Note 8 - Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	24.40%	25.10%
Unrecognized Tax Benefits, Ending Balance	$ 81.6
Unrecognized Tax Benefits that Would Impact Effective Tax Rate	69.6
Unrecognized Tax Benefits, Income Tax Penalties and Interest Accrued, Total	$ 7.1