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Summary of Significant Accounting Policies - Additional Information (Detail) shares in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2016 USD ($) | Dec. 31, 2015 USD ($) | Mar. 31, 2015 USD ($) | Dec. 31, 2016 USD ($) Reporting_Unit shares | Dec. 31, 2015 USD ($) shares | Dec. 31, 2014 USD ($) shares
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Maturity period of investments description |  |  |  | Three months or less |  |
Minimum derivative financial instrument's term (months) |  |  |  | 2 months |  |
Maximum derivative financial instrument's term (months) |  |  |  | 24 months |  |
Additional inventory reserve charges |  |  |  | $ 582,000,000 |  |
Inventory reserves total |  | $ 500,000,000 |  | $ 1,017,000,000 | $ 500,000,000 |
Percentage of inventory reserve |  | 9.70% |  | 23.40% | 9.70% |
Depreciation expense related to property, plant and equipment |  |  |  | $ 370,000,000 | $ 391,000,000 | $ 413,000,000
Accumulated depreciation |  | $ 2,152,000,000 |  | 2,298,000,000 | 2,152,000,000 |
Accumulated depreciation for capital leases |  |  |  | 6,000,000 |  |
Impairment of long-lived assets |  |  |  | 54,000,000 | 0 | 0
Goodwill |  | 6,980,000,000 |  | 6,067,000,000 | 6,980,000,000 | 8,539,000,000
Indefinite-lived intangible assets |  | 3,849,000,000 |  | $ 3,530,000,000 | 3,849,000,000 |
Estimated useful lives of intangible assets, minimum |  |  |  | 2 years |  |
Estimated useful lives of intangible assets, maximum |  |  |  | 30 years |  |
Amortization expense |  |  |  | $ 320,000,000 |  |
Number of years as first period of amortization |  |  |  | 5 years |  |
Impairment of goodwill |  |  |  | $ 972,000,000 | 1,485,000,000 |
Net foreign currency transaction gains (losses) |  |  |  | (10,000,000) | (47,000,000) | $ 20,000,000
Net investment in Venezuela |  |  |  | 0 |  |
Devaluation charges |  | 7,000,000 | $ 9,000,000 |  |  |
Net allowances for doubtful accounts |  | 159,000,000 |  | $ 209,000,000 | $ 159,000,000 |
Anti-dilutive stock options outstanding | shares |  |  |  | 14 | 13 | 8
Indefinite-lived Trade Names [Member] |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Indefinite-lived intangible assets |  |  |  | $ 384,000,000 |  |
Rig Systems [Member] |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Goodwill |  | $ 1,232,000,000 |  | 258,000,000 | $ 1,232,000,000 | $ 1,236,000,000
Impairment of goodwill |  |  |  | $ 972,000,000 |  |
Number of reporting units has impairment loss | Reporting_Unit |  |  |  | 2 |  |
Rig Offshore [Member] |  |  |  |  |  |
Indefinite-lived Intangible Assets [Line Items] |  |  |  |  |  |
Impairment of goodwill | $ 972,000,000 |  |  |  |  |

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