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Note 20 - Regulatory Capital Matters (Details Textual) - USD ($) |  | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2017 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015 | Jan. 01, 2016
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets Rule 1 |  |  |  |  | 0.625%
Increase in Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets |  |  |  |  | 0.625%
Tier 1 Capital Conservation Buffer of Risk Weighted Assets |  |  |  |  | 2.50%
Cash Dividends Paid to Parent Company by Consolidated Subsidiaries |  | $ 8,725,000 | $ 9,100,000 | $ 10,000,000 |
Series A Preferred Stock [Member] |  |  |  |  |
Stock Redeemed or Called During Period, Shares | 9,360 | 9,360 | 8,661 | 9,979 |

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- Definition The increase in 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 as per Basel III framework. + References No definition available. + Details
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- Definition Tier 1 Capital conversion buffer of risk weighted assets as per Basel III framework. + References No definition available. + Details
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- Definition The new 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 as per Basel III framework. + References No definition available. + Details
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- Definition This element represents disclosure of the aggregate cash dividends paid to the entity by consolidated subsidiaries. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 3 -Subparagraph (SX 210.12-04.(b)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e24072-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 235 -Section S99 -Paragraph 2 -Subparagraph (SX 210.9-06) -URI http://asc.fasb.org/extlink&oid=6882215&loc=d3e537971-122884 + Details
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- Definition Number of stock bought back by the entity at the exercise price or redemption price. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21463-112644 + Details
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