Fair Value Measurements (Schedule Of Assets And Liabilities Measured At Fair Value) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 25, 2010
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Category, Assets	$ 1,700	$ 400
Level 2 [Member] | Commodity Contracts - Fuel [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Category, Assets		253
Fair Value Measurement Category, Liabilities	251
Level 2 [Member] | Foreign Exchange Contracts [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Measurement Category, Assets	341
Fair Value Measurement Category, Liabilities	$ 92	$ 434