Note G - Cash, Cash Equivalents And Marketable Securities - Summary of Marketable Securities (Details) - USD ($) $ in Thousands	Sep. 27, 2020	Dec. 31, 2019
Amortized Cost	$ 78,807	$ 78,562
Fair Value	79,098	78,733
Gross Unrealized Gains	291	176
Gross Unrealized Losses	0	5
Nontaxable Municipal Bonds [Member]
Amortized Cost	49,954	39,313
Fair Value	50,245	39,484
Gross Unrealized Gains	291	176
Gross Unrealized Losses	0	5
Variable Rate Demand Obligation [Member]
Amortized Cost	28,853	39,249
Fair Value	28,853	39,249
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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