Note 10 - Income Taxes Income Tax Provision (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Income Tax Disclosure [Abstract]
Current provision (benefit)	$ 19,522	$ (42,398)	$ 59,122
Deferred provision (benefit)	157,162	120,573	166,527
Total income tax provision (benefit)	$ 176,684	$ 78,175	$ 225,649