Other Comprehensive Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 26, 2014	Dec. 27, 2013	Dec. 28, 2012
Accumulated Other Comprehensive Income (Loss) [Line Items]
Comprehensive Earnings	$ 1,784us-gaap_ComprehensiveIncomeNetOfTax	$ 2,277us-gaap_ComprehensiveIncomeNetOfTax	$ 1,802us-gaap_ComprehensiveIncomeNetOfTax
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(523)	(936)	(875)
Other Comprehensive Income (Loss):
Income (Loss) Before Reclassifications	(293)	534	(181)
Loss (Income) Reclassified to Net Earnings	62	109	87
Tax (Expense) Benefit	88	(230)	33
Other Comprehensive (Loss) Income, Net of Tax	(143)	413	(61)
Ending Balance	(666)	(523)	(936)
Pension and Other Post-Employment Benefits [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(462)	(851)	(799)
Other Comprehensive Income (Loss):
Income (Loss) Before Reclassifications	(297)	510	(172)
Loss (Income) Reclassified to Net Earnings	60	111	88
Tax (Expense) Benefit	88	(232)	32
Other Comprehensive (Loss) Income, Net of Tax	(149)	389	(52)
Ending Balance	(611)	(462)	(851)
Other
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning Balance	(61)	(85)	(76)
Other Comprehensive Income (Loss):
Income (Loss) Before Reclassifications	4	24	(9)
Loss (Income) Reclassified to Net Earnings	2	(2)	(1)
Tax (Expense) Benefit	0	2	1
Other Comprehensive (Loss) Income, Net of Tax	6	24	(9)
Ending Balance	$ (55)	$ (61)	$ (85)

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount of tax expense (benefit) allocated to other comprehensive income (loss) attributable to parent entity.

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Amount before tax of reclassification adjustments of other comprehensive income (loss).

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