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Commitments and Contingencies - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended | 3 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Sep. 30, 2013 Wellbore Technologies [Member]
Commitment And Contingencies [Line Items] |  |  |  |
Gain from legal settlement included in revenue |  |  |  | $ 102
Rental expense related to operating leases | $ 336 | $ 281 | $ 234 |

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- Details
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Period Type: | duration

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- Definition Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line. + References No definition available. + Details
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- Definition Cash received for the settlement of litigation during the current period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 25 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3536-108585 + Details
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