Defined Benefit Plans (Components of Net Periodic Benefit Cost of Other Postretirement Benefit Pension Pans) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 02, 2021	Jul. 03, 2020	Jul. 02, 2021	Jul. 03, 2020
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ (11)	$ (11)	$ (22)	$ (17)
Net periodic cost	0	(6)	0	(7)
Other postretirement benefit plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	0	0	0	0
Interest cost	0	(1)	(1)	(2)
Amortization of actuarial loss	(1)	0	(1)	0
Amortization of prior service credit	0	1	1	1
Net periodic cost	$ (1)	$ 0	$ (1)	$ (1)