Note 7 - Stock-based Compensation - Stock-based Compensation Expense and Related Income Tax Benefit (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Stock-based compensation expense, gross	$ 3	$ 2	$ 7	$ 5
Income tax benefit at our statutory rate associated with stock-based compensation	(1)	(1)	(2)	(1)
Stock-based compensation expense, net	$ 2	$ 1	$ 5	$ 4

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

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-Publisher FASB
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