Revenue - Impact of Adjustments in Contract Estimates (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended		12 Months Ended
	Jul. 02, 2017	Jul. 03, 2016	Jul. 02, 2017	Jul. 03, 2016	Dec. 31, 2016
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue			$ 27,400		$ 25,543
Operating earnings	$ 1,056	$ 1,027	$ 2,091	$ 1,951
Diluted earnings per share			$ 4.94	$ 4.35
Difference between Revenue Guidance in Effect before and after Topic 606 | Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue	90	55	$ 162	$ 123
Operating earnings	$ 121	$ 59	$ 171	$ 117
Diluted earnings per share	$ 0.26	$ 0.12	$ 0.36	$ 0.24