Note 6 - Employee Benefit Plans - Schedule of Beginning and Ending Balances of Accumulated Postretirement Benefit Obligations (Details) - Other Postretirement Benefits Plan [Member] - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Accumulated post-retirement benefit obligations at the beginning of the year	$ 4,262,000	$ 4,062,000
Interest cost	216,000	192,000
Actuarial (gain)/loss	(231,000)	152,000
Benefits paid	(150,000)	(144,000)
Accumulated post-retirement benefit obligations at the end of the year	$ 4,097,000	$ 4,262,000