Shareholders' Equity - Before and after-tax components of other comprehensive income (loss) (Details) - USD ($) $ in Millions	3 Months Ended
	Apr. 04, 2020	Mar. 30, 2019
Pension and postretirement benefits adjustments, pre-tax:
Amortization of net actuarial loss, pre-tax	$ 46	$ 25
Amortization of prior service cost, pre-tax	2	1
Pension and postretirement benefits adjustments, net, pre-tax	48	26
Deferred gains (losses) on hedge contracts, pre-tax:
Current deferrals, pre-tax	(9)	4
Reclassification adjustments, pre-tax	(1)	(1)
Deferred gains (losses) on hedge contracts, net, pre-tax	(10)	3
Foreign currency translation adjustments, pre-tax	(37)	1
Other comprehensive income (loss), pre-tax	1	30
Pension and postretirement benefits adjustments, tax:
Amortization of net actuarial loss, tax	(10)	(5)
Amortization of prior service cost, tax	(1)
Pension and postretirement benefits adjustments, net, tax	(11)	(5)
Deferred gains (losses) on hedge contracts, tax:
Current deferrals, tax	1	(1)
Deferred gains (losses) on hedge contracts, net, tax	1	(1)
Foreign currency translation adjustments, tax	(3)	2
Other comprehensive income (loss), tax	(13)	(4)
Pension and postretirement benefits adjustments, after-tax:
Amortization of net actuarial loss, after-tax	36	20
Amortization of prior service cost, after-tax	1	1
Pension and postretirement benefits adjustments, net, after-tax	37	21
Deferred gains (losses) on hedge contracts, after-tax:
Current deferrals, after-tax	(8)	3
Reclassification adjustments, after-tax	(1)	(1)
Deferred gains (losses) on hedge contracts, net, after-tax	(9)	2
Foreign currency translation adjustments, after-tax	(40)	3
Other comprehensive income (losses)	$ (12)	$ 26