Note 13 - Income Taxes (Details Textual) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Feb. 21, 2020
Schedule Of Income Taxes [Line Items]
U.S. corporate income tax rate	21.00%	21.00%
Valuation Allowance of Deferred Tax Assets [Member]
Schedule Of Income Taxes [Line Items]
Provision associated with establishment of valuation allowance on deferred tax assets		$ 167
Foreign Tax Authority [Member]
Schedule Of Income Taxes [Line Items]
Liability for Uncertain Tax Positions, Current	$ 3
Unrecognized Tax Benefits Income Tax Penalties And Interest Accrued	$ 4
Domestic Tax Authority [Member] | IRS [Member]
Schedule Of Income Taxes [Line Items]
Liability for Uncertain Tax Positions, Current			$ 41