Segments of Business and Geographic Areas - Schedule of Revenue from External Customers and Long-Lived Assets, by Geographical Areas (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2019	Apr. 01, 2018
Sales by geographic area
Sales	$ 20,021	$ 20,009
Percentage Change In Sales By Geographic Area	0.10%
United States
Sales by geographic area
Sales	$ 10,129	9,951
Percentage Change In Sales By Geographic Area	1.80%
Europe
Sales by geographic area
Sales	$ 4,609	4,797
Percentage Change In Sales By Geographic Area	(3.90%)
Western Hemisphere, excluding U.S.
Sales by geographic area
Sales	$ 1,503	1,567
Percentage Change In Sales By Geographic Area	(4.10%)
Asia-Pacific, Africa
Sales by geographic area
Sales	$ 3,780	$ 3,694
Percentage Change In Sales By Geographic Area	2.30%