Postretirement Benefit Plans - Components of Net Periodic Benefit Costs (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 02, 2021	Apr. 03, 2020
Pension
Net periodic benefit income
Service cost	$ 18	$ 16
Interest cost	46	69
Expected return on plan assets	(155)	(158)
Amortization of net actuarial loss	9	2
Amortization of prior service credit	(7)	(7)
Contractual termination benefits	0	1
Total net periodic benefit income	(89)	(77)
Other Benefits
Net periodic benefit income
Service cost	1	0
Interest cost	1	2
Expected return on plan assets	(5)	(5)
Amortization of net actuarial loss	0	0
Amortization of prior service credit	0	0
Contractual termination benefits	0	0
Total net periodic benefit income	$ (3)	$ (3)