Requirement for cash and certain cash equivalents under the debt agreement.

No definition available.

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Requirement for the minimum EBITDA for the fourth quarter of 2020 under the debt agreement.

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No definition available.

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Requirement for the minimum EBITDA for the first quarter of 2021 under the debt agreement.

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No definition available.

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Requirement for the minimum EBITDA for the second quarter of 2021 under the debt agreement.

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No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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No definition available.

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- Definition

Amount of assets pledged to secure a debt instrument.

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The average effective interest rate during the reporting period.

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

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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No definition available.

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Weighted average interest rate of debt outstanding.

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

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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Note 11 - Debt and Other Financing Arrangements (Details Textual) - USD ($)														12 Months Ended			68 Months Ended
	Mar. 23, 2021	Nov. 02, 2020	May 01, 2020	Dec. 04, 2019	Dec. 02, 2019	Nov. 10, 2017	Oct. 30, 2017	Mar. 23, 2016	Sep. 15, 2015	Aug. 08, 2014	Jun. 13, 2014	May 22, 2014	Mar. 24, 2014	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 04, 2019
Interest Expense, Total														$ 75,000	$ 59,000	$ 106,000
Equipment Loan Arrangement [Member]
Debt Instrument, Interest Rate, Stated Percentage														3.79%
Proceeds from Issuance of Long-term Debt, Total															1,416,000
Equipment Loan Arrangement [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate														1.75%
Paycheck Protection Program CARES Act [Member]
Debt Instrument, Interest Rate, Stated Percentage														1.00%
Proceeds from Issuance of Long-term Debt, Total			$ 2,181,157											$ 2,181,000
Banc of America Leasing and Capital [Member] \| Equipment Loan Arrangement [Member] \| Line of Credit [Member]
Interest Expense, Total					$ 16,000,000									75,000
Debt Instrument, Term (Month)					5 years
Debt Instrument, Interest Rate, Stated Percentage					3.79%
Debt Instrument, Covenant, Cash and Certain Cash Equivalents, Minimum		$ 1,500,000
Debt Instrument, Covenant, Minimum EBITDA for Fourth Quarter of 2020		1
Debt Instrument, Covenant, Minimum EBITDA for First Quarter of 2021		225,000
Debt Instrument, Collateral Amount														3,100,000
Proceeds from Issuance of Long-term Debt, Total				$ 1,400,000		$ 2,100,000		$ 610,000	$ 1,100,000	$ 1,000,000	$ 3,000,000	$ 1,900,000	$ 1,100,000				$ 12,200,000
Repayments of Long-term Debt, Total														$ 700,000	$ 400,000
Debt Instrument, Interest Rate During Period														3.00%
Debt, Weighted Average Interest Rate														3.00%
Debt Instrument, Covenant, Minimum EBITDA for Second Quarter of 2021		$ 225,000
Banc of America Leasing and Capital [Member] \| Equipment Loan Arrangement [Member] \| Line of Credit [Member] \| Subsequent Event [Member]
Debt Instrument, Covenant, Minimum EBITDA for First Quarter of 2021	$ 1
Banc of America Leasing and Capital [Member] \| Equipment Loan Arrangement [Member] \| Line of Credit [Member] \| London Interbank Offered Rate (LIBOR) [Member]
Debt Instrument, Basis Spread on Variable Rate							1.75%