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Contingencies and Environmental Liabilities - Patent Litigation - Narrative (Details) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Jan. 31, 2018 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2018 USD ($) legalmatter | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($)
Gain Contingencies [Line Items] |  |  |  |  |
Litigation settlement, gain (loss) |  |  | $ 0 | $ 0 | $ (625)
Number of patents allegedly infringed upon | legalmatter |  |  | 2 |  |
Patent litigation |  |  |  |  |
Gain Contingencies [Line Items] |  |  |  |  |
Litigation settlement, gain (loss) | $ 115 |  |  |  |
Settlement awarded to company |  | $ 2,540 |  |  |

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- Definition Number of entity's patents that another entity has allegedly infringed. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in settlement of litigation and insurance claims. Excludes claims within an insurance entity's normal claims settlement process. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 + Details
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