Accumulated Other Comprehensive (Loss) Income (AOCI), Summary of AOCI Balances Including Amounts Reclassified from AOCI into Net Income (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 29, 2018	Jun. 30, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	$ 5,083
Other comprehensive (loss) income before reclassifications, net of tax	(49)	$ 72
Amounts reclassified from AOCI, net of tax	26	18
Net current period other comprehensive (loss) income	(23)	90
Ending Balance	5,444
Accumulated Other Comprehensive Loss [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(691)	(726)
Ending Balance	(714)	(636)
Foreign Currency Translation [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(54)	(178)
Other comprehensive (loss) income before reclassifications, net of tax	(39)	71
Amounts reclassified from AOCI, net of tax	0	0
Net current period other comprehensive (loss) income	(39)	71
Ending Balance	(93)	(107)
Unrealized Gains (Losses) on Hedging Instruments [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	9	6
Other comprehensive (loss) income before reclassifications, net of tax	(10)	1
Amounts reclassified from AOCI, net of tax	(1)	(1)
Net current period other comprehensive (loss) income	(11)	0
Ending Balance	(2)	6
Unrecognized (Losses) Gains and Prior Service Cost, Net [Member]
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Beginning Balance	(646)	(554)
Other comprehensive (loss) income before reclassifications, net of tax	0	0
Amounts reclassified from AOCI, net of tax	27	19
Net current period other comprehensive (loss) income	27	19
Ending Balance	$ (619)	$ (535)