Investments (Available-For-Sale Investments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 25, 2010
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 67,702	$ 76,907
Gross Unrealized Gains	931	942
Gross Unrealized Losses	145	182
Fair Market Value	68,488	77,667
Money Market Investments [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	1,989	535
Gross Unrealized Gains
Gross Unrealized Losses
Fair Market Value	1,989	535
Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	3,017	3,458
Gross Unrealized Gains	61	64
Gross Unrealized Losses	18	8
Fair Market Value	3,060	3,514
Corporate Bonds And Direct Obligations Of Government Agencies [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	51,014	60,330
Gross Unrealized Gains	819	872
Gross Unrealized Losses	126	151
Fair Market Value	51,707	61,051
U.S. Treasury Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,682	12,584
Gross Unrealized Gains	51	6
Gross Unrealized Losses	1	23
Fair Market Value	$ 11,732	$ 12,567

For an unclassified balance sheet, total of debt securities categorized neither as held-to-maturity nor trading.

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+ 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