Financial Instruments (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 25, 2011	Sep. 30, 2012	Sep. 25, 2011	Dec. 25, 2011
Debt Instrument [Line Items]
Carrying Cost	$ 1,398,906	$ 1,405,071	$ 1,398,906	$ 1,405,071	$ 1,400,872
Fair Value	1,595,783	1,538,000	1,595,783	1,538,000	1,524,266
Principal Amount	1,384,895	1,384,895	1,384,895	1,384,895	1,384,895
Interest Rate Swap 6.125% Note Due 2014 [Member]
Debt Instrument [Line Items]
Fair value adjustment, interest rate swap	14,011	20,176	14,011	20,176	15,977
Derivative [Line Items]
Interest rate swap notional amount	400,000	400,000	400,000	400,000	400,000
Interest rate swap maturity date			2014	2014	2014
Fair value, interest rate swap	14,011	20,176	14,011	20,176	15,977
Gain (loss) from interest rate swap	(651)	2,040	(1,966)	7,390
Notes 6.125% Due 2014 [Member]
Debt Instrument [Line Items]
Carrying Cost	439,011	445,176	439,011	445,176	440,977
Fair Value	459,680	467,245	459,680	467,245	462,868
Principal Amount	425,000	425,000	425,000	425,000	425,000
Maturity Date			2014	2014	2014
Interest Rate	6.125%	6.125%	6.125%	6.125%	6.125%
Fair value adjustment, interest rate swap	14,011	20,176	14,011	20,176	15,977
Derivative [Line Items]
Fair value, interest rate swap	14,011	20,176	14,011	20,176	15,977
Notes 6.30% Due 2017 [Member]
Debt Instrument [Line Items]
Carrying Cost	350,000	350,000	350,000	350,000	350,000
Fair Value	409,325	402,780	409,325	402,780	400,400
Principal Amount	350,000	350,000	350,000	350,000	350,000
Maturity Date			2017	2017	2017
Interest Rate	6.30%	6.30%	6.30%	6.30%	6.30%
Debentures 6.60% Due 2028 [Member]
Debt Instrument [Line Items]
Carrying Cost	109,895	109,895	109,895	109,895	109,895
Fair Value	127,478	120,775	127,478	120,775	120,148
Principal Amount	109,895	109,895	109,895	109,895	109,895
Maturity Date			2028	2028	2028
Interest Rate	6.60%	6.60%	6.60%	6.60%	6.60%
Notes 6.35% Due 2040 [Member]
Debt Instrument [Line Items]
Carrying Cost	500,000	500,000	500,000	500,000	500,000
Fair Value	599,300	547,200	599,300	547,200	540,850
Principal Amount	$ 500,000	$ 500,000	$ 500,000	$ 500,000	$ 500,000
Maturity Date			2040	2040	2040
Interest Rate	6.35%	6.35%	6.35%	6.35%	6.35%