Income Taxes (Deferred Income Tax Assets and Liabilities) (Details) (USD $) In Millions, unless otherwise specified	Dec. 27, 2013	Dec. 28, 2012
Components of Deferred Tax Assets [Abstract]
Pension Plans	$ 67	$ 249
Other Employee Benefit Plans	299	292
Other	257	278
Total	623	819
Components of Deferred Tax Liabilities [Abstract]
Accelerated Depreciation	8,868	8,544
Other	262	252
Total	9,130	8,796
Net Deferred Income Tax Liabilities	$ 8,507	$ 7,977