Financial Instruments (Financial Instruments Activity Included As Part Of Accumulated Other Comprehensive Income, Net Of Tax) (Details) (USD $) In Thousands	9 Months Ended
	Sep. 25, 2011	Sep. 26, 2010
Financial Instruments [Abstract]
Balance at beginning of year	$ (15,262)	$ (17,343)
Additions and revaluations	(1,014)	(5,864)
Loss reclassified from AOCI into income	6,675	5,831
Tax rate adjustment	(153)	23
Balance at end of period	$ (9,754)	$ (17,353)