Shareholders' Equity - Accumulated Other Comprehensive Loss and Other Comprehensive Income (Loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 03, 2021	Apr. 04, 2020
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning of period	$ (1,739)
End of period	(1,723)
Accumulated Other Comprehensive Loss
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning of period	(1,739)	$ (1,847)
Other comprehensive loss before reclassifications	(28)	(48)
Reclassified from Accumulated other comprehensive loss	44	36
End of period	(1,723)	(1,859)
Pensions and Postretirement Benefits Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning of period	(1,780)	(1,811)
Other comprehensive loss before reclassifications	0	0
Reclassified from Accumulated other comprehensive loss	30	37
End of period	(1,750)	(1,774)
Foreign Currency Translation Adjustments
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning of period	42	(36)
Other comprehensive loss before reclassifications	(32)	(40)
Reclassified from Accumulated other comprehensive loss	14	0
End of period	24	(76)
Deferred Gains (Losses) on Hedge Contracts
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Beginning of period	(1)	0
Other comprehensive loss before reclassifications	4	(8)
Reclassified from Accumulated other comprehensive loss	0	(1)
End of period	$ 3	$ (9)