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Summary of Significant Accounting Policies (Details 1) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010
Identified intangible assets identified by segment
Beginning Balance	$ 4,103	$ 4,052
Additions to intangible assets	273	299
Amortization	(276)	(245)
Currency translation adjustments and other	(27)	(3)
Ending Balance	4,073	4,103
Rig Technology [Member]
Identified intangible assets identified by segment
Beginning Balance	666	416
Additions to intangible assets	70	291
Amortization	(60)	(38)
Currency translation adjustments and other	(22)	(3)
Ending Balance	654	666
Petroleum Services & Supplies [Member]
Identified intangible assets identified by segment
Beginning Balance	3,432	3,630
Additions to intangible assets	176	8
Amortization	(213)	(206)
Currency translation adjustments and other	(4)
Ending Balance	3,391	3,432
Distribution and Transmission [Member]
Identified intangible assets identified by segment
Beginning Balance	5	6
Additions to intangible assets	27
Amortization	(3)	(1)
Currency translation adjustments and other	(1)
Ending Balance	$ 28	$ 5

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- Definition

Intangible Assets Acquired During Period.

+ References

No definition available.

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- Definition

Intangible Assets Translation And Purchase Accounting Adjustments.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(2)

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275



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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 45

-Subparagraph a(2)

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6943989&loc=d3e3602-108585



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 45

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274

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- Definition

Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

+ References

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 142

-Paragraph 42, 45

-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.



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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph ((a)(1),(b))

-URI http://asc.fasb.org/extlink&oid=6905858&loc=d3e16323-109275



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-Name Accounting Standards Codification

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