Note K - Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Loss by Component (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2021	Mar. 31, 2021	Jun. 30, 2022	Jun. 30, 2021
Balance	$ (20,571)	$ (24,715)	$ (54,423)	$ (53,123)	$ (24,715)	$ (53,123)
Total other comprehensive (loss) income, net of tax	(2,029)	506	856	278	(1,523)	1,134
Balance	(17,711)	(20,571)	(42,559)	(54,423)	(17,711)	(42,559)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance		(54,394)		(68,544)	(54,394)	(68,544)
Other comprehensive loss, net of tax, before reclassifications					0	0
Amounts reclassified from accumulated other comprehensive income, net of tax, to other, net, on the condensed consolidated statements of comprehensive income					1,588	1,596
Total other comprehensive (loss) income, net of tax					1,588	1,596
Balance	(52,806)		(66,948)		(52,806)	(66,948)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance		1,066		2,933	1,066	2,933
Other comprehensive loss, net of tax, before reclassifications					(3,111)	(462)
Amounts reclassified from accumulated other comprehensive income, net of tax, to other, net, on the condensed consolidated statements of comprehensive income					0	0
Total other comprehensive (loss) income, net of tax					(3,111)	(462)
Balance	(2,045)		2,471		(2,045)	2,471
AOCI Attributable to Parent [Member]
Balance	(52,822)	(53,328)	(65,333)	(65,611)	(53,328)	(65,611)
Other comprehensive loss, net of tax, before reclassifications					(3,111)	(462)
Amounts reclassified from accumulated other comprehensive income, net of tax, to other, net, on the condensed consolidated statements of comprehensive income					1,588	1,596
Total other comprehensive (loss) income, net of tax	(2,029)	506	856	278	(1,523)	1,134
Balance	$ (54,851)	$ (52,822)	$ (64,477)	$ (65,333)	$ (54,851)	$ (64,477)