Note 3 - Financing Arrangements - Outstanding Borrowings (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Senior notes	$ 945,257	$ 1,305,424
Less current portion of long-term debt	(355,972)	0
Senior Notes [Member]
Senior notes	1,301,200	1,305,400
Less current portion of long-term debt	(356,000)	0
Long-term Debt, Total	$ 945,200	$ 1,305,400