Commitments and Contingencies (Narrative) (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Commitments and Contingencies
Entity Number of Employees	42,000
Percentage of workforce subject to Collective Bargaining Arrangements	50.00%
Number of Collective Bargaining Agreements	9
Surety Bonds Outstanding
Commitments and Contingencies
Surety bonds outstanding	$ 272
Revolving Credit Facility [Member]
Commitments and Contingencies
Letters of credit issued but undrawn	$ 16
Minimum
Commitments and Contingencies
Period Covered by Collective Bargaining Agreements	3 years
Maximum
Commitments and Contingencies
Period Covered by Collective Bargaining Agreements	5 years
Newport News
Commitments and Contingencies
Number of Collective Bargaining Agreements	4
Ingalls
Commitments and Contingencies
Number of Collective Bargaining Agreements	5
Technical Solutions
Commitments and Contingencies
Entity Number of Employees	25
United Steelworkers [Member] \| Newport News
Commitments and Contingencies
Percentage of workforce subject to Collective Bargaining Arrangements	50.00%

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Commitments and Contingencies [Line Items]

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Total number of collective bargaining agreements.

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The percentage of employees covered by a collective bargaining agreement as of the balance sheet date, when it serves as a benchmark in a concentration of risk calculation.

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- Definition

Description of the significant collective-bargaining arrangements within the range of expiration dates for collective-bargaining arrangements as well as other information to help investors understand the significance of the collective-bargaining agreements and when they expire.

+ References

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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