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Contingencies (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 USD ($) name | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($)
Loss Contingencies [Line Items] |  |  |
Proceeds from Insurance Settlement, Investing Activities | $ 0 | $ 0 | $ 120
Site Contingency, Names of Other Potentially Responsible Parties | name | 100 |  |
Litigation Settlement, Expense | $ 115 |  |
Loss Contingency, Range of Possible Loss, Maximum | 1,700 |  |
Loss Contingency, Range of Possible Loss, Portion Not Accrued | 500 |  |
Payments for Environmental Liabilities | $ 6 |  |
Loss Contingency, Damages Sought | 260 million |  |
EPA Investigation of Portland Harbor [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Loss Contingency, Damages Sought, Value | $ 1,200 |  |
Putative Shareholder Derivative Lawsuit [Member] |  |  |
Loss Contingencies [Line Items] |  |  |
Loss Contingency, Damages Sought, Value | $ 10 |  |

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- Definition Cash outflows made during the period for environmental remediation activities. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 17 -Subparagraph (f) -URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3367-108585 + Details
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