Note 6 - Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Accrued employee benefit plan costs	$ 8,726	$ 7,275
Stock based compensation	991	649
Net operating loss and tax credit carryforwards	448,624	215,797
Restructuring fees not currently deductible for tax purposes	0	566
Disallowed business interest expense carryforward	10,935	10,386
Capital loss carryforward	2,027	0
Other	2,656	3,152
Gross deferred tax assets	473,959	237,825
Less valuation allowance	(441,893)	(204,899)
Net deferred tax assets	32,066	32,926
Depreciation and amortization	(30,959)	(31,745)
Outside basis difference deferred tax liability	(2,891)	(2,891)
Foreign interest withholding tax	(1,072)	(990)
Other	692	572
Gross deferred tax liabilities	(34,230)	(35,054)
Net deferred tax assets (liabilities)	$ (2,164)	$ (2,128)