Note 16 - Related Party Transactions (Details Textual) - BSLF, L.L.C. [Member] - Funding Agreement [Member] - USD ($)	1 Months Ended	12 Months Ended
Mar. 29, 2022	Dec. 31, 2021
Percentage of Remaining Litigation Proceeds Up to Three Times the Actual Funding Amount		50.00%
Percentage of Remaining Litigation Proceeds		30.00%
Increase (Decrease) in Accounts Payable, Related Parties		$ (523,000)
Due from Related Parties, Total		562,000
Selling, General and Administrative Expenses [Member]
Legal Fees		195,000
Accrued Expenses and Other Current Liabilities [Member]
Accounts Payable, Related Parties		$ 156,000
Subsequent Event [Member]
Legal Fees	$ 688,000
Maximum Discount on Legal Service	$ 300,000

Maximum discount on legal service.

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Represents the percentage of the remaining Litigation Proceeds to be added to any taxes paid by or imposed with request to claims and an amount, without reduction, set-off or counterclaim, equal to the amount actually paid pursuant to the agreement.

+ References

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Represents the percentage of the remaining Litigation Proceeds, up to three times the Actual Funding Amount, to be added to any taxes paid by or imposed with request to claims and an amount, without reduction, set-off or counterclaim, equal to the amount actually paid pursuant to the agreement.

+ References

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Amount for accounts payable to related parties.

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For an unclassified balance sheet, amounts due from related parties including affiliates, employees, joint ventures, officers and stockholders, immediate families thereof, and pension funds.

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The increase (decrease) during the reporting period in the obligations due for goods and services provided by the following types of related parties: a parent company and its subsidiaries, subsidiaries of a common parent, an entity and trust for the benefit of employees, such as pension and profit-sharing trusts that are managed by or under the trusteeship of the entities' management, an entity and its principal owners, management, or member of their immediate families, affiliates, or other parties with the ability to exert significant influence.

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The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

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