Employee Benefits - Components of Plan Benefit Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 29, 2019	Jun. 30, 2018	Jun. 29, 2019	Jun. 30, 2018
Global | Pension
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9	$ 22	$ 18	$ 44
Interest cost	44	41	89	83
Expected return on plan assets	(83)	(90)	(168)	(182)
Amortization of unrecognized prior service cost (gain)	2	2	4	4
Recognized net (gain) loss	10	(2)	11	(11)
Net periodic benefit cost	(18)	(27)	(46)	(62)
Global | Postemployment
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	2
Interest cost	1	0	1	0
Recognized net (gain) loss	(1)	(1)	(2)	(2)
Total plan benefit (income) expense	1	0	1	0
United States and Canada | Other Nonpension Postretirement
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	4	7	9
Interest cost	10	9	20	18
Expected return on plan assets	(21)	(23)	(42)	(47)
Amortization of unrecognized prior service cost (gain)	(2)	(2)	(4)	(4)
Total plan benefit (income) expense	$ (9)	$ (12)	$ (19)	$ (24)