Segment Information Sales by Geographic Location (Details 4) - USD ($) $ in Millions	3 Months Ended								7 Months Ended	12 Months Ended
	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2018	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales	$ 8,721	$ 8,475	$ 8,456	$ 8,189	$ 8,156	$ 8,085	$ 7,119	$ 6,735		$ 33,841	$ 30,095	$ 26,004
Concentration Risk, Percentage										100.00%	100.00%	100.00%
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 28,687	$ 25,661	$ 22,552
Concentration Risk, Percentage										85.00%	85.00%	87.00%
Asia/Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 1,836	$ 1,666	$ 1,461
Concentration Risk, Percentage										5.00%	6.00%	5.00%
All Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 3,318	$ 2,768	$ 1,991
Concentration Risk, Percentage										10.00%	9.00%	8.00%
Aerospace Systems [Member] | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 12,150	$ 11,528	$ 10,676
Concentration Risk, Percentage										89.00%	89.00%	90.00%
Aerospace Systems [Member] | Asia/Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 822	$ 705	$ 649
Concentration Risk, Percentage										6.00%	6.00%	6.00%
Aerospace Systems [Member] | All Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 686	$ 666	$ 511
Concentration Risk, Percentage										5.00%	5.00%	4.00%
Aerospace Systems [Member] | Intersegment Sales [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 204	$ 197	$ 295
Aerospace Systems [Member] | Operating Segments [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 13,862	$ 13,096	$ 12,131
Concentration Risk, Percentage										100.00%	100.00%	100.00%
Innovation Systems | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 4,828	$ 2,534	$ 0
Concentration Risk, Percentage										83.00%	80.00%	0.00%
Innovation Systems | Asia/Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 156	$ 151	$ 0
Concentration Risk, Percentage										3.00%	5.00%	0.00%
Innovation Systems | All Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 804	$ 464	$ 0
Concentration Risk, Percentage										14.00%	15.00%	0.00%
Innovation Systems | Intersegment Sales [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 331	$ 127	$ 0
Innovation Systems | Operating Segments [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales									$ 3,300	$ 6,119	$ 3,276	$ 0
Concentration Risk, Percentage										100.00%	100.00%	0.00%
Mission Systems [Member] | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 9,196	$ 8,917	$ 8,976
Concentration Risk, Percentage										83.00%	85.00%	86.00%
Mission Systems [Member] | Asia/Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 676	$ 659	$ 671
Concentration Risk, Percentage										6.00%	6.00%	6.00%
Mission Systems [Member] | All Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 1,164	$ 988	$ 869
Concentration Risk, Percentage										11.00%	9.00%	8.00%
Mission Systems [Member] | Intersegment Sales [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 1,227	$ 1,145	$ 954
Mission Systems [Member] | Operating Segments [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 12,263	$ 11,709	$ 11,470
Concentration Risk, Percentage										100.00%	100.00%	100.00%
Technology Services [Member] | United States
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 2,513	$ 2,682	$ 2,900
Concentration Risk, Percentage										75.00%	77.00%	79.00%
Technology Services [Member] | Asia/Pacific
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 182	$ 151	$ 141
Concentration Risk, Percentage										5.00%	4.00%	4.00%
Technology Services [Member] | All Other
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 664	$ 650	$ 611
Concentration Risk, Percentage										20.00%	19.00%	17.00%
Technology Services [Member] | Intersegment Sales [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 751	$ 814	$ 1,035
Technology Services [Member] | Operating Segments [Member]
Revenues from External Customers and Long-Lived Assets [Line Items]
Sales										$ 4,110	$ 4,297	$ 4,687
Concentration Risk, Percentage										100.00%	100.00%	100.00%