Employee Benefits Narrative (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Oct. 03, 2015	Sep. 27, 2014	Oct. 03, 2015	Sep. 27, 2014
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost), pre-tax	$ 66	$ 19	$ 66	$ 10
Prior service credit (cost), after-tax	41	$ 12	$ 41	$ 6
Nonpension postretirement
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost), pre-tax	84
Prior service credit (cost), after-tax	53
Pension
Defined Benefit Plan Disclosure [Line Items]
Prior service credit (cost), pre-tax	(17)
Prior service credit (cost), after-tax	$ (11)