Note 1 - Description of Business and Summary of Significant Accounting Policies - Property and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Property and equipment, gross	$ 1,262	$ 1,186
Accumulated depreciation	(525)	(461)
Total property and equipment, net	737	725
Land [Member]
Property and equipment, gross	123	119
Building and Building Improvements [Member]
Property and equipment, gross	$ 305	291
Building and Building Improvements [Member] \| Minimum [Member]
Estimated Useful Lives (Year)	7 years
Building and Building Improvements [Member] \| Maximum [Member]
Estimated Useful Lives (Year)	40 years
Equipment [Member]
Property and equipment, gross	$ 834	$ 776
Equipment [Member] \| Minimum [Member]
Estimated Useful Lives (Year)	3 years
Equipment [Member] \| Maximum [Member]
Estimated Useful Lives (Year)	20 years

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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