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Contingencies and Environmental Liabilities - Commercial and Other Litigation- Narrative (Details) $ in Millions |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Apr. 29, 2016 legalmatter | Feb. 28, 2017 USD ($) | Jan. 31, 2014 legalmatter | Dec. 31, 2017 USD ($) legalmatter | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Loss Contingencies [Line Items] |  |  |  |  |  |
Litigation settlement | $ |  | $ (80) |  | $ 0 | $ (625) | $ 0
Commercial Litigation |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |
Additional claims filed | 1 |  | 4 |  |  |
Loss contingency, pending claims number |  |  |  | 700 |  |
Number of plaintiffs |  |  |  | 2 |  |
Loss contingency, claims on appeal, number |  |  |  | 2 |  |

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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://www.xbrl.org/2003/role/presentationRef -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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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition The total number of new claims filed pertaining to a loss contingency during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
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- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
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- Details
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