Employee Benefits - Contributions to Employee Benefit Plans (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended		12 Months Ended
	Sep. 29, 2018	Jun. 30, 2018	Sep. 30, 2017	Apr. 01, 2017	Sep. 29, 2018	Sep. 30, 2017	Dec. 30, 2017
Defined Benefit Plan Disclosure [Line Items]
Restructuring charges	$ 34		$ 1		$ 59	$ 239
Employer contributions to employee benefit plans	5		5		279	33	$ 44
Total current year projected employer contributions	291				291
Employer discretionary contribution amount		$ 250
Pension
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	0		2		266	25	31
Total current year projected employer contributions	274				274
Nonpension postretirement
Defined Benefit Plan Disclosure [Line Items]
Employer contributions to employee benefit plans	5		3		13	8	$ 13
Total current year projected employer contributions	17				17
Employee related costs
Defined Benefit Plan Disclosure [Line Items]
Restructuring charges	$ 17		31		$ 22	$ 166
Employee related costs | Multiemployer Plans
Defined Benefit Plan Disclosure [Line Items]
Restructuring charges				$ 26
Cash Obligation Period				20 years
United States | Pension
Defined Benefit Plan Disclosure [Line Items]
Employer discretionary contribution amount			$ 250