Revenue (Narrative) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
	Jul. 02, 2021	Jul. 02, 2021	Jul. 03, 2020	Jul. 02, 2021	Jul. 03, 2020	Dec. 31, 2020
Revenue from Contract with Customer [Abstract]
Revenue, OTLs and STLs		$ 110	$ 110	$ 219	$ 220
Revenue, remaining performance obligation	$ 3,200	3,200		3,200
Revenue, remaining performance obligation, expected satisfaction in next 12 months, percent	48.00%
Revenue, remaining performance obligation, expected satisfaction in subsequent 12 months, percent	25.00%
Contract with customer, assets, net	$ 94	94		94		$ 65
Contract with customer, liabilities	$ 1,700	$ 1,700		1,700		$ 1,400
Contract with customer, liabilities, revenue recognized				$ 775	$ 419