Note 4 - Stock-based Compensation - Stock-based Compensation (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Stock options	$ 3	$ 4	$ 7	$ 8
Retention awards	19	18	41	34
Total stock-based compensation, before tax	26	22	56	42
Excess tax benefits from equity compensation plans	1	2	18	17
Employee Stock [Member]
ESPP	$ 4	$ 0	$ 8	$ 0

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

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