Note 12 - Employee Retirement Plans (Details Textual) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Credit Risk of Plan Assets, Long Duration Corporate Bonds	54.00%
Liquidity Risk Long-term Investments In Private Equity and Real Estate	1.00%
Defined Contribution Plan, Cost	$ 117,000	$ 98,000	$ 76,000
Equity Securities [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	40.00%
Bond Investments [Member]
Defined Benefit Plan, Plan Assets, Target Allocation, Percentage	60.00%
Minimum [Member]
Percent To Yield	10.00%
Maximum [Member]
Percent To Yield	40.00%
Pension Plan [Member]
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	$ 1,100,000	124,000
Defined Benefit Plan, Accumulated Benefit Obligation	3,500,000	4,500,000
Pension Plan [Member] | UNITED STATES
Defined Benefit Plan Voluntary Contributions by Employer	0
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 15,000	$ 16,000
Weighted Average Discount Rate, Rounded Amount	2.63%	0.37%
Pension Plan [Member] | Foreign Plan [Member]
Defined Benefit Plan Voluntary Contributions by Employer	$ 24,000
Defined Benefit Plan, Expected Future Employer Contributions, Next Fiscal Year	49,000
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 8,000	$ 31,000
Weighted Average Discount Rate, Rounded Amount	1.26%	0.18%
Other Postretirement Benefits Plan [Member]
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 31,000	$ 9,000
Cap On Contribution Toward Future Retiree Medical Coverage	120.00%
Percentage Of Cost To Be Paid By Employees For Retiree Medical Upon Retirement	100.00%
Defined Benefit Plan, Benefit Obligation, Actuarial Gain (Loss)	$ 209,000	$ 105,000
Weighted Average Discount Rate, Rounded Amount	2.59%	0.30%
Other Postretirement Benefits Plan [Member] | UNITED STATES
Defined Benefit Plan, Plan Assets, Contributions by Employer	$ 0	$ 0