Segment Information (Unaudited) (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Revenue, Major Customer [Line Items]
Sales	$ 8,456	$ 7,119	$ 16,645	$ 13,854
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%
U.S. government (1)
Revenue, Major Customer [Line Items]
Sales	$ 6,944	$ 5,816	$ 13,701	$ 11,516
Concentration Risk, Percentage	82.00%	82.00%	82.00%	83.00%
U.S. government (1) | Aerospace Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,918	$ 2,799	$ 5,940	$ 5,707
Concentration Risk, Percentage	86.00%	84.00%	86.00%	86.00%
U.S. government (1) | Innovation Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 1,061	$ 265	$ 2,076	$ 265
Concentration Risk, Percentage	71.00%	66.00%	71.00%	66.00%
U.S. government (1) | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,348	$ 2,155	$ 4,515	$ 4,345
Concentration Risk, Percentage	75.00%	75.00%	75.00%	76.00%
U.S. government (1) | Technology Services [Member]
Revenue, Major Customer [Line Items]
Sales	$ 617	$ 597	$ 1,170	$ 1,199
Concentration Risk, Percentage	59.00%	57.00%	58.00%	54.00%
International (2)
Revenue, Major Customer [Line Items]
Sales	$ 1,301	$ 1,125	$ 2,518	$ 1,995
Concentration Risk, Percentage	16.00%	16.00%	15.00%	15.00%
International (2) | Aerospace Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 390	$ 449	$ 784	$ 720
Concentration Risk, Percentage	11.00%	13.00%	11.00%	11.00%
International (2) | Innovation Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 227	$ 92	$ 474	$ 92
Concentration Risk, Percentage	15.00%	23.00%	16.00%	23.00%
International (2) | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 459	$ 391	$ 826	$ 770
Concentration Risk, Percentage	15.00%	14.00%	14.00%	13.00%
International (2) | Technology Services [Member]
Revenue, Major Customer [Line Items]
Sales	$ 225	$ 193	$ 434	$ 413
Concentration Risk, Percentage	22.00%	18.00%	21.00%	19.00%
Other customers
Revenue, Major Customer [Line Items]
Sales	$ 211	$ 178	$ 426	$ 343
Concentration Risk, Percentage	2.00%	2.00%	3.00%	2.00%
Other customers | Aerospace Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 30	$ 38	$ 64	$ 80
Concentration Risk, Percentage	1.00%	1.00%	1.00%	1.00%
Other customers | Innovation Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 118	$ 30	$ 232	$ 30
Concentration Risk, Percentage	8.00%	8.00%	8.00%	8.00%
Other customers | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 39	$ 34	$ 73	$ 64
Concentration Risk, Percentage	1.00%	1.00%	1.00%	1.00%
Other customers | Technology Services [Member]
Revenue, Major Customer [Line Items]
Sales	$ 24	$ 76	$ 57	$ 169
Concentration Risk, Percentage	2.00%	7.00%	3.00%	8.00%
Intersegment sales | Aerospace Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 52	$ 51	$ 98	$ 110
Concentration Risk, Percentage	2.00%	2.00%	2.00%	2.00%
Intersegment sales | Innovation Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 92	$ 13	$ 154	$ 13
Concentration Risk, Percentage	6.00%	3.00%	5.00%	3.00%
Intersegment sales | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 282	$ 294	$ 600	$ 578
Concentration Risk, Percentage	9.00%	10.00%	10.00%	10.00%
Intersegment sales | Technology Services [Member]
Revenue, Major Customer [Line Items]
Sales	$ 178	$ 182	$ 360	$ 411
Concentration Risk, Percentage	17.00%	18.00%	18.00%	19.00%
Operating Segments [Member] | Aerospace Systems [Member]
Revenue, Major Customer [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, Major Customer [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, Major Customer [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, Major Customer [Line Items]
Sales	$ 1,044	$ 1,048	$ 2,021	$ 2,192
Concentration Risk, Percentage	100.00%	100.00%	100.00%	100.00%