Retirement and Other Employee Benefits - Pension and Postretirement Health Care Benefits (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 27, 2020	Jun. 29, 2019	Jun. 27, 2020	Jun. 29, 2019
Postretirement Health Care Benefits Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 0	$ 0	$ 0	$ 0
Interest cost	0	1	1	1
Expected return on plan assets	(3)	(3)	(5)	(5)
Amortization of
Unrecognized net loss	1	1	2	2
Unrecognized prior service benefit	(3)	(4)	(7)	(7)
Net periodic pension benefits	(5)	(5)	(9)	(9)
U.S. | Pension Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	36	51	72	102
Expected return on plan assets	(56)	(69)	(112)	(138)
Amortization of
Unrecognized net loss	15	12	29	23
Unrecognized prior service benefit	0	0	0	0
Net periodic pension benefits	(5)	(6)	(11)	(13)
Non-U.S. | Pension Benefit Plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	1	1	1	2
Interest cost	7	10	14	20
Expected return on plan assets	(20)	(21)	(42)	(42)
Amortization of
Unrecognized net loss	3	4	7	8
Unrecognized prior service benefit	(1)	0	(1)	0
Net periodic pension benefits	$ (10)	$ (6)	$ (21)	$ (12)