Note 3 - Income Taxes - Provision for Income Taxes (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Provision for income taxes (Note 3)	$ (35)	$ (34)	$ (178)	$ (380)
Effective tax rate	16.10%	13.10%	20.80%	21.20%