Note 10 - Benefit Plans - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021
Interest cost on projected benefit obligation		$ 508
Service cost on benefits earned during the period		185
Pension Plan [Member]
Interest cost on projected benefit obligation	$ 0	171
Expected return on plan assets	0	(597)
Recognized actuarial loss	0	376
Settlement loss	0	0
Pension plan termination charge	0	7,821
Net periodic pension cost after settlements	0	7,771
Service cost on benefits earned during the period		0
Supplemental Employee Retirement Plan [Member]
Interest cost on projected benefit obligation	401	337
Recognized actuarial loss	1,715	1,499
Net periodic pension cost after settlements	2,319	2,021
Service cost on benefits earned during the period	$ 203	$ 185