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Note 7 - Credit Agreement (Details Textual) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Oct. 22, 2021 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Interest Expense, Debt and Finance Leases, Net of Amounts Capitalized |  | $ 1,200 | $ 900 | $ 500
Interest Costs Capitalized |  | 100 | 100 |
Letters of Credit Outstanding, Amount |  | 1,600 |  |
Wells Fargo Bank, N.A. [Member] |  |  |  |
Line of Credit Facility, Maximum Borrowing Capacity | $ 125,000 |  |  |
Maximum Senior Leverage Ratio Requirement | 2.50 |  |  |
Debt Instrument, Covenant, Minimum Consolidated Earnings Before Interest, Taxes, Depreciation, and Amortization | $ 31,500 |  |  |
Long-term Line of Credit, Total |  | 86,800 |  |
Letters of Credit Outstanding, Amount |  | 1,600 | 1,600 |
Line of Credit Facility, Remaining Borrowing Capacity |  | $ 37,000 |  |
Wells Fargo Bank, N.A. [Member] | Revolving Credit Facility [Member] |  |  |  |
Long-term Line of Credit, Total |  |  | $ 0 |
Debt, Weighted Average Interest Rate |  | 1.85% | 1.73% |
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 |  | 1.75% |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage |  | 0.30% |  |
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 |  | 2.25% |  |
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage |  | 0.40% |  |

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- Definition The minimum amount of consolidated earnings before interest, taxes, depreciation, and amortization pursuant to the debt agreement. + 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. + Details
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- Definition Amount of interest capitalized during the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6450988&loc=d3e26243-108391 + Details
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- 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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- 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 of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding). + 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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