Other Comprehensive Income / (Loss) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 26, 2015	Jun. 27, 2014	Jun. 26, 2015	Jun. 27, 2014
Equity [Abstract]
Total comprehensive earnings, net of tax	$ 565	$ 544	$ 1,005	$ 958
Pension and Other Post-Employment Benefits
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance, Net of Tax			(611)
Other Comprehensive Income (Loss)
Loss Before Reclassifications			0
Amounts Reclassified to Net Earnings			36
Tax Expense			(15)
Total Other Comprehensive Income (Loss)			21
Ending Balance, Net of Tax	(590)		(590)
Other
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance, Net of Tax			(55)
Other Comprehensive Income (Loss)
Loss Before Reclassifications			(11)
Amounts Reclassified to Net Earnings			0
Tax Expense			0
Total Other Comprehensive Income (Loss)			(11)
Ending Balance, Net of Tax	(66)		(66)
Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning Balance, Net of Tax			(666)
Other Comprehensive Income (Loss)
Loss Before Reclassifications			(11)
Amounts Reclassified to Net Earnings			36
Tax Expense			(15)
Total Other Comprehensive Income (Loss)			10
Ending Balance, Net of Tax	$ (656)		$ (656)