Amount of amortization expense attributable to debt issuance costs.

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The amount of debt issuance costs that were incurred during a noncash or partial noncash transaction.

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Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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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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Amount of the fee for available but unused credit capacity under the credit facility.

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The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Note 7 - Notes Payable (Details Textual) - USD ($) $ in Thousands			3 Months Ended	12 Months Ended
	Oct. 22, 2018	Oct. 21, 2018	Mar. 31, 2020	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Amortization of Debt Issuance Costs				$ 502	$ 452	$ 476
New Credit Facility [Member]
Debt Issuance Costs, Gross			$ 2,300
Debt Issuance Costs Incurred During Noncash or Partial Noncash Transaction			$ 212
Amortization of Debt Issuance Costs				$ 502	452	476
Line of Credit Facility, Commitment Fee Percentage	0.38%	0.50%		0.50%
Line of Credit Facility, Commitment Fee Amount				$ 23	19	$ 24
Previous Credit Facility [Member]
Line of Credit Facility, Maximum Borrowing Capacity				5,000
Long-term Line of Credit, Total				$ 0	$ 0