Exercise price per share or per unit of warrants or rights outstanding.

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The price per share of the conversion feature embedded in the debt instrument.

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Face (par) amount of debt instrument at time of issuance.

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Amount of the cost of borrowed funds accounted for as interest expense for debt.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount; classified as operating and investing activities.

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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The cash outflow from the repayment of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

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Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Note 4 - Debt Obligations (Details Textual) - USD ($)		3 Months Ended
Note 4 - Debt Obligations (Details Textual) - USD ($)	Mar. 01, 2021	Mar. 31, 2021	Mar. 31, 2020	Dec. 31, 2020
Interest Expense, Debt, Total		$ 93,000	$ 757,000
Long-term Line of Credit, Total				$ 50,000
Warrants Issued in Connection with Conversion of Interest on Note Payable Maturing March 8, 2023 [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)	225,000
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)	$ 0.16
Warrants and Rights Outstanding, Term (Month)	5 years
Convertible Note, Maturing August 9, 2021 [Member]
Repayments of Convertible Debt	$ 600,000
Interest Paid, Including Capitalized Interest, Operating and Investing Activities, Total	7,000
Line of Credit, Maturing September 1, 2019 [Member]
Interest Paid, Including Capitalized Interest, Operating and Investing Activities, Total	1,000
Repayments of Long-term Lines of Credit	50,000
Long-term Line of Credit, Total		$ 0
Note Payable, Maturing March 8, 2023 [Member]
Debt Instrument, Face Amount	$ 50,000
Debt Instrument, Convertible, Conversion Price (in dollars per share)	$ 0.16