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Note 12 - Regulatory Matters (Details Textual) - USD ($) $ / shares in Units, $ in Millions |  |  |  |  |  |  | 3 Months Ended | 6 Months Ended | 41 Months Ended |  |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 19, 2018 | Jul. 12, 2018 | Jun. 20, 2018 | Apr. 12, 2018 | Mar. 21, 2018 | Jan. 11, 2018 | Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jan. 01, 2019 | Dec. 31, 2017 | Apr. 19, 2016 | Jan. 30, 2015 | Dec. 31, 2009
Preferred Securities of Subsidiary Trust |  |  |  |  |  |  | $ 43.8 |  | $ 43.8 |  | $ 43.8 |  | $ 43.4 |  |  |
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 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15,000.0
Trust Preferred Securities Included in Tier One Capital |  |  |  |  |  |  | $ 43.8 |  | $ 43.8 |  | $ 43.8 |  | $ 43.4 |  |  |
Capital Conservation Buffer |  |  |  |  |  |  | 2.50% |  | 2.50% |  | 2.50% |  |  |  |  |
Common Stock, Dividends, Per Share, Declared |  |  |  | $ 0.22 |  | $ 0.22 |  |  |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 20.0 |
Stock Repurchase Program Additional Authorized Amount |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 15.0 |  |
Stock Repurchased During Period, Shares |  |  |  |  |  |  |  |  | 0 |  | 956,419 |  |  |  |  |
Stock Repurchased During Period, Value |  |  |  |  |  |  |  |  |  |  | $ 19.5 |  |  |  |  |
Treasury Stock Acquired, Average Cost Per Share |  |  |  |  |  |  |  |  |  |  | $ 20.38 |  |  |  |  |
Common Stock, Dividends, Per Share, Cash Paid |  |  | $ 0.22 |  | $ 0.22 |  | $ 0.22 | $ 0.18 | $ 0.44 | $ 0.36 |  |  |  |  |  |
Subsequent Event [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Stock, Dividends, Per Share, Declared |  | $ 0.24 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Scenario, Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Common Equity Tier 1 Risk Based Capital Required For Capital Adequacy to Risk Weighted Assets |  |  |  |  |  |  |  |  |  |  |  | 7.00% |  |  |  |
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets |  |  |  |  |  |  |  |  |  |  |  | 8.50% |  |  |  |
Capital Required for Capital Adequacy to Risk Weighted Assets |  |  |  |  |  |  |  |  |  |  |  | 10.50% |  |  |  |
Common Stock, Dividends, Per Share, Cash Paid | $ 0.24 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |

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- Definition An additional amount held in risk-based capital designed to ensure that banks build up capital buffers outside periods of stress which can be drawn down as losses are incurred. The requirement is based on simple capital conservation rules designed to avoid breaches of minimum capital requirements. + References No definition available. + Details
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- Definition The minimum common equity tier one capital ratio (common equity tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References No definition available. + Details
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- Definition The maximum level of consolidated aggregate assets allowing for inclusion of trust preferred securities in Tier 1 Capital under the Dodd-Frank Act. + References No definition available. + Details
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- Definition Trust preferred securities possesses characteristics of both equity and debt issues and are generally issued by bank holding companies. + References No definition available. + Details
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- Definition Trust preferred securities held by the trust that are included in Tier One Capital and subject to certain limitations. + References No definition available. + Details
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- Definition The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21463-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(29)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(28)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958570-112826 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=84167132&loc=SL5958568-112826 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 505 -Section 50 -Paragraph 1H -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=84167132&loc=d3e65071-112826 + Details
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