v3.19.1

Revenue From Contracts with Customers Performance Obligations and Contract Balances (Details) - Environmental Credits [Member] - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Disaggregation of Revenue [Line Items] |  |  |
Deferred Revenue, Current | $ 19 |  | $ 14
Deferred Revenue, Revenue Recognized | $ 2 | $ 5 |

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- Definition The carrying amount of consideration received or receivable as of the balance sheet date on potential earnings that were not recognized as revenue in conformity with GAAP, and which are expected to be recognized as such within one year or the normal operating cycle, if longer, including sales, license fees, and royalties, but excluding interest income. + References Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 8 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82887183&loc=d3e6935-107765 + Details
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- Definition Amount of revenue recognized that was previously reported as deferred or unearned revenue. + References No definition available. + 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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- Details
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