Note 4 - Stock Options and Other Stock Plans - Stock-based Compensation (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Stock options	$ 16	$ 14	$ 15
Retention awards	71	68	66
Total stock-based compensation expense, before tax	107	99	88
Excess income tax benefits from equity compensation plans	11	21	26
Employee Stock [Member]
ESPP	$ 20	$ 17	$ 7

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Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Amount of noncash expense for award of restricted stock or unit under share-based payment arrangement.

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