Note G - Cash, Cash Equivalents And Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Oct. 01, 2023	Dec. 31, 2022
Amortized Cost	$ 25,061	$ 24,993
Fair Value	24,966	24,863
Gross Unrealized Gains	0	22
Gross Unrealized Losses	95	152
Fixed Rate Municipal Bonds [Member]
Amortized Cost	2,091	11,460
Fair Value	2,087	11,405
Gross Unrealized Gains	0	0
Gross Unrealized Losses	4	58
Certificates of Deposit [Member]
Amortized Cost	18,791	9,895
Fair Value	18,700	9,820
Gross Unrealized Gains		22
Gross Unrealized Losses	91	94
Variable Rate Demand Obligation [Member]
Amortized Cost	4,179	3,638
Fair Value	4,179	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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