Note 3 - Income Taxes - Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Provision at the U.S. federal statutory rate	21.00%	21.00%
State taxes, net of federal benefit	3.10%	(15.50%)
Foreign tax rate differential	0.40%	(30.20%)
Valuation allowance	(48.80%)	(1504.60%)
Chile outside basis differential	0.40%	34.40%
PPP Loan Forgiveness	0.00%	(484.60%)
Accrual to return	3.10%	(329.30%)
Research and development credit	5.90%	(144.90%)
State rate change	9.50%	(124.00%)
China deferred adjustment	0.00%	1006.00%
China enterprise tax	0.00%	0.00%
Share based compensation	3.30%	1590.30%
Other true up	0.00%	0.00%
Intangible assets impairment and other non-deductibles	0.00%	0.00%
Other	(1.80%)	2.00%
Income tax (expense) benefit effective rate	(3.90%)	20.60%

Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to accrual to return.

No definition available.