Note 6 - Employee Benefit Plans - Schedule of Financial Information for Plan (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Benefit cost	$ 313	$ 279
Other Postretirement Benefits Plan [Member]
Interest cost	216	192
Recognized actuarial loss	97	87
Benefits paid	$ 150	$ 144

Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of 10 percent of greater of fair value of plan assets or benefit obligation.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 45
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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- Definition

Amount of payment to participant of defined benefit plan which decreases benefit obligation. For pension plan, payment includes, but is not limited to, pension benefits and death benefits. For other postretirement plan, payment includes, but is not limited to, prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
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-Section 50
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- Definition

Amount of cost recognized for passage of time related to defined benefit plan.

+ References

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- Definition

Amount of net periodic benefit cost (credit) for defined benefit plan.

+ References

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