Segment Information (Unaudited) (Details 3) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue, Contract Type [Line Items]
Sales	$ 8,456	$ 7,119	$ 16,645	$ 13,854
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
Cost-type [Member]
Revenue, Contract Type [Line Items]
Sales	$ 4,112	$ 3,625	$ 8,188	$ 7,243
Concentration Risk, Percentage	49.00%	51.00%	49.00%	52.00%
Cost-type [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,979	$ 1,934	$ 3,981	$ 3,836
Concentration Risk, Percentage	59.00%	59.00%	59.00%	59.00%
Cost-type [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 405	$ 99	$ 813	$ 99
Concentration Risk, Percentage	29.00%	26.00%	29.00%	26.00%
Cost-type [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,316	$ 1,207	$ 2,590	$ 2,486
Concentration Risk, Percentage	46.00%	47.00%	48.00%	48.00%
Cost-type [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	$ 412	$ 385	$ 804	$ 822
Concentration Risk, Percentage	48.00%	44.00%	48.00%	46.00%
Fixed-price [Member]
Revenue, Contract Type [Line Items]
Sales	$ 4,344	$ 3,494	$ 8,457	$ 6,611
Concentration Risk, Percentage	51.00%	49.00%	51.00%	48.00%
Fixed-price [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,359	$ 1,352	$ 2,807	$ 2,671
Concentration Risk, Percentage	41.00%	41.00%	41.00%	41.00%
Fixed-price [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,001	$ 288	$ 1,969	$ 288
Concentration Risk, Percentage	71.00%	74.00%	71.00%	74.00%
Fixed-price [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,530	$ 1,373	$ 2,824	$ 2,693
Concentration Risk, Percentage	54.00%	53.00%	52.00%	52.00%
Fixed-price [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	$ 454	$ 481	$ 857	$ 959
Concentration Risk, Percentage	52.00%	56.00%	52.00%	54.00%
Intersegment sales | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 52	$ 51	$ 98	$ 110
Intersegment sales | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	92	13	154	13
Intersegment sales | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	282	294	600	578
Intersegment sales | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	178	182	360	411
Operating Segments [Member] | Aerospace Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 3,390	$ 3,337	$ 6,886	$ 6,617
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Innovation Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,498	$ 400	$ 2,936	$ 400
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Mission Systems [Member]
Revenue, Contract Type [Line Items]
Sales	$ 3,128	$ 2,874	$ 6,014	$ 5,757
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Technology Services [Member]
Revenue, Contract Type [Line Items]
Sales	$ 1,044	$ 1,048	$ 2,021	$ 2,192
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%