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Note 20 - Subsequent Events (Details Textual) - USD ($) $ / shares in Units, $ in Millions |  |  | 9 Months Ended | 12 Months Ended | 33 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Nov. 07, 2018 | Oct. 25, 2018 | Sep. 30, 2018 | Dec. 31, 2017 | Oct. 25, 2018 | Nov. 08, 2018 | Oct. 26, 2018 | Feb. 01, 2016
Treasury Stock, Shares, Acquired |  |  | 0 | 0 |  |  |  |
February 2016 Repurchase Program [Member] |  |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  |  | $ 45.0
Stock Repurchase Program, Remaining Authorized Repurchase Amount |  |  | $ 7.5 | $ 7.5 |  |  |  |
February 2016 Repurchase Program [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Treasury Stock, Shares, Acquired |  | 200,326 |  |  | 1,580,904 |  |  |
Treasury Stock, Value, Acquired, Cost Method |  | $ 7.5 |  |  |  |  |  |
Treasury Stock Acquired, Average Cost Per Share |  |  |  |  | $ 28.46 |  |  |
October 2018 Repurchase Program [Member] | Subsequent Event [Member] |  |  |  |  |  |  |  |
Treasury Stock, Shares, Acquired | 255,000 |  |  |  |  |  |  |
Treasury Stock, Value, Acquired, Cost Method | $ 9.7 |  |  |  |  |  |  |
Stock Repurchase Program, Authorized Amount |  |  |  |  |  |  | $ 45.0 |
Treasury Stock Acquired, Average Cost Per Share | $ 38.26 |  |  |  |  |  |  |
Stock Repurchase Program, Remaining Authorized Repurchase Amount |  |  |  |  |  | $ 35.3 |  |

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- Definition Amount of stock repurchase plan authorized. + References No definition available. + Details
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- Definition Total cost of shares repurchased divided by the total number of shares repurchased. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6405813&loc=d3e23239-112655 + Details
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