Note 6 - Intangible Assets - Amortization (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Amortization of intangible assets	$ 69,565	$ 62,492	$ 57,224
Cost of Sales [Member]
Amortization of intangible assets	36,987	32,845	28,502
Research and Development Expense [Member]
Amortization of intangible assets	22,305	19,311	18,352
Selling and Marketing Expense [Member]
Amortization of intangible assets	9,728	9,727	9,727
General and Administrative Expense [Member]
Amortization of intangible assets	$ 545	$ 609	$ 643