Nature of Operations and Significant Accounting Policies (Amortization of Gain from Property Disposition) (Details) (USD $) In Millions, unless otherwise specified	0 Months Ended	3 Months Ended
	Nov. 30, 2011 mi	Mar. 30, 2012	Dec. 30, 2011
Significant Acquisitions and Disposals [Line Items]
Total number of rail route miles		21,000
Current portion, included in Other Current Liabilities [Member]
Significant Acquisitions and Disposals [Line Items]
Deferred gain on sale of real estate		$ 95	$ 95
Long term portion, included in Other Long-term Liabilities [Member]
Significant Acquisitions and Disposals [Line Items]
Deferred gain on sale of real estate		18	37
SunRail Transaction - Sale of Corridor [Member]
Significant Acquisitions and Disposals [Line Items]
Total number of rail route miles	61
Proceeds from sale of operating rail corridor	173
Obligation to invest in routine captial expenditures and maintenance		500
Obligation to invest in routine captial expenditures and maintenance, term (in years)		8 years
Gain on sale of real estate		19
Deferred gain on sale of real estate	146	113	132
SunRail Transaction - Sale of Corridor [Member] | Maximum [Member]
Significant Acquisitions and Disposals [Line Items]
Governmental grants received from sale of operating rail corridor	259
Total consideration given from sale of operating rail corridor	$ 432