Note 9 - Goodwill and Intangible Assets (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Amortization of Intangible Assets, Total	$ 5,436	$ 5,567
Finite-Lived Intangible Assets, Amortization Expense, Remainder of Fiscal Year	9,700
Finite-Lived Intangible Assets, Amortization Expense, Year Two	15,400
Finite-Lived Intangible Assets, Amortization Expense, Year Three	12,400
Finite-Lived Intangible Assets, Amortization Expense, Year Four	8,300
Finite-Lived Intangible Assets, Amortization Expense, Year Five	4,800
Finite-Lived Intangible Assets, Amortization Expense, Year Six	2,900
Goodwill, Impairment Loss	0	0
Impairment of Intangible Assets, Indefinite-lived (Excluding Goodwill)	$ 0	$ 0