Inventoried Costs, Net Inventoried Costs, Net (Narrative) (Details) - USD ($) $ in Millions	Jun. 30, 2017	Dec. 31, 2016
Facility closing \| Avondale Wind Down
Inventory [Line Items]
Restructuring and Related Costs, Capitalized in Inventory	$ 76	$ 94

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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