Marketable Securities (Schedule Of Marketable Securities) (Details) - USD ($) $ in Thousands	Jun. 29, 2019	Dec. 29, 2018
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	$ 47,433	$ 46,699
Gross Unrealized Holding Gains	1,874	426
Gross Unrealized Holding Losses	(3)	(53)
Fair Value	57,376	54,298
Equity Securities [Member] \| Fair Value, Inputs, Level 1 [Member]
Debt Securities, Available-for-sale [Line Items]
Equity securities, Fair Value	8,074	7,226
Municipal Bonds [Member] \| Fair Value, Inputs, Level 2 [Member]
Debt Securities, Available-for-sale [Line Items]
Amortized Cost	47,433	46,699
Gross Unrealized Holding Gains	1,874	426
Gross Unrealized Holding Losses	(3)	(53)
Fair Value	$ 49,304	$ 47,072

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118939692&loc=d3e27161-111563

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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+ References

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Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=99377092&loc=SL75136599-209740

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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