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Summary of Significant Accounting Policies - Identified Intangible Assets Identified by Segment (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
--- | ---
Dec. 31, 2012 | Dec. 31, 2011
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | $ 4,073 | $ 4,103
Additions to intangible assets | 981 | 273
Amortization | (305) | (276)
Currency translation adjustments and other | (6) | (27)
Ending Balance | 4,743 | 4,073
Rig Technology [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 654 | 666
Additions to intangible assets | 545 | 70
Amortization | (76) | (60)
Currency translation adjustments and other | (11) | (22)
Ending Balance | 1,112 | 654
Petroleum Services & Supplies [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 3,391 | 3,432
Additions to intangible assets | 380 | 176
Amortization | (224) | (213)
Currency translation adjustments and other | 3 | (4)
Ending Balance | 3,550 | 3,391
Distribution & Transmission [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 28 | 5
Additions to intangible assets | 56 | 27
Amortization | (5) | (3)
Currency translation adjustments and other | 2 | (1)
Ending Balance | $ 81 | $ 28

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- Definition Intangible Assets Translation And Purchase Accounting Adjustments. + References No definition available. + Details
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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 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of Financial Accounting Standard (FAS) -Number 142 -Paragraph 45 -Subparagraph a(2) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 2: 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 3: 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 Reference 4: 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=7658586&loc=d3e16323-109275 + Details
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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 Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16212-109274 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=7658586&loc=d3e16323-109275 Reference 3: 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. + Details
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