Other Financial Data (Other Current Assets) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012	Dec. 31, 2011
Other Current Assets [Abstract]
Costs and earnings in excess of billings	$ 339	$ 302
Contract-related deferred costs	150	142
Tax-related refunds receivable	86	85
Other	197	147
Other current assets	$ 772	$ 676

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This element represents other current assets other than specified in taxonomy.

+ References

No definition available.

+ Details

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- Definition

The amount of deferred costs by type of cost for long-term contracts and programs as of the balance sheet date. Examples include initial tooling and deferred production costs.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 5

-Section 02

-Paragraph 6

-Subparagraph d(1)

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.6(d)(i))

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

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- Definition

Amount included in cost of uncompleted contracts in excess of related billings, or unbilled accounts receivable, which is expected to be collected within a year within one year (or one operating cycle, if longer) from the date of the balance sheet.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 35

-Section 45

-Paragraph 4

-URI http://asc.fasb.org/extlink&oid=6802688&loc=d3e57795-111642

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-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)

-Number 210

-Section 02

-Paragraph 3

-Subparagraph c(3)

-Article 5

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Research Bulletin (ARB)

-Number 45

-Paragraph 12

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 35

-Section 45

-Paragraph 5

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- Definition

Aggregate carrying amount, as of the balance sheet date, of current assets not separately disclosed in the balance sheet. Current assets are expected to be realized or consumed within one year (or the normal operating cycle, if longer).

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 8

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

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- Definition

Carrying amount as of the balance sheet date of value added taxes due either from customers arising from sales on credit terms, or as previously overpaid to tax authorities.

+ References

+ Details

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