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Note 1 - Significant Accounting Policies (Details Textual) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2019 USD ($) shares | Jun. 30, 2018 shares | Jun. 30, 2019 USD ($) shares | Jun. 30, 2018 shares | Jan. 01, 2019 USD ($) | Dec. 31, 2018 USD ($)
Number of Unconsolidated Business Trusts Formed to Issue Trust Preferred Securities | 5 |  | 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, Ending Balance | $ 4.5 |  | $ 4.5 |  |  | $ 1.1
Servicing Asset, Total | $ 629.0 |  | $ 629.0 |  |  |
Accounting Standards Update 2016-02 [Member] |  |  |  |  |  |
Operating Lease, Right-of-Use Asset |  |  |  |  | $ 1.3 |
Operating Lease, Liability, Total |  |  |  |  | $ 1.3 |
Core Deposits [Member] |  |  |  |  |  |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life |  |  | 10 years |  |  |
Restricted Stock [Member] |  |  |  |  |  |
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights | shares | 261,000 | 234,000 | 261,000 | 234,000 |  |
Share-based Payment Arrangement, Option [Member] |  |  |  |  |  |
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights | shares | 10,000 | 17,000 | 10,000 | 17,000 |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | shares | 7,000 | 7,000 | 7,000 | 7,000 |  |

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