Note 19 - Stock Repurchase Program (Details Textual) - February 2016 Repurchase Program [Member] - USD ($) $ / shares in Units, $ in Millions	Feb. 01, 2016	Mar. 31, 2018	Dec. 31, 2017
Stock Repurchase Program, Number of Shares Authorized to be Repurchased	45,000,000
Treasury Stock, Shares, Acquired	1,380,578
Treasury Stock, Value, Acquired, Cost Method	$ 37.5
Treasury Stock Acquired, Average Cost Per Share	$ 27.13
Stock Repurchase Program, Remaining Number of Shares Authorized to be Repurchased		7,500,000	7,500,000