Note 3 - Income Taxes - Income Tax Rate Reconciliation (Details)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Provision at the U.S. federal statutory rate	21.00%	21.00%
State taxes, net of federal benefit	4.70%	3.10%
Foreign tax rate differential	(0.60%)	0.40%
Valuation allowance	(4.90%)	(48.80%)
Chile outside basis differential	0.00%	0.40%
Italy IRES/IREP	(3.80%)	0.00%
Accrual to return	(5.80%)	3.10%
Research and development credit	5.40%	5.90%
State rate change	(1.40%)	9.50%
Share based compensation	(6.70%)	3.30%
Other Deferred true up	(6.60%)	0.00%
Global Intangible Low-Taxed Income (GILTI) inclusion	(4.40%)	0.00%
Other	(1.70%)	(1.80%)
Income tax (expense) benefit effective rate	(4.80%)	(3.90%)