Avondale (Narrative) (Details) $ in Millions	9 Months Ended
Sep. 30, 2018 USD ($)
Restructuring Cost and Reserve
Restructuring and Related Costs, Allowable	$ 251
Facility closing \| Avondale Wind Down
Restructuring Cost and Reserve
Assets held for sale	$ 41
Subsequent Event [Member] \| Facility closing \| Avondale Wind Down
Restructuring Cost and Reserve
Financing receivable, contractual term	9 years
Gains (Losses) on Sales of Assets	$ 7

Contractual term of the financing receivable.

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- Definition

The net amount allowable under government contracts for the specified restructuring costs.

+ References

No definition available.

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- Definition

The net gain (loss) resulting from sales and other disposals of other real estate owned, increases (decreases) in the valuation allowance for foreclosed real estate, and write-downs of other real estate owned after acquisition or physical possession.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

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- Definition

Carrying amount as of the balance sheet date of investments in land and buildings held for sale, excluding real estate considered to be inventory of the entity.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.1(f))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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- Definition

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.

+ References

No definition available.

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