Note 4 - Defined Benefit Plan - Defined Benefit Plan Activity (Details) - Net Periodic Benefit Income [Member] - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 287	$ 248
Interest cost	341	324
Expected return on plan assets	(739)	(692)
Net periodic benefit income	$ (111)	$ (120)