Income Taxes (Details 2) - USD ($) $ in Millions	Dec. 26, 2015	Dec. 27, 2014
Income Tax Disclosure [Abstract]
Deferred Tax Liability Not Recognized, Cumulative Amount of Temporary Differences	$ 2,300
Net deferred tax assets (liabilities) [Abstract]
Operating loss and tax credit carryforwards	239	$ 271
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	282	162
Employee benefits	154	238
Share-based compensation	126	119
Self-insured casualty claims	36	42
Lease related liabilities	112	119
Various liabilities	82	73
Deferred Tax Assets, Property, Plant and Equipment	33	39
Deferred income and other	86	102
Gross deferred tax assets	1,150	1,165
Deferred tax asset valuation allowances	(250)	(228)
Net deferred tax assets	900	937
Intangible assets, including goodwill	(130)	(148)
Property, plant and equipment	(56)	(63)
Other	(70)	(104)
Gross deferred tax liabilities	(256)	(315)
Net deferred tax assets (liabilities)	644	622
Reported in Consolidated Balance Sheets as:
Deferred Tax Assets, Net of Valuation Allowance, Current	676	653
Other liabilities and deferred credits	(32)	(31)
Net deferred tax assets (liabilities)	$ 644	$ 622