Income Taxes - Net Deferred Tax Assets and Liabilities (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 30, 2012	Dec. 25, 2011
Income Tax Disclosure [Abstract]
Retirement, postemployment and deferred compensation plans	$ 400,292	$ 447,156
Accruals for other employee benefits, compensation, insurance and other	36,959	39,572
Accounts receivable allowances	6,111	7,114
Other	84,527	109,946
Gross deferred tax assets	527,889	603,788
Valuation allowance	(42,138)	(39,824)
Net deferred tax assets	485,751	563,964
Property, plant and equipment	108,763	143,308
Intangible assets	0	42,150
Investments in joint ventures	13,430	15,095
Other	4,266	10,073
Gross deferred tax liabilities	126,459	210,626
Net deferred tax asset	359,292	353,338
Deferred tax asset – current	58,214	73,055
Deferred tax asset – long-term	$ 301,078	$ 280,283
Valuation allowance, period for recoverability measurement	3 years