Marketable Securities (Available For Sale Securities) (Details) (USD $) In Thousands, unless otherwise specified	6 Months Ended	12 Months Ended
Jun. 29, 2013	Dec. 29, 2012
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 68,652	$ 73,976
Gross Unrealized Holding Gains	8,195	9,022
Gross Unrealized Holding Losses	(1,570)	(497)
Fair Value	75,277	82,501
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,074	1,136
Gross Unrealized Holding Gains	7,467	7,714
Fair Value	8,541	8,850
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	67,578	72,840
Gross Unrealized Holding Gains	728	1,308
Gross Unrealized Holding Losses	(1,570)	(497)
Fair Value	$ 66,736	$ 73,651

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 320

-SubTopic 10

-Section 25

-Paragraph 1

-Subparagraph (b)

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-Publisher FASB

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.2)

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Amount of unrealized gain before deducting unrealized loss on investments in debt and equity securities classified as available-for-sale securities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount of unrealized loss before deducting unrealized gain on investments in available-for-sale securities.

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-Name Accounting Standards Codification

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