Note 5 - Leases (Details Textual) $ in Thousands	1 Months Ended	3 Months Ended	9 Months Ended
	Aug. 31, 2020 USD ($) ft²	Sep. 30, 2022 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Mar. 31, 2017 ft²
Short-term and Variable Lease, Cost			$ 300
Lease, Cost, Total			1,400	$ 1,100
Operating Lease, Payments			$ 2,200	$ 1,800
Operating Lease, Weighted Average Remaining Lease Term (Year)		2 years 2 months 12 days	2 years 2 months 12 days
Operating Lease, Weighted Average Discount Rate, Percent		7.63%	7.63%
Sublease Income		$ 700	$ 2,100
Proceeds from Lease Payment, Operating Activity		$ 700	$ 2,100
The 1020 Marsh Road Facility [Member]
Area of Real Estate Property (Square Foot) | ft²					34,500
Lessee, Operating Lease, Term of Contract (Month)					87 months
Lessee, Operating Lease, Number of Renewal Options					1
Lessee, Operating Lease, Renewal Term (Year)					5 years
Office Space in North Carolina [Member]
Area of Real Estate Property (Square Foot) | ft²	4,128
Lessee, Operating Lease, Term of Contract (Month)	63 months
Lessee, Operating Lease, Monthly Payments	$ 9
Lessee, Operating Lease, Abatement Term (Month)	3 months