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Note 3 - Credit Agreement (Details Textual) $ in Millions		9 Months Ended
	Jun. 30, 2023 USD ($)	Sep. 30, 2025 USD ($)	Dec. 31, 2024 USD ($)
Letters of Credit Outstanding, Amount		$ 1.6
Wells Fargo Bank, N.A. [Member]
Line of Credit Facility, Maximum Borrowing Capacity	$ 125.0
Line of Credit Facility, Increase (Decrease), Net	$ 50.0
Maximum Senior Leverage Ratio Requirement	3
Debt Instrument, Covenant, Minimum Consolidated Earnings Before Interest, Taxes, Depreciation, and Amortization	$ 35.0
Wells Fargo Bank, N.A. [Member] | Revolving Credit Facility [Member]
Long-Term Line of Credit		27.6	$ 24.7
Letters of Credit Outstanding, Amount		1.6	$ 1.6
Line of Credit Facility, Remaining Borrowing Capacity		$ 96.0
Debt, Weighted Average Interest Rate		5.84%	6.68%
Wells Fargo Bank, N.A. [Member] | Revolving Credit Facility [Member] | Minimum [Member]
Debt Instrument, Basis Spread on Variable Rate		0.50%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.20%
Wells Fargo Bank, N.A. [Member] | Revolving Credit Facility [Member] | Maximum [Member]
Debt Instrument, Basis Spread on Variable Rate		2.00%
Line of Credit Facility, Unused Capacity, Commitment Fee Percentage		0.25%

X

- Definition

The minimum amount of consolidated earnings before interest, taxes, depreciation, and amortization pursuant to the debt agreement.

+ References

No definition available.

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X

- Definition

The maximum senior leverage ratio requirement.

+ References

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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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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

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X

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 944
-SubTopic 605
-Name Accounting Standards Codification
-Section 55
-Paragraph 15
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477548/944-605-55-15

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X

- 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

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-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-SubTopic 10
-Topic 210
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X

- Definition

Amount of increase (decrease) of the credit facility.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S50
-Paragraph 1
-Publisher FASB
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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

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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://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 10
-Name Accounting Standards Codification
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-Paragraph 6
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X

- 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.

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