Employee Benefits - Components of Plan Benefit Expense (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 03, 2021	Jun. 27, 2020	Jul. 03, 2021	Jun. 27, 2020
Defined Benefit Plan Disclosure [Line Items]
Curtailment (gain) loss		$ (7)
Pension | Global Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 9	9	$ 18	$ 18
Interest cost	25	33	50	68
Expected return on plan assets	(77)	(85)	(155)	(170)
Amortization of unrecognized prior service cost (gain)	2	2	4	4
Recognized net (gain) loss	(11)	43	(20)	57
Net periodic benefit cost	(52)	2	(103)	(23)
Curtailment (gain) loss	0	(7)	0	(7)
Total plan benefit (income) expense	(52)	(5)	(103)	(30)
Other Nonpension Postretirement | U.S. and Canada
Defined Benefit Plan Disclosure [Line Items]
Service cost	3	4	6	7
Interest cost	5	8	10	16
Expected return on plan assets	(23)	(23)	(46)	(46)
Amortization of unrecognized prior service cost (gain)	(2)	(3)	(4)	(5)
Total plan benefit (income) expense	(17)	(14)	(34)	(28)
Postemployment | Global Plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	2	2
Recognized net (gain) loss	(1)	(1)	(2)	(2)
Total plan benefit (income) expense	$ 0	$ 0	$ 0	$ 0