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Summary of Significant Accounting Policies - Goodwill is Identified by Segment (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2015 | Dec. 31, 2015 | Dec. 31, 2014
Goodwill [Line Items] |  |  |
Goodwill, Beginning Balance |  | $ 8,539 | $ 9,049
Goodwill acquired and adjusted during period |  |  | 167
Goodwill disposed of during the period |  |  | (403)
Impairment |  | (1,485) |
Currency translation adjustments and other |  | (74) | (274)
Goodwill, Ending Balance | $ 6,980 | 6,980 | 8,539
Discontinued Operations [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill, Beginning Balance |  |  | 333
Goodwill disposed of during the period |  |  | (332)
Currency translation adjustments and other |  |  | (1)
Rig Systems [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill, Beginning Balance |  | 1,236 | 1,279
Currency translation adjustments and other |  | (4) | (43)
Goodwill, Ending Balance | 1,232 | 1,232 | 1,236
Rig Aftermarket [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill, Beginning Balance |  | 877 | 906
Currency translation adjustments and other |  |  | (29)
Goodwill, Ending Balance | 877 | 877 | 877
Wellbore Technologies [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill, Beginning Balance |  | 4,357 | 4,425
Goodwill acquired and adjusted during period |  | 8 | 17
Impairment | (1,485) | (1,485) |
Currency translation adjustments and other |  | (6) | (85)
Goodwill, Ending Balance | 2,874 | 2,874 | 4,357
Completion & Production Solutions [Member] |  |  |
Goodwill [Line Items] |  |  |
Goodwill, Beginning Balance |  | 2,069 | 2,106
Goodwill acquired and adjusted during period |  | (8) | 150
Goodwill disposed of during the period |  |  | (71)
Currency translation adjustments and other |  | (64) | (116)
Goodwill, Ending Balance | $ 1,997 | $ 1,997 | $ 2,069

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