Note 4 - Stock-based Compensation - Stock-based Compensation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Stock options	$ 14	$ 15	$ 15
Retention awards	68	66	58
Total stock-based compensation, before tax	99	88	73
Excess income tax benefits from equity compensation plans	21	26	55
Employee Stock [Member]
ESPP	$ 17	$ 7	$ 0

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