Contracts in Process - Components of Contracts in Process (Detail) (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Components of contracts in process
Unbilled contract receivables, gross	$ 2,280lll_UnbilledContractReceivablesGross	$ 2,493lll_UnbilledContractReceivablesGross
Unliquidated progress payments	(887)	(1,008)
Unbilled contract receivables, net	1,393us-gaap_UnbilledContractsReceivable	1,485us-gaap_UnbilledContractsReceivable
Inventoried contract costs, gross	997	1,037
Unliquidated progress payments	(95)	(80)
Inventoried contract costs, net	902	957
Total contracts in process	$ 2,295	$ 2,442

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Amount before progress payments for unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be gross amounts associated with contracts or programs where the recognized revenue for performance there under exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ References

No definition available.

+ Details

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- Definition

Amount of advances received from customers under long-term contracts which have been offset against Unbilled Contract Receivables at the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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- Definition

Amount before valuation and LIFO reserves, and progress payments, of inventory associated with long-term contracts, expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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- Definition

Carrying amount (lower of cost or market) of inventories less all valuation, other allowances, and progress payments or customer advances received on long-term contracts or programs. Excludes noncurrent inventory balances (expected to remain on hand past one year or one operating cycle, if longer).

+ References

No definition available.

+ Details

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Amount of advances received from customers under long-term contracts which have been offset against inventories accounts at the balance sheet date.

+ References

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- Definition

Unbilled amounts due for services rendered or to be rendered, actions taken or to be taken, or a promise to refrain from taking certain actions in accordance with the terms of a legally binding agreement between the entity and, at a minimum, one other party. An example would be amounts associated with contracts or programs where the recognized revenue for performance thereunder exceeds the amounts billed under the terms thereof as of the date of the balance sheet.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.3(c)(3))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher SEC

-Name Regulation S-X (SX)

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-Publisher FASB

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