Note 4 - Balance Sheet Components (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022	Dec. 31, 2021
Cash, Cash Equivalents, Restricted Cash, and Restricted Cash Equivalents	$ 33,238,000	$ 50,768,000	$ 33,238,000	$ 50,768,000	$ 46,013,000	$ 143,745,000
Restricted Cash	79,000		79,000		2,000,000
Depreciation	1,000,000	500,000	2,800,000	1,300,000
Tangible Asset Impairment Charges			0	0
Operating Lease, Right-of-Use Asset	25,753,000		25,753,000		25,715,000
Amortization of Intangible Assets	200,000	$ 300,000	500,000	$ 1,000,000
Goodwill	$ 4,508,000		4,508,000		$ 4,508,000
Goodwill, Impairment Loss			$ 0
Developed Technology Rights [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	11 years 9 months		11 years 9 months
Finite-Lived Intangible Asset, Remaining Life (Year)			6 years 1 month 6 days
Intellectual Property [Member]
Finite-Lived Intangible Asset, Useful Life (Year)	20 years		20 years
Finite-Lived Intangible Asset, Remaining Life (Year)			4 years 3 months