Accounts Receivable (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Accounts Receivable [Line Items]
Total accounts receivable	$ 4,050,000,000us-gaap_AccountsReceivableNetCurrent	$ 4,370,000,000us-gaap_AccountsReceivableNetCurrent
Non-U.S. Government
Accounts Receivable [Line Items]
Total accounts receivable	2,529,000,000	2,767,000,000
Receivables related to long-term production programs	2,300,000,000
Receivables related to long-term production programs, net of customer advances	21,000,000
U.S. Government
Accounts Receivable [Line Items]
Total accounts receivable	822,000,000	951,000,000
Commercial
Accounts Receivable [Line Items]
Total accounts receivable	$ 699,000,000	$ 652,000,000

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Receivables, Long-term Contracts or Programs, Net of Customer Advances

+ References

No definition available.

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- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ 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 210.5-02.3-4)

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph a(1)

-Article 5

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 4

-Article 5

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- Definition

Amount to be collected within one year of the balance sheet date (or one operating cycle, if longer) from customers in accordance with the contractual provisions of long-term contracts or programs including amounts billed and unbilled as of the balance sheet date.

+ 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))

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

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c

-Article 5

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