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Note 1 - Significant Accounting Policies (Details Textual) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2016 USD ($) shares | Jun. 30, 2015 shares | Jun. 30, 2016 USD ($) shares | Jun. 30, 2015 shares | Dec. 31, 2015 USD ($)
Restricted Stock [Member] |  |  |  |  |
Incremental Common Shares Attributable to Participating Nonvested Shares with Non-forfeitable Dividend Rights | 150,000 | 100,000 | 150,000 | 100,000 |
Employee Stock Option [Member] |  |  |  |  |
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements | 92,000 | 108,000 | 92,000 | 108,000 |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 7,000 | 91,000 | 7,000 | 91,000 |
Mortgage Loans [Member] |  |  |  |  |
Servicing Asset | $ | $ 597.0 |  | $ 597.0 |  |
Core Deposits [Member] |  |  |  |  |
Acquired Finite-lived Intangible Assets, Weighted Average Useful Life |  |  | 10 years |  |
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, Mortgage | $ | $ 2.9 |  | $ 2.9 |  | $ 1.3

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- Definition Number of days past due when interest income on commercial and mortgage loans is discontinued unless the loans are well-secured and in process of collection. + References No definition available. + Details
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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Antidilution -URI http://asc.fasb.org/extlink&oid=6505113 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Diluted Earnings Per Share -URI http://asc.fasb.org/extlink&oid=6510752 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Contingent Stock Agreement -URI http://asc.fasb.org/extlink&oid=6508534 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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- Definition This element represents nonvested share-based payment awards that contain non-forfeitable rights to dividends or dividend equivalents (whether paid or unpaid). Basic and dilutive earnings per share are generally disclosed for such shares using the two-class method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 61A -URI http://asc.fasb.org/extlink&oid=64863997&loc=SL5780137-109256 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Participating Security -URI http://asc.fasb.org/extlink&oid=6519812 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60A -URI http://asc.fasb.org/extlink&oid=64863997&loc=SL5780132-109256 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 59A -URI http://asc.fasb.org/extlink&oid=64863997&loc=SL5780131-109256 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 60B -URI http://asc.fasb.org/extlink&oid=64863997&loc=SL5780133-109256 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 68B -URI http://asc.fasb.org/extlink&oid=64863997&loc=SL5498026-109256 + Details
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 28A -URI http://asc.fasb.org/extlink&oid=64863997&loc=d3e1500-109256 + Details
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- Definition Amount, after allowance for bad debt, of mortgage loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=65884687&loc=d3e4428-111522 + Details
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