Note H - Employee Benefit Plans - Net Period of Net Periodic Cost (Details) - Pension Plan [Member] - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Interest cost	$ 5,894	$ 7,254
Expected return on plan assets	(5,538)	(4,446)
Recognized actuarial loss	3,247	2,930
Net periodic benefit cost	3,603	5,738
Net loss	4,657	5,948
Net cost recognized in net periodic benefit cost and other comprehensive loss	$ 8,260	$ 11,686

Amount recognized in net periodic benefit cost (credit) and other comprehensive (income) loss.

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Amount of gain (loss), recognized immediately as component of net periodic benefit (cost) credit, for change in value of benefit obligation or plan assets from experience different from that assumed, change in actuarial assumption, or consequence of temporarily deviating from substantive plan. Includes, but is not limited to, amount in excess of ten percent of greater of fair value of plan assets or benefit obligation.

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Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan.

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Amount of cost recognized for passage of time related to defined benefit plan.

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Amount of net periodic benefit cost (credit) for defined benefit plan.

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Amount, before tax, after reclassification adjustment, of (increase) decrease in accumulated other comprehensive income for defined benefit plan.

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