Note 8 - Notes Payable and Convertible Notes Payable - Long-term Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Future debt payments, net	$ 16,927	$ 16,915
Less notes payable, current portion, net of unamortized discount and debt issuance costs	(14,987)	(14,627)
Notes payable, net of current portion	1,820	1,894
Notes payable	16,927	16,915
Convertible notes payable, net of current portion	5,265	5,258
Notes Payable [Member]
Less unamortized discount and debt issuance costs	(120)	(394)
Less notes payable, current portion, net of unamortized discount and debt issuance costs	(14,987)	(14,627)
Notes payable, net of current portion	1,820	1,894
Convertible Notes Payable [Member]
Future debt payments, net	10,388	10,308
Notes payable	10,388	10,308
Less unamortized discount and debt issuance costs	(81)	(174)
Less convertible notes payable, current portion, net of unamortized discount and debt issuance costs	(5,042)	(4,876)
Convertible notes payable, net of current portion	$ 5,265	5,258
The 2019 Cecil Loan [Member] \| Notes Payable [Member]
Interest Rate	8.00%
Future debt payments, net	$ 140	138
Notes payable	$ 140	138
The 2019 Maryland DHCD [Member] \| Notes Payable [Member]
Interest Rate	8.00%
Future debt payments, net	$ 704	694
Notes payable	$ 704	694
The 2022 Maryland DHCD [Member] \| Notes Payable [Member]
Interest Rate	6.00%
Future debt payments, net	$ 1,083	1,083
Notes payable	$ 1,083	1,083
Avenue [Member] \| Notes Payable [Member]
Interest Rate	15.10%
Future debt payments, net	$ 15,000	15,000
Notes payable	$ 15,000	15,000
Avenue [Member] \| Convertible Notes Payable [Member]
Interest Rate	15.10%
Future debt payments, net	$ 5,000	5,000
Notes payable	5,000	5,000
The 2022 DHCD Loan [Member] \| Notes Payable [Member]
Future debt payments, net	5,341
Notes payable	$ 5,341
The 2022 DHCD Loan [Member] \| Convertible Notes Payable [Member]
Interest Rate	6.00%
Future debt payments, net	$ 5,388	5,308
Notes payable	$ 5,388	$ 5,308

Amount of convertible note payable as of the balance sheet date, classified as noncurrent.

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Carrying value as of the balance sheet date of the portion of long-term debt due within one year or the operating cycle if longer identified as Convertible Notes Payable. Convertible Notes Payable is a written promise to pay a note which can be exchanged for a specified amount of another, related security, at the option of the issuer and the holder.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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Amount, after accumulated amortization, of debt discount (premium).

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Carrying value as of the balance sheet date of notes payable (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion.

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Sum of the carrying values as of the balance sheet date of the portions of long-term notes payable due within one year or the operating cycle if longer.

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