Revenue (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended
	Apr. 02, 2021	Apr. 02, 2021	Apr. 03, 2020	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue, OTLs and STLs		$ 109	$ 110
Revenue, remaining performance obligation	$ 2,900	2,900
Revenue, remaining performance obligation, expected satisfaction in next 12 months, percent	47.00%
Revenue, remaining performance obligation, expected satisfaction in subsequent 12 months, percent	25.00%
Contract with customer, asset, net	$ 77	77		$ 65
Contract with customer, liability	$ 1,500	1,500		$ 1,400
Contract with customer, liability, revenue recognized		$ 520	$ 268