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Goodwill Impairment - Goodwill Identified by Segment (Detail) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2016
Goodwill [Line Items] |
Gross value before accumulated impairment | $ 8,465
Accumulated impairment | (1,485)
Goodwill, Beginning Balance | 6,980
Goodwill acquired and adjusted during period | (6)
Impairment | (972)
Currency translation adjustments and other | 13
Goodwill, Ending Balance | 6,015
Rig Systems [Member] |
Goodwill [Line Items] |
Gross value before accumulated impairment | 1,232
Goodwill, Beginning Balance | 1,232
Goodwill acquired and adjusted during period | 1
Impairment | (972)
Goodwill, Ending Balance | 261
Rig Aftermarket [Member] |
Goodwill [Line Items] |
Gross value before accumulated impairment | 877
Goodwill, Beginning Balance | 877
Goodwill, Ending Balance | 877
Wellbore Technologies [Member] |
Goodwill [Line Items] |
Gross value before accumulated impairment | 4,359
Accumulated impairment | (1,485)
Goodwill, Beginning Balance | 2,874
Goodwill acquired and adjusted during period | (7)
Currency translation adjustments and other | 4
Goodwill, Ending Balance | 2,871
Completion & Production Solutions [Member] |
Goodwill [Line Items] |
Gross value before accumulated impairment | 1,997
Goodwill, Beginning Balance | 1,997
Currency translation adjustments and other | 9
Goodwill, Ending Balance | $ 2,006

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