Change in Carrying Amount of Goodwill (Table) (Details) $ in Millions	6 Months Ended
Jun. 30, 2020 USD ($)
Goodwill [Roll Forward]
Goodwill beginning balance	$ 1,373
Goodwill, acquisitions	310
Goodwill, Purchase Accounting Adjustments	(107)
Goodwill ending balance	1,576
Ingalls
Goodwill [Roll Forward]
Goodwill beginning balance	175
Goodwill ending balance	175
Newport News
Goodwill [Roll Forward]
Goodwill beginning balance	721
Goodwill ending balance	721
Technical Solutions
Goodwill [Roll Forward]
Goodwill beginning balance	477
Goodwill, acquisitions	310
Goodwill, Purchase Accounting Adjustments	(107)
Goodwill ending balance	$ 680

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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