Marketable Securities (Available For Sale Securities) (Details) (USD $) In Thousands, unless otherwise specified	Mar. 30, 2013	Dec. 29, 2012
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 69,167	$ 73,976
Gross Unrealized Holding Gains	10,355	9,022
Gross Unrealized Holding Losses	(843)	(497)
Available-for-sale Securities, Fair Value, Total	78,679	82,501
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,136	1,136
Gross Unrealized Holding Gains	8,718	7,714
Available-for-sale Securities, Fair Value, Total	9,854	8,850
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	68,031	72,840
Gross Unrealized Holding Gains	1,637	1,308
Gross Unrealized Holding Losses	(843)	(497)
Available-for-sale Securities, Fair Value, Total	$ 68,825	$ 73,651

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

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+ Details

- Definition

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+ Details

- Definition

This item represents the gross unrealized gains for securities, at a point in time, which are categorized neither as held-to-maturity nor trading securities.

+ References+ Details