For an unclassified balance sheet, this item represents investments in debt securities which are categorized as held-to-maturity. The held-to-maturity category is for those securities that the entity has the positive intent and ability to hold until maturity.

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+ Details

Short-Term Investments (Details) (USD $) In Thousands, unless otherwise specified			0 Months Ended
	Sep. 23, 2012	Dec. 25, 2011	Sep. 23, 2012 Minimum [Member]	Sep. 23, 2012 Maximum [Member]	Sep. 23, 2012 Commercial Paper, Not Included with Cash and Cash Equivalents [Member]	Sep. 23, 2012 US Treasury Securities [Member]
Schedule of Held-to-maturity Securities [Line Items]
Short-term investments	$ 279,740	$ 104,846
Carrying value of short-term investments					$ 30,000	$ 250,000
Term of short term investments			1 month	10 months