Revenue (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Jul. 03, 2020	Jul. 03, 2020	Jun. 28, 2019	Jul. 03, 2020	Jun. 28, 2019	Dec. 31, 2019
Revenue from Contract with Customer [Abstract]
Revenue, OTLs and STLs		$ 110	$ 106	$ 220	$ 212
Revenue, remaining performance obligation	$ 2,600	2,600		2,600
Revenue, remaining performance obligation, expected satisfaction in next 12 months, percent	51.00%
Revenue, remaining performance obligation, expected satisfaction in subsequent 12 months, percent	22.00%
Contract with customer, asset, net	$ 87	87		87		$ 77
Contract with customer, liability	$ 1,200	$ 1,200		1,200		$ 806
Contract with customer, liability, revenue recognized				$ 419	$ 403