Segment Information (Unaudited) Reconciliation to Consolidated Operating Income (Details 1) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) segment	Mar. 31, 2019 USD ($)
Segment Reporting Information [Line Items]
Number of reportable segments | segment	4
Sales	$ 8,620	$ 8,189
Operating income	934	936
Operating Segments [Member]
Segment Reporting Information [Line Items]
Operating income	953	967
Operating Segments [Member] | Aeronautics Systems [Member]
Segment Reporting Information [Line Items]
Sales	2,843	2,818
Operating income	259	308
Operating Segments [Member] | Defense Systems [Member]
Segment Reporting Information [Line Items]
Sales	1,881	1,768
Operating income	196	202
Operating Segments [Member] | Mission Systems [Member]
Segment Reporting Information [Line Items]
Sales	2,347	2,210
Operating income	348	319
Operating Segments [Member] | Space Systems [Member]
Segment Reporting Information [Line Items]
Sales	1,948	1,801
Operating income	199	188
Intersegment sales
Segment Reporting Information [Line Items]
Sales	(399)	(408)
Operating income	(49)	(50)
Segment Reconciling Items [Member]
Segment Reporting Information [Line Items]
Net FAS (service)/ CAS pension adjustment	105	108
Corporate, Non-Segment [Member]
Segment Reporting Information [Line Items]
Operating income	$ (124)	$ (139)