Contract Assets and Contract Liabilities - Components of Net Contract Assets (Liabilities) (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
	Jun. 29, 2018	Jun. 29, 2018	Jan. 01, 2018	Dec. 31, 2017
Revenue from Contract with Customer [Abstract]
Contract assets	$ 1,611	$ 1,611	$ 1,349	$ 0
Contract liabilities — current	(554)	(554)	(565)	0
Contract liabilities — non-current	(33)	(33)	(28)	$ 0
Net contract assets (liabilities)	1,024	1,024	$ 756
Increase in contract assets	262
Increase in contract liability	$ (6)
Revenue recognized related to contract liabilities		$ 351