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Derivative Accounting - Narrative (Details) $ in Millions | 9 Months Ended
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Sep. 30, 2018 USD ($)
Commodity Contracts |
Derivative Accounting |
Additional collateral to counterparties for energy related non-derivative instrument contracts | $ 94
Commodity Contracts | Designated as Hedging Instruments |
Derivative Accounting |
Estimated loss before income taxes to be reclassified from accumulated other comprehensive income | $ 2
APS |
Derivative Accounting |
Percentage of unrealized gains and losses on certain derivatives deferred for future rate treatment | 100.00%

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- Definition The aggregate fair value of additional assets that would be required to be posted as collateral for non-derivative instruments with credit-risk related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period. + References No definition available. + Details
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Balance Type: | debit
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- Definition Percentage of unrealized gains and losses on certain derivatives deferred for future rate treatment pursuant to the PSA mechanism that would otherwise be recognized in income. + References No definition available. + Details
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Balance Type: | na
Period Type: | instant

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- Definition The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=112277219&loc=d3e80748-113994 + 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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- Details
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- Details
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