Other Financial Data (Other Current Assets) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Other Current Assets [Abstract]
Available-for-sale securities	$ 46	$ 438
Costs and earnings in excess of billings	495	374
Tax-related refunds receivable	90	44
Other	124	98
Other current assets	$ 755	$ 954

No definition available.

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- Definition

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

+ References

No definition available.

+ Details

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- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 25
-Paragraph 1
-Subparagraph (b)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562

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- Definition

Amount of receivable reflecting the cost incurred on uncompleted contracts in excess of related billings which is expected to be collected within one year or the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 605
-SubTopic 35
-Section 45
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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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- Definition

Amount of current assets classified as other.

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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

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