Employee Benefits - Contributions to Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 26, 2020	Sep. 28, 2019	Sep. 26, 2020	Sep. 28, 2019	Dec. 28, 2019
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	$ 7	$ 7	$ 19	$ 19	$ 28
Total current year projected employer contributions	26		26
Global Plans | Pension
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	1	2	4	6	10
Total current year projected employer contributions	7		7
U.S. and Canada | Nonpension postretirement
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	6	$ 5	15	$ 13	$ 18
Total current year projected employer contributions	$ 19		$ 19