Note 7 - Income Taxes - Components of Income Tax Expense (Benefit) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Netherlands (2020 and 2019: U.K.)	$ 216	$ (707)	$ 0
Foreign	16,777	17,883	17,160
Total current tax	16,993	17,176	17,160
Netherlands (2020 and 2019: U.K.)	0	0	0
Foreign	(726)	(20,576)	(18,297)
Total deferred tax	(726)	(20,576)	(18,297)
Income tax expense (benefit)	$ 16,267	$ (3,400)	$ (1,137)

Amount of current federal tax expense (benefit) pertaining to income (loss) from continuing operations.

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