Note 4 - Periodic Pension Expense (Details Textual) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($) yr
Defined Benefit Plans Number of Plans		2		2
Defined Benefit Plans Retirement Age (Year) | yr				65
Defined Benefit Plans Number Of Plans, Terminated		2		2
Defined Benefit Plan, Termination Charge | $	$ 0	$ 0	$ 0	$ 6,945