Accumulated Other Comprehensive Loss and Other Comprehensive Income (Loss) - Before and after-tax components of other comprehensive income (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Pension and postretirement benefits adjustments, pre-tax:
Amortization of net actuarial loss, pre-tax	$ 34	$ 26	$ 68	$ 52
Amortization of prior service cost (credit), pre-tax	2	(2)	4	(4)
Unrealized gains, pre-tax				7
Pension and postretirement benefits adjustments, net, pre-tax	36	24	72	55
Deferred gains on hedge contracts, pre-tax:
Current deferrals, pre-tax	2	(2)	5	20
Reclassification adjustments, pre-tax	4	8	6	15
Deferred gains on hedge contracts, net, pre-tax	6	6	11	35
Foreign currency translation adjustments, pre-tax	39	(14)	60	11
Other comprehensive income (loss), pre-tax	81	16	143	101
Pension and postretirement benefits adjustments, tax:
Amortization of net actuarial loss, tax	(12)	(10)	(24)	(19)
Amortization of prior service cost (credit), tax	(1)	1	(1)	2
Unrealized gains, tax				(2)
Pension and postretirement benefits adjustments, net, tax	(13)	(9)	(25)	(19)
Deferred gains on hedge contracts, tax:
Current deferrals, tax	(1)		(2)	(6)
Reclassification adjustments, tax	(1)	(2)	(1)	(4)
Deferred gains on hedge contracts, net, tax	(2)	(2)	(3)	(10)
Foreign currency translation adjustments, tax	3	(6)	4	(7)
Other comprehensive income (loss), tax	(12)	(17)	(24)	(36)
Pension and postretirement benefits adjustments, after-tax:
Amortization of net actuarial loss, after-tax	22	16	44	33
Amortization of prior service cost (credit), after-tax	1	(1)	3	(2)
Unrealized gains, after-tax				5
Pension and postretirement benefits adjustments, net, after-tax	23	15	47	36
Deferred gains on hedge contracts, after-tax:
Current deferrals, after-tax	1	(2)	3	14
Reclassification adjustments, after-tax	3	6	5	11
Deferred gains on hedge contracts, net, after-tax	4	4	8	25
Foreign currency translation adjustments, after-tax	42	(20)	64	4
Other comprehensive income (loss)	$ 69	$ (1)	$ 119	$ 65