Note K - Comprehensive Income (Loss) - Changes in Accumulated Other Comprehensive Loss By Component (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Balance	$ (49,683)	$ (19,184)
Total other comprehensive income (loss), net of tax	51	(10,833)
Balance	(44,291)	(32,000)
Adoption of ASU 2018-02		(11,355)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Balance	(63,887)	(46,584)
Other comprehensive loss, net of tax, before reclassifications
Amounts reclassified from accumulated other comprehensive income (loss), net of tax, to other, net, on the condensed consolidated statements of comprehensive income	609	550
Total other comprehensive income (loss), net of tax	609	(10,805)
Balance	(63,278)	(57,389)
Adoption of ASU 2018-02		(11,355)
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Balance	753	101
Other comprehensive loss, net of tax, before reclassifications	(558)	(28)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax, to other, net, on the condensed consolidated statements of comprehensive income
Total other comprehensive income (loss), net of tax	(558)	(28)
Balance	195	73
Adoption of ASU 2018-02
AOCI Attributable to Parent [Member]
Balance	(63,134)	(46,483)
Other comprehensive loss, net of tax, before reclassifications	(558)	(28)
Amounts reclassified from accumulated other comprehensive income (loss), net of tax, to other, net, on the condensed consolidated statements of comprehensive income	609	550
Total other comprehensive income (loss), net of tax	51	(10,833)
Balance	$ (63,083)	(57,316)
Adoption of ASU 2018-02		$ (11,355)