Note 10 - Income Taxes Unrecognized Tax Benefits (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Contingency [Line Items]
Unrecognized Tax Benefits that Would Impact Effective Tax Rate		$ 17,800
Unrecognized Tax Benefits, Interest and Penalties Charged to Income		1,300	$ (61,600)	$ 2,200
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at beginning of period	$ 37,208	33,552	123,951
Tax positions related to the current year [Abstract]
Unrecognized Tax Benefits, Increases Resulting from Current Period Tax Positions		3,215	5,058
Tax positions related to prior years [Abstract]
Unrecognized Tax Benefits, Increases Resulting from Prior Period Tax Positions		441	26,465
Unrecognized Tax Benefits, Decreases Resulting from Prior Period Tax Positions		0	(43,146)
Unrecognized Tax Benefits, Decrease Resulting from Settlements with Taxing Authorities		0	(52,353)
Unrecognized Tax Benefits, Reductions Resulting from Lapse of Applicable Statute of Limitations		0	(26,423)
Balance at end of period		37,208	$ 33,552	$ 123,951
Unrecognized Tax Benefits, Period Increase (Decrease)		$ 3,700
Scenario, Forecast
Tax positions related to prior years [Abstract]
Unrecognized Tax Benefits, Reductions Resulting from Lapse of Applicable Statute of Limitations	$ (7,500)