Investments (Amortized Cost And Fair Value Of Debt And Equity Securities Classified As AFS By Maturities) (Details) (USD $) In Thousands	Jun. 25, 2011	Dec. 25, 2010
Amortized Cost
Due in one year or less	$ 380,707	$ 332,992
Due after one year through five years	2,060,402	1,499,176
Due after five years through ten years	338,913	337,677
Due after ten years	569,104	630,051
Available-for-sale securities, debt maturities, amortized cost	3,349,126	2,799,896
Total amortized cost	3,747,539	3,019,633
Fair Value
Due in one year or less	382,906	336,282
Due after one year through five years	2,087,807	1,506,731
Due after five years through ten years	342,460	335,056
Due after ten years	585,981	640,379
Available-for-sale securities, debt maturities, fair value	3,399,154	2,818,448
Fair value of available-for-sale securities	3,838,894	3,096,033
Restricted Investments [Member]
Amortized Cost
Total amortized cost	170,000
Fair Value
Fair value of available-for-sale securities	170,776
Equity Securities [Member]
Amortized Cost
Total amortized cost	228,413	219,737
Fair Value
Fair value of available-for-sale securities	$ 268,964	$ 277,585