Note 4 - Restructuring of Operations (Details Textual) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Restructuring Charges, Total	$ 34	$ 29	$ 25
Restructuring Reserve, Accrual Adjustment	$ (2)	$ (2)	$ (7)
Restructuring and Related Cost, Expected Number of Positions Eliminated	500

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

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