Note 7 - Accrued Retirement Benefits - Changes in Benefit Obligations and Plan Assets (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Benefit obligations	$ 15,552	$ 16,537
Interest cost	738	783
Actuarial gain	(27)	(580)
Benefits paid	(2,314)	(1,188)
Benefit obligations	13,949	15,552
Fair value of plan assets at beginning of year	13,860	13,783
Actual return on plan assets	(231)	1,137
Employer contributions	126	128
Benefits paid	(2,314)	(1,188)
Fair value	11,441	13,860
Funded status	(2,508)	(1,692)
Accumulated benefit obligations	$ (13,949)	$ (15,552)
Expected long-term return on plan assets	5.40%	5.25%