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Summary of Significant Accounting Policies - Goodwill Identified by Segment (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | $ 6,980 | $ 8,539
Goodwill acquired and adjusted during period | 150 |
Impairment | (972) | (1,485)
Currency translation adjustments and other | (91) | (74)
Goodwill, Ending Balance | 6,067 | 6,980
Rig Systems [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 1,232 | 1,236
Impairment | (972) |
Currency translation adjustments and other | (2) | (4)
Goodwill, Ending Balance | 258 | 1,232
Rig Aftermarket [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 877 | 877
Goodwill, Ending Balance | 877 | 877
Wellbore Technologies [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 2,874 | 4,357
Goodwill acquired and adjusted during period | 24 | 8
Impairment |  | (1,485)
Currency translation adjustments and other | (24) | (6)
Goodwill, Ending Balance | 2,874 | 2,874
Completion & Production Solutions [Member] |  |
Goodwill [Line Items] |  |
Goodwill, Beginning Balance | 1,997 | 2,069
Goodwill acquired and adjusted during period | 126 | (8)
Currency translation adjustments and other | (65) | (64)
Goodwill, Ending Balance | $ 2,058 | $ 1,997

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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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975 + Details
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- Definition Amount of loss from the write-down of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13854-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13777-109266 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=66902209&loc=d3e3602-108585 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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