 907 | $ 209
Commercial Real Estate Portfolio Segment [Member] | Multifamily Real Estate [Member] |  |  |
Financing Receivable, Modifications [Line Items] |  |  |
Number of contracts | 1 |  | 1
Pre-modification outstanding principal balance | $ 2,484 |  | $ 2,484
Post-modification outstanding principal balance | $ 2,484 |  | $ 2,484

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