Segment Information (Unaudited) Sales by Customer Type (Details 2) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Revenue, Major Customer [Line Items]
Sales	$ 8,720	$ 9,083	$ 27,028	$ 26,587
Sales percentage	100.00%	100.00%	100.00%	100.00%
U.S. government(1)
Revenue, Major Customer [Line Items]
Sales	$ 7,452	$ 7,659	$ 23,007	$ 22,222
Sales percentage	85.00%	84.00%	85.00%	84.00%
U.S. government(1) | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,312	$ 2,491	$ 7,366	$ 7,329
Sales percentage	85.00%	85.00%	85.00%	84.00%
U.S. government(1) | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 877	$ 1,264	$ 2,749	$ 3,828
Sales percentage	62.00%	68.00%	63.00%	68.00%
U.S. government(1) | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 1,756	$ 1,884	$ 5,491	$ 5,331
Sales percentage	72.00%	74.00%	71.00%	73.00%
U.S. government(1) | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,507	$ 2,020	$ 7,401	$ 5,734
Sales percentage	94.00%	92.00%	93.00%	93.00%
International(2)
Revenue, Major Customer [Line Items]
Sales	$ 1,185	$ 1,243	$ 3,751	$ 3,839
Sales percentage	14.00%	14.00%	14.00%	14.00%
International(2) | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 360	$ 382	$ 1,110	$ 1,233
Sales percentage	13.00%	13.00%	13.00%	14.00%
International(2) | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 316	$ 307	$ 1,002	$ 963
Sales percentage	22.00%	17.00%	23.00%	17.00%
International(2) | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 417	$ 455	$ 1,338	$ 1,406
Sales percentage	17.00%	18.00%	18.00%	19.00%
International(2) | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 92	$ 99	$ 301	$ 237
Sales percentage	3.00%	5.00%	4.00%	4.00%
Other customers
Revenue, Major Customer [Line Items]
Sales	$ 83	$ 181	$ 270	$ 526
Sales percentage	1.00%	2.00%	1.00%	2.00%
Other customers | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 5	$ 11	$ 15	$ 35
Sales percentage	0.00%	1.00%	0.00%	1.00%
Other customers | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 10	$ 97	$ 61	$ 293
Sales percentage	1.00%	5.00%	1.00%	5.00%
Other customers | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 19	$ 19	$ 49	$ 54
Sales percentage	1.00%	1.00%	1.00%	1.00%
Other customers | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 49	$ 54	$ 145	$ 144
Sales percentage	2.00%	2.00%	2.00%	2.00%
Intersegment Sales [Member] | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 48	$ 30	$ 137	$ 85
Sales percentage	2.00%	1.00%	2.00%	1.00%
Intersegment Sales [Member] | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 206	$ 191	$ 586	$ 542
Sales percentage	15.00%	10.00%	13.00%	10.00%
Intersegment Sales [Member] | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 244	$ 193	$ 735	$ 553
Sales percentage	10.00%	7.00%	10.00%	7.00%
Intersegment Sales [Member] | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 33	$ 25	$ 103	$ 79
Sales percentage	1.00%	1.00%	1.00%	1.00%
Operating Segments [Member] | Aeronautics Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,725	$ 2,914	$ 8,628	$ 8,682
Sales percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Defense Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 1,409	$ 1,859	$ 4,398	$ 5,626
Sales percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Mission Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,436	$ 2,551	$ 7,613	$ 7,344
Sales percentage	100.00%	100.00%	100.00%	100.00%
Operating Segments [Member] | Space Systems [Member]
Revenue, Major Customer [Line Items]
Sales	$ 2,681	$ 2,198	$ 7,950	$ 6,194
Sales percentage	100.00%	100.00%	100.00%	100.00%