Note 11 - Income Tax (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Deferred tax assets:
Federal net operating loss carryforward	$ 39,340	$ 36,803
Stock based compensation and other items	4,779	0
Intellectual property	58,504	58,504
Accrued expense	0	1,262
Patent amortization	4	4
Deferred tax assets before valuation	102,627	96,573
Valuation allowance	(102,627)	(96,573)
Net deferred income tax assets	$ 0	$ 0