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Note 1 - Significant Accounting Policies (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2016 USD ($) shares | Mar. 31, 2015 shares | Dec. 31, 2015 USD ($)
Note 1 - Significant Accounting Policies (Details) [Line Items] |  |  |
Number of Unconsolidated Business Trusts Formed to Issue Trust Preferred Securities | 5 |  |
Interest Income on Commercial and Mortgage Loans, Discontinued Period | 90 days |  |
Maximum Delinquency Period for Consumer and Credit Card Loans to be Charged-off | 120 days |  |
Loans Receivable Held-for-sale, Net, Not Part of Disposal Group, Mortgage (in Dollars) | $ | $ 0.5 |  | $ 1.3
Employee Stock Option [Member] |  |  |
Note 1 - Significant Accounting Policies (Details) [Line Items] |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 10,000 | 118,000 |
Mortgage Loans [Member] |  |  |
Note 1 - Significant Accounting Policies (Details) [Line Items] |  |  |
Servicing Asset (in Dollars) | $ | $ 600.0 |  |
Restricted Stock [Member] |  |  |
Note 1 - Significant Accounting Policies (Details) [Line Items] |  |  |
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights | 150,000 | 101,000 |
Employee Stock Option [Member] |  |  |
Note 1 - Significant Accounting Policies (Details) [Line Items] |  |  |
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements | 118,000 | 121,000 |
Core Deposits [Member] |  |  |
Note 1 - Significant Accounting Policies (Details) [Line Items] |  |  |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life | 10 years |  |

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