Note 9 - Employee Retirement Plans (Details Textual) - USD ($) shares in Thousands, $ in Thousands		3 Months Ended		12 Months Ended			36 Months Ended
	Oct. 31, 2021	Dec. 31, 2023	Jun. 30, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2023
Defined Benefit Plan, Plan Assets, Contributions by Employer				$ 1,603	$ 1,603	$ 1,603
Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash				(2,313)	$ 0	0
Defined Benefit Plan Concentration Risk Assets Equity Securities Difference Plan Assets And Liabilities					25.00%
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase for Purchase				3,000	$ 3,000
Defined Benefit Plan, Expected Amortization of Prior Service Cost (Credit), Next Fiscal Year		$ 0		$ 0			$ 0
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate		5.25%		5.25%	5.47%		5.25%
Pension Plan [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer							$ 0
Defined Benefit Plan, Benefit Obligation, Payment for Settlement		$ 2,200	$ 11,800
Pension and Other Postretirement Benefits Expense (Reversal of Expense), Noncash		$ 500	$ (1,800)
Supplemental Employee Retirement Plan [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer				$ 1,600	$ 1,600	1,600
Defined Contribution Saving Plan, A401 K [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer				$ 400	$ 300	$ 100
Defined Contribution Plan, Percent, Contributed By Employee Minimum				2.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent				75.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Match	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent of Employees' Gross Pay	6.00%
Defined Benefit Plan, Plan Assets, Employer, Related Party, Number of Shares (in shares)		0		0	0		0
Multinational Retirement Plan [Member]
Defined Contribution Plan, Percent, Contributed By Employee Minimum				1.00%
Defined Contribution Plan, Maximum Annual Contributions Per Employee, Percent				50.00%
Merchant Navy Officers Pension Fund [Member]
Postemployment Benefits Liability		$ 1,500		$ 1,500	$ 1,300		$ 1,500
Postemployment Benefits, Period Expense				$ 200