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Summary of Significant Accounting Policies - Identified Intangible Assets Identified by Segment (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | $ 3,849 | $ 4,444
Additions to intangible assets | 24 | 59
Asset impairment |  | (204)
Amortization | (333) | (356)
Currency translation adjustments and other | (10) | (94)
Ending Balance | 3,530 | 3,849
Rig Systems [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 176 | 208
Asset impairment |  | (7)
Amortization | (15) | (22)
Currency translation adjustments and other | (1) | (3)
Ending Balance | 160 | 176
Rig Aftermarket [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 123 | 133
Amortization | (7) | (6)
Currency translation adjustments and other | (1) | (4)
Ending Balance | 115 | 123
Wellbore Technologies [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 2,254 | 2,666
Additions to intangible assets | 15 | 2
Asset impairment |  | (173)
Amortization | (205) | (214)
Currency translation adjustments and other |  | (27)
Ending Balance | 2,064 | 2,254
Completion & Production Solutions [Member] |  |
Intangible Asset Excluding Goodwill [Line Items] |  |
Beginning Balance | 1,296 | 1,437
Additions to intangible assets | 9 | 57
Asset impairment |  | (24)
Amortization | (106) | (114)
Currency translation adjustments and other | (8) | (60)
Ending Balance | $ 1,191 | $ 1,296

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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 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6388964&loc=d3e16225-109274 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=66902209&loc=d3e3602-108585 Reference 3: 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=66006027&loc=d3e16323-109275 + Details
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- Definition Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 360 -SubTopic 10 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=68055307&loc=d3e2420-110228 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=66902209&loc=d3e3602-108585 + 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=66006027&loc=d3e16323-109275 + Details
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