Fair Value of Financial Assets and Liabilities, Changes in Level 3 Commodity Derivatives (Details) - Commodity Contract - USD ($) |
3 Months Ended | 9 Months Ended | ||||
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Sep. 30, 2018 |
Sep. 30, 2017 |
Sep. 30, 2018 |
Sep. 30, 2017 |
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| Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Input Reconciliation [Roll Forward] | ||||||
| Balance at beginning of period | $ 64,000,000 | $ 69,000,000 | $ 35,000,000 | $ 17,000,000 | ||
| Purchases | 3,000,000 | 0 | 49,000,000 | 80,000,000 | ||
| Settlements | (19,000,000) | (33,000,000) | (51,000,000) | (75,000,000) | ||
| Gains (losses) recognized in earnings | [1] | 0 | 1,000,000 | 0 | 6,000,000 | |
| Net gains recognized as regulatory assets and liabilities | 0 | 29,000,000 | 15,000,000 | 38,000,000 | ||
| Balance at end of period | 48,000,000 | 66,000,000 | 48,000,000 | 66,000,000 | ||
| Transfers into Level 3 | 0 | 0 | 0 | 0 | ||
| Transfers out of Level 3 | $ 0 | $ 0 | $ 0 | $ 0 | ||
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of gain (loss) recognized in the income statement of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of purchases of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of settlements of financial instrument classified as a derivative asset (liability) after deduction of derivative liability, measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of transfers of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset) into level 3 of the fair value hierarchy. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of transfers of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset) out of level 3 of the fair value hierarchy. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Fair value of financial instrument classified as derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition This element represents total gains (losses) for the period (realized and unrealized), arising from net assets and liabilities measured at fair value on a recurring basis using unobservable inputs (Level 3), which are recognized in regulatory assets and liabilities. No definition available.
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- Details
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