Note 13 - Retirement, Savings and Deferred Compensation Plans - Components of SERP Expense (Details) - Supplemental Employee Retirement Plan [Member] - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Service cost	$ 98	$ 92	$ 296	$ 277
Interest cost	225	221	677	664
Net amortization	19	18	59	53
Net periodic benefit cost	$ 342	$ 331	$ 1,032	$ 994