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Note 5 - Line of Credit and Long-term Debt (Details Textual) - Wells Fargo Bank, N.A. [Member] - USD ($) $ in Thousands |  | 9 Months Ended |  |
--- | --- | --- | --- | ---
Oct. 25, 2018 | Sep. 30, 2020 | Mar. 31, 2020 | Dec. 31, 2019
Line of Credit Facility, Maximum Borrowing Capacity | $ 74,000 |  |  |
Maximum Senior Leverage Ratio |  | 3.00 |  |
Minimum Fixed Charge Coverage Ratio |  | 1.10 |  |
Term Loan [Member] |  |  |  |
Debt Instrument, Face Amount |  |  | $ 15,900 |
Long-term Debt, Monthly Repayment of Principal |  | $ 300 |  |
Long-term Debt, Total |  | $ 14,600 |  |
Debt Instrument, Covenant, Maximum Debt Percentage of Securing Property |  | 60.00% |  |
Debt Instrument, Covenant, Repayment Percentage of Excess Cash Flow |  | 20.00% |  |
London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] | Term Loan [Member] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 2.00% |  |
London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] | Term Loan [Member] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate |  | 2.50% |  |
Revolving Credit Facility [Member] |  |  |  |
Long-term Line of Credit, Total |  | $ 0 |  | $ 0
Line of Credit Facility, Remaining Borrowing Capacity |  | $ 54,800 |  |
Debt, Weighted Average Interest Rate |  | 1.74% |  | 3.43%
Revolving Credit Facility [Member] | Minimum [Member] |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.25% |  |  |
Revolving Credit Facility [Member] | Maximum [Member] |  |  |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage | 0.375% |  |  |
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Minimum [Member] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 1.50% |  |  |
Revolving Credit Facility [Member] | London Interbank Offered Rate (LIBOR) [Member] | Maximum [Member] |  |  |  |
Debt Instrument, Basis Spread on Variable Rate | 2.00% |  |  |

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- Definition The percentage of specified real property securing the loan that the debt must not exceed according to covenant. + References No definition available. + Details
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- Definition The percentage of excess cash flow that repayment may be required under debt instrument covenant + References No definition available. + Details
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- Definition Face (par) amount of debt instrument at time of issuance. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=119993939&loc=d3e28551-108399 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 + Details
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- Definition 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. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(b),22(b)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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- Definition Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 470 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=120520924&loc=SL6031897-161870 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(16)) -URI http://asc.fasb.org/extlink&oid=120400017&loc=d3e572229-122910 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(16)) -URI http://asc.fasb.org/extlink&oid=120398452&loc=d3e534808-122878 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(22)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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