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Reorganization of Business - Reorganization of Businesses Accruals (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jul. 01, 2017	Jun. 30, 2018	Jul. 01, 2017
Restructuring Reserve [Roll Forward]
January 1, 2018			$ 50
Additional Charges			52
Adjustments	$ (3)		(14)
Amount Used			(36)
June 30, 2018	52		52
Exit costs
Restructuring Reserve [Roll Forward]
January 1, 2018			9
Additional Charges	1		3	$ 4
Adjustments			0
Amount Used			(3)
June 30, 2018	9		9
Employee separation costs
Restructuring Reserve [Roll Forward]
January 1, 2018			41
Additional Charges	27	$ 8	49	23
Adjustments		$ (5)	(14)	$ (5)
Amount Used			(33)
June 30, 2018	$ 43		$ 43