Note 3 - Stock-based Compensation - Stock-based Compensation Plan Expenses (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2021	Mar. 31, 2020
Share based compensation expense		$ 28,583	$ 18,562
Tax benefit related to stock-based compensation	[1]	430	470
Cost of Sales [Member]
Share based compensation expense		816	557
Research and Development Expense [Member]
Share based compensation expense		6,165	4,370
Selling, General and Administrative Expenses [Member]
Share based compensation expense		$ 21,602	$ 13,635

[1] Amount reflects the tax benefit related to stock-based compensation recorded for equity awards that are expected to generate tax deductions when they vest in future periods.