Segment Information (Unaudited) Sales by Customer Type (Details 2) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Revenue, Major Customer [Line Items]
Sales	$ 9,151	$ 8,884	$ 18,308	$ 17,504
Sales percentage	100.00%	100.00%	100.00%	100.00%
U.S. government(1)
Revenue, Major Customer [Line Items]
Sales	$ 7,861	$ 7,469	$ 15,555	$ 14,563
Sales percentage	86.00%	84.00%	85.00%	83.00%
U.S. government(1) | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,513	$ 2,477	$ 5,054	$ 4,838
Sales percentage	86.00%	85.00%	86.00%	84.00%
U.S. government(1) | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 879	$ 1,305	$ 1,872	$ 2,564
Sales percentage	62.00%	69.00%	63.00%	68.00%
U.S. government(1) | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 1,901	$ 1,776	$ 3,735	$ 3,447
Sales percentage	73.00%	73.00%	72.00%	72.00%
U.S. government(1) | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,568	$ 1,911	$ 4,894	$ 3,714
Sales percentage	93.00%	93.00%	93.00%	93.00%
International(2)
Revenue, Major Customer [Line Items]
Sales	$ 1,209	$ 1,261	$ 2,566	$ 2,596
Sales percentage	13.00%	14.00%	14.00%	15.00%
International(2) | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 351	$ 407	$ 750	$ 851
Sales percentage	12.00%	14.00%	12.00%	15.00%
International(2) | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 335	$ 316	$ 686	$ 656
Sales percentage	23.00%	17.00%	22.00%	18.00%
International(2) | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 419	$ 468	$ 921	$ 951
Sales percentage	16.00%	19.00%	18.00%	20.00%
International(2) | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 104	$ 70	$ 209	$ 138
Sales percentage	4.00%	4.00%	4.00%	3.00%
Other customers
Revenue, Major Customer [Line Items]
Sales	$ 81	$ 154	$ 187	$ 345
Sales percentage	1.00%	2.00%	1.00%	2.00%
Other customers | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 4	$ 12	$ 10	$ 24
Other customers | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 18	$ 85	$ 51	$ 196
Sales percentage	1.00%	4.00%	2.00%	5.00%
Other customers | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 14	$ 18	$ 30	$ 35
Sales percentage	1.00%	1.00%	1.00%	1.00%
Other customers | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 45	$ 39	$ 96	$ 90
Sales percentage	2.00%	2.00%	2.00%	3.00%
Intersegment Sales [Member] | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 45	$ 29	$ 89	$ 55
Sales percentage	2.00%	1.00%	2.00%	1.00%
Intersegment Sales [Member] | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 195	$ 180	$ 380	$ 351
Sales percentage	14.00%	10.00%	13.00%	9.00%
Intersegment Sales [Member] | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 254	$ 184	$ 491	$ 360
Sales percentage	10.00%	7.00%	9.00%	7.00%
Intersegment Sales [Member] | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 31	$ 28	$ 70	$ 54
Sales percentage	1.00%	1.00%	1.00%	1.00%
Operating Segments [Member] | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,913	$ 2,925	$ 5,903	$ 5,768
Sales percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 1,427	$ 1,886	$ 2,989	$ 3,767
Sales percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,588	$ 2,446	$ 5,177	$ 4,793
Sales percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,748	$ 2,048	$ 5,269	$ 3,996
Sales percentage	100.00%	100.00%	100.00%	100.00%