Restructuring - Narrative (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018 USD ($)	Oct. 01, 2017 USD ($)	Sep. 30, 2018 USD ($) Employee	Oct. 01, 2017 USD ($)
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 88	$ 69	$ 187	$ 165
Supply Chain
Restructuring Cost and Reserve [Line Items]
Restructuring charges	89
Restructuring charges recorded to date	100		100
Supply Chain | Cost of products sold
Restructuring Cost and Reserve [Line Items]
Restructuring charges	14
Supply Chain | Other (income) expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	34
Supply Chain | Minimum
Restructuring Cost and Reserve [Line Items]
Restructuring estimated cost	1,900		1,900
Cost savings expected	600		600
Supply Chain | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring estimated cost	2,300		2,300
Cost savings expected	800		$ 800
Estimated cost settled with cash (as a percent)			70.00%
Medical Devices
Restructuring Cost and Reserve [Line Items]
Restructuring charges	101		$ 473
Restructuring charges recorded to date	2,400		$ 2,400
Number of positions eliminated | Employee			2,650
Number of positions eliminated and receiving severance | Employee			1,950
Medical Devices | Cost of products sold
Restructuring Cost and Reserve [Line Items]
Restructuring charges	9
Medical Devices | Other (income) expense
Restructuring Cost and Reserve [Line Items]
Restructuring charges	45
Medical Devices | Minimum
Restructuring Cost and Reserve [Line Items]
Positions eliminated (as a percent)			5.00%
Medical Devices | Maximum
Restructuring Cost and Reserve [Line Items]
Restructuring estimated cost	2,400		$ 2,400
Medical Devices
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 200	$ 200	$ 400	$ 500
Medical Devices | Supply Chain | Minimum
Restructuring Cost and Reserve [Line Items]
Period for activity			4 years
Medical Devices | Supply Chain | Maximum
Restructuring Cost and Reserve [Line Items]
Period for activity			5 years