Marketable Securities (Available For Sale Securities) (Details) (USD $) In Thousands, unless otherwise specified	Sep. 29, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 73,156	$ 80,101
Gross Unrealized Holding Gains	10,312	9,247
Gross Unrealized Holding Losses	150
Available-for-sale Securities, Fair Value, Total	83,318	89,348
Equity Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,136	1,713
Gross Unrealized Holding Gains	8,752	7,735
Available-for-sale Securities, Fair Value, Total	9,888	9,448
Municipal Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	72,020	78,388
Gross Unrealized Holding Gains	1,560	1,512
Gross Unrealized Holding Losses	150
Available-for-sale Securities, Fair Value, Total	$ 73,430	$ 79,900

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