Note 7 - Leases (Details Textual) $ in Thousands	Sep. 30, 2023 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2021 USD ($)
Operating Lease, Right-of-Use Asset	$ 25,753	$ 25,715
Operating Lease, Weighted Average Discount Rate, Percent	9.80%
Operating Lease, Weighted Average Remaining Lease Term (Year)	5 years 4 months 24 days
Lessee, Operating Lease, Lease Not yet Commenced, Future Payment Obligation	$ 200
Right of Use for Equipment with Initial Terms Exceeding One Year [Member]
Lessee, Operating Lease, Number of Right-of-Use Leases	7
Lease Agreements for Manufacturing Equipment with Initial Terms of One Year or Less [Member]
Lessee, Short-term Lease, Number of Leases	1
Facility in Burlingame, California [Member]
Lessee, Short-term Lease, Number of Leases	2
Lease for Facility in South San Francisco Commenced in Third Quarter of 2022 [Member]
Operating Lease, Right-of-Use Asset			$ 15,000
Lease for Facility in South San Francisco Commenced in First Quarter of 2023 [Member]
Operating Lease, Right-of-Use Asset			$ 3,100