Revenue - Impact of Adjustments in Contract Estimates (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		9 Months Ended
	Sep. 29, 2019	Sep. 30, 2018	Sep. 29, 2019	Sep. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue	$ 9,761	$ 9,094	$ 28,577	$ 25,815
Operating earnings	$ 1,216	$ 1,135	$ 3,320	$ 3,231
Diluted earnings per share (in dollars per share)	$ 3.14	$ 2.85	$ 8.47	$ 8.12
Accounting Standards Update 2014-09
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Revenue	$ 95	$ 96	$ 263	$ 302
Operating earnings	$ 81	$ 103	$ 220	$ 283
Diluted earnings per share (in dollars per share)	$ 0.22	$ 0.27	$ 0.60	$ 0.75