Note 8 - Notes Payable and Convertible Notes Payable - Schedule of Future Payments (Details) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Future debt payments, net	$ 16,915	$ 16,488
Notes Payable [Member] \| The 2019 MD Loan [Member]
2024	0
2025	0
2026	0
2027	0
2028	0
Thereafter	500
Total debt principal payments	500
Accrued and unpaid interest	194
Less unamortized discount and debt issuance costs	0
Future debt payments, net	694
Notes Payable [Member] \| The 2019 Cecil Loan [Member]
2024	0
2025	0
2026	0
2027	0
2028	0
Thereafter	100
Total debt principal payments	100
Accrued and unpaid interest	38
Less unamortized discount and debt issuance costs	0
Future debt payments, net	138	$ 130
Notes Payable [Member] \| The 2021 Avenue Loan [Member]
2024	20,000
2025	0
2026	0
2027	0
2028	0
Thereafter	0
Total debt principal payments	20,000
Accrued and unpaid interest	0
Less unamortized discount and debt issuance costs	(497)
Future debt payments, net	19,503
Notes Payable [Member] \| The 2022 MD Loan [Member]
2024	0
2025	347
2026	369
2027	317
2028	0
Thereafter	0
Total debt principal payments	1,033
Accrued and unpaid interest	50
Less unamortized discount and debt issuance costs	(21)
Future debt payments, net	1,062
Notes Payable [Member] \| The 2022 DHCD Loan [Member]
2024	0
2025	0
2026	0
2027	0
2028	5,000
Thereafter	0
Total debt principal payments	5,000
Accrued and unpaid interest	308
Less unamortized discount and debt issuance costs	(50)
Future debt payments, net	$ 5,258

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