Note 4 - Restructuring of Operations (Details Textual) $ in Millions	3 Months Ended
Mar. 31, 2021 USD ($)	Mar. 31, 2020 USD ($)
Restructuring Charges, Total	$ 1	$ 3
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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Period Type:	duration