Note 4 - Balance Sheet Components (Details Textual) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Accounts Receivable, after Allowance for Credit Loss, Current	$ 556		$ 3,008
Accounts Receivable, Allowance for Credit Loss, Current	0		0
Depreciation	900	$ 900
Tangible Asset Impairment Charges, Total	0	0
Operating Lease, Right-of-Use Asset	23,753		24,840
Amortization of Intangible Assets	200	$ 200
Goodwill	4,508		4,508
Goodwill, Impairment Loss	$ 0
Intellectual Property [Member] | Minimum [Member]
Finite-Lived Intangible Asset, Remaining Life (Year)	5 years 7 months 6 days
Intellectual Property [Member] | Maximum [Member]
Finite-Lived Intangible Asset, Remaining Life (Year)	3 years 9 months
Facility in Burlingame, California [Member]
Operating Lease, Right-of-Use Asset			3,100
Royalty [Member]
Accounts Receivable, after Allowance for Credit Loss, Current	$ 600		$ 3,000