Note 13 - Income Taxes - Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2022	Dec. 31, 2021
Deferred tax assets
Net operating loss carryforwards and credits	$ 36,835	$ 25,742
Employee compensation	1,113	570
Share-based compensation expense	1,066	2,053
Development costs	964	0
Property, plant and equipment	749	753
Operating lease liabilities	187	125
Other	36	55
Less: valuation allowance	(36,642)	(26,378)
Total deferred tax assets	4,308	2,920
Deferred tax liabilities
Operating lease right-of-use assets	(4,308)	(2,920)
Total deferred tax liabilities	(4,308)	(2,920)
Net deferred tax assets (liabilities)	$ 0	$ 0