Note G - Cash, Cash Equivalents And Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Apr. 02, 2023	Dec. 31, 2022
Amortized Cost	$ 29,125	$ 24,993
Fair Value	29,013	24,863
Gross Unrealized Gains	8	22
Gross Unrealized Losses	119	152
Fixed Rate Municipal Bonds [Member]
Amortized Cost	10,471	11,460
Fair Value	10,453	11,405
Gross Unrealized Gains	0	0
Gross Unrealized Losses	18	58
Certificates of Deposit [Member]
Amortized Cost	14,250	9,895
Fair Value	14,156	9,820
Gross Unrealized Gains	8	22
Gross Unrealized Losses	101	94
Variable Rate Demand Obligation [Member]
Amortized Cost	4,404	3,638
Fair Value	4,404	3,638
Gross Unrealized Gains	0	0
Gross Unrealized Losses	$ 0	$ 0

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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