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Goodwill and Intangible Assets - Goodwill Identified by Segment (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | $ 6,227 | $ 6,067
Goodwill acquired and adjusted during period | 102 | 89
Currency translation adjustments | (65) | 71
Goodwill, Ending Balance | 6,264 | 6,227
Wellbore Technologies [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 2,956 | 2,874
Goodwill acquired and adjusted during period | 64 | 37
Currency translation adjustments | (9) | 45
Goodwill, Ending Balance | 3,011 | 2,956
Completion & Production Solutions [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 2,122 | 2,058
Goodwill acquired and adjusted during period | (33) | 41
Currency translation adjustments | (48) | 23
Goodwill, Ending Balance | 2,041 | 2,122
Rig Technologies [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 1,149 | 1,135
Goodwill acquired and adjusted during period | 71 | 11
Currency translation adjustments | (8) | 3
Goodwill, Ending Balance | $ 1,212 | $ 1,149

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- Definition Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266 + Details
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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- Definition Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267 + Details
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