Note 12 - Income Taxes - Reconciliation of Income Tax Expense (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2021	Mar. 31, 2020
Income tax expense	$ 15	$ 18
Effective income tax rate	28.00%	25.00%

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Name:	us-gaap_IncomeTaxExpenseBenefit
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration