Revenue (Table) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Disaggregation of Revenue [Line Items]
Sales and service revenues	$ 2,314	$ 2,219	$ 6,604	$ 6,487
Firm fixed-price
Disaggregation of Revenue [Line Items]
Sales and service revenues	72	89	227	225
Fixed-price incentive
Disaggregation of Revenue [Line Items]
Sales and service revenues	1,288	1,097	3,477	3,079
Cost-type
Disaggregation of Revenue [Line Items]
Sales and service revenues	849	913	2,580	2,874
Time-and-materials
Disaggregation of Revenue [Line Items]
Sales and service revenues	105	120	320	309
Federal
Disaggregation of Revenue [Line Items]
Sales and service revenues	2,248	2,141	6,406	6,272
Commercial
Disaggregation of Revenue [Line Items]
Sales and service revenues	66	78	197	215
State and local government agencies
Disaggregation of Revenue [Line Items]
Sales and service revenues			1
Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	1,699	1,545	4,743	4,555
Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	615	674	1,861	1,932
Ingalls
Disaggregation of Revenue [Line Items]
Sales and service revenues	675	647	1,926	1,853
Intersegment		1	2	2
Ingalls | Amphibious assault ships
Disaggregation of Revenue [Line Items]
Sales and service revenues	338	349	1,013	971
Ingalls | Surface combatants and coast guard cutters
Disaggregation of Revenue [Line Items]
Sales and service revenues	335	294	909	875
Ingalls | Other programs
Disaggregation of Revenue [Line Items]
Sales and service revenues	2	4	4	7
Ingalls | Firm fixed-price
Disaggregation of Revenue [Line Items]
Sales and service revenues	9	21	40	61
Ingalls | Fixed-price incentive
Disaggregation of Revenue [Line Items]
Sales and service revenues	606	519	1,664	1,487
Ingalls | Cost-type
Disaggregation of Revenue [Line Items]
Sales and service revenues	60	106	220	303
Ingalls | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues		1	2	2
Ingalls | Federal
Disaggregation of Revenue [Line Items]
Sales and service revenues	675	646	1,924	1,851
Ingalls | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues		1	2	2
Ingalls | Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	623	584	1,765	1,678
Ingalls | Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	52	62	159	173
Newport News
Disaggregation of Revenue [Line Items]
Sales and service revenues	1,358	1,274	3,821	3,832
Intersegment	3	1	7	4
Newport News | Aircraft carriers
Disaggregation of Revenue [Line Items]
Sales and service revenues	733	706	2,087	2,166
Newport News | Submarines
Disaggregation of Revenue [Line Items]
Sales and service revenues	436	390	1,177	1,121
Newport News | Other programs
Disaggregation of Revenue [Line Items]
Sales and service revenues	189	178	557	545
Newport News | Firm fixed-price
Disaggregation of Revenue [Line Items]
Sales and service revenues	5	4	8	8
Newport News | Fixed-price incentive
Disaggregation of Revenue [Line Items]
Sales and service revenues	682	578	1,813	1,591
Newport News | Cost-type
Disaggregation of Revenue [Line Items]
Sales and service revenues	668	691	1,993	2,229
Newport News | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues	3	1	7	4
Newport News | Federal
Disaggregation of Revenue [Line Items]
Sales and service revenues	1,355	1,262	3,813	3,792
Newport News | Commercial
Disaggregation of Revenue [Line Items]
Sales and service revenues		11	1	36
Newport News | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues	3	1	7	4
Newport News | Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	1,054	962	2,926	2,877
Newport News | Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	301	311	888	951
Technical Solutions
Disaggregation of Revenue [Line Items]
Sales and service revenues	320	326	957	887
Intersegment	36	26	91	79
Technical Solutions | Government and energy services
Disaggregation of Revenue [Line Items]
Sales and service revenues	259	263	772	719
Technical Solutions | Oil and gas services
Disaggregation of Revenue [Line Items]
Sales and service revenues	61	63	185	168
Technical Solutions | Firm fixed-price
Disaggregation of Revenue [Line Items]
Sales and service revenues	58	64	179	156
Technical Solutions | Fixed-price incentive
Disaggregation of Revenue [Line Items]
Sales and service revenues				1
Technical Solutions | Cost-type
Disaggregation of Revenue [Line Items]
Sales and service revenues	121	116	367	342
Technical Solutions | Time-and-materials
Disaggregation of Revenue [Line Items]
Sales and service revenues	105	120	320	309
Technical Solutions | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues	36	26	91	79
Technical Solutions | Federal
Disaggregation of Revenue [Line Items]
Sales and service revenues	218	233	669	629
Technical Solutions | Commercial
Disaggregation of Revenue [Line Items]
Sales and service revenues	66	67	196	179
Technical Solutions | State and local government agencies
Disaggregation of Revenue [Line Items]
Sales and service revenues			1
Technical Solutions | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues	36	26	91	79
Technical Solutions | Product [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	22	(1)	52
Technical Solutions | Service [Member]
Disaggregation of Revenue [Line Items]
Sales and service revenues	262	301	814	808
Intersegment Elimination
Disaggregation of Revenue [Line Items]
Sales and service revenues	(39)	(28)	(100)	(85)
Intersegment	(39)	(28)	(100)	(85)
Intersegment Elimination | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues	(39)	(28)	(100)	(85)
Intersegment Elimination | Intersegment
Disaggregation of Revenue [Line Items]
Sales and service revenues	$ (39)	$ (28)	$ (100)	$ (85)