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Note 12 - Regulatory Matters (Details) - USD ($) $ / shares in Units, $ in Millions |  |  |  |  |  |  |  |  | 3 Months Ended | 9 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 23, 2015 | Oct. 15, 2015 | Sep. 23, 2015 | Jul. 16, 2015 | Jun. 24, 2015 | Apr. 16, 2015 | Mar. 25, 2015 | Jan. 15, 2015 | Sep. 30, 2015 | Sep. 30, 2014 | Sep. 30, 2015 | Sep. 30, 2014 | Jan. 30, 2015 | Dec. 31, 2014 | Dec. 31, 2009
Note 12 - Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Trust Preferred Securities Included in Tier One Capital (in Dollars) |  |  |  |  |  |  |  |  | $ 52.9 |  | $ 52.9 |  |  | $ 52.4 |
Maximum Restricted Core Element Allowed in Tier One Capital, Percent |  |  |  |  |  |  |  |  |  |  | 25.00% |  |  |  |
Maximum Level of Consolidated Aggregate Assets Allowing for Inclusion of Trust Preferred Securities in Tier One Capital (in Dollars) |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000.0
Preferred Securities of Subsidiary Trust (in Dollars) |  |  |  |  |  |  |  |  | $ 52.9 |  | $ 52.9 |  |  | $ 52.4 |
Common Stock, Dividends, Per Share, Cash Paid |  |  | $ 0.15 |  | $ 0.14 |  | $ 0.14 |  | $ 0.15 | $ 0.12 | $ 0.43 | $ 2.36 |  |  |
Common Stock, Dividends, Per Share, Declared |  |  |  | $ 0.15 |  | $ 0.14 |  | $ 0.14 |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount (in Dollars) |  |  |  |  |  |  |  |  |  |  |  |  | $ 20.0 |  |
Scenario, Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Note 12 - Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Dividends, Per Share, Cash Paid | $ 0.15 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Repurchased Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Note 12 - Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Stock Repurchased During Period, Shares (in Shares) |  |  |  |  |  |  |  |  |  |  | 765,000 |  |  |  |
Share Price |  |  |  |  |  |  |  |  | $ 19.89 |  | $ 19.89 |  |  |  |
Stock Repurchased During Period, Value (in Dollars) |  |  |  |  |  |  |  |  |  |  | $ 15.2 |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Note 12 - Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Dividends, Per Share, Declared |  | $ 0.15 |  |  |  |  |  |  |  |  |  |  |  |  |

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