The percentage of specified real property securing the loan that the debt must not exceed according to covenant.

No definition available.

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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

Represents the amount required during the next 12 months for prepayment from excess cash flow generated during the current fiscal year.

+ References

No definition available.

+ Details

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- Definition

Represents the amount of interest expense recorded during the period from debt and finance leases, net of amounts capitalized.

+ References

No definition available.

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- Definition

The maximum senior leverage ratio.

+ References

No definition available.

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Data Type:	xbrli:pureItemType
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- Definition

The minimum fixed charge coverage ratio.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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Data Type:	num:percentItemType
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- Definition

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

Amount of the required periodic payments including both interest and principal payments.

+ References

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

Amount of interest capitalized during the period.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 20
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-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391

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Data Type:	xbrli:monetaryItemType
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Period Type:	duration

- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- 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.

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+ Details

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Balance Type:	credit
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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

+ Details

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- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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- Definition

The fee, expressed as a percentage of the line of credit facility, for available but unused credit capacity under the credit facility.

+ References

No definition available.

+ 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
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Balance Type:	credit
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Note 8 - Line of Credit and Long-term Debt (Details Textual) $ in Thousands		12 Months Ended
	Oct. 25, 2018 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Mar. 31, 2020 USD ($)
Interest Expense, Debt and Finance Leases, Net of Amounts Capitalized		$ 900	$ 500	$ 600
Interest Costs Capitalized		100
Letters of Credit Outstanding, Amount		$ 1,600
Wells Fargo Bank, N.A. [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 74,000
Maximum Senior Leverage Ratio		3.00
Minimum Fixed Charge Coverage Ratio		1.10
Letters of Credit Outstanding, Amount		$ 1,600
Wells Fargo Bank, N.A. [Member] \| Term Loan [Member]
Debt Instrument, Face Amount					$ 15,900
Long-term Debt, Monthly Repayment of Principal		300
Long-term Debt, Total		$ 13,800
Debt Instrument, Covenant, Maximum Debt Percentage of Securing Property		60.00%
Debt Instrument, Covenant, Repayment Percentage of Excess Cash Flow		20.00%
Debt Instrument, Prepayment from Excess Cash Flow Generated, Amount Payable in Next 12 Months		$ 4,600
Wells Fargo Bank, N.A. [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member] \| Term Loan [Member]
Debt Instrument, Basis Spread on Variable Rate		2.00%
Wells Fargo Bank, N.A. [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member] \| Term Loan [Member]
Debt Instrument, Basis Spread on Variable Rate		2.50%
Wells Fargo Bank, N.A. [Member] \| Revolving Credit Facility [Member]
Long-term Line of Credit, Total		$ 0	$ 0
Line of Credit Facility, Remaining Borrowing Capacity		$ 53,000
Debt, Weighted Average Interest Rate		1.73%	3.43%
Wells Fargo Bank, N.A. [Member] \| Revolving Credit Facility [Member] \| Minimum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.25%
Wells Fargo Bank, N.A. [Member] \| Revolving Credit Facility [Member] \| Maximum [Member]
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage	0.375%
Wells Fargo Bank, N.A. [Member] \| Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate	1.50%
Wells Fargo Bank, N.A. [Member] \| Revolving Credit Facility [Member] \| London Interbank Offered Rate (LIBOR) [Member] \| Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate	2.00%