Note 8 - Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Amortization of Intangible Assets, Total	$ 22,112	$ 28,861	$ 32,953
Finite-Lived Intangible Assets, Amortization Expense, Next Twelve Months	21,542
Finite-Lived Intangible Assets, Amortization Expense, Year Two	21,451
Finite-Lived Intangible Assets, Amortization Expense, Year Three	19,653
Finite-Lived Intangible Assets, Amortization Expense, Year Four	12,339
Finite-Lived Intangible Assets, Amortization Expense, Year Five	$ 9,975