Note 6 - Accrued Expenses - Schedule of Accrued Expenses (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Project expenses	$ 3,827	$ 10,038
Compensation and benefits	1,426	1,556
Other	391	96
Total accrued expenses	$ 5,644	$ 11,690

Amount of accrued project expenses classified as current.

No definition available.

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Data Type:	xbrli:monetaryItemType
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- Definition

Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.20)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

+ References

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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- Definition

Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	instant