v3.19.2

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2019 | Jun. 30, 2018 | Jun. 30, 2019 | Jun. 30, 2018 | Dec. 31, 2018
Fair Value Measurement [Domain] |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |
Cash and Cash Equivalents, at Carrying Value |  | $ 16 |  | $ 16 |  | $ 23
Restricted Cash and Cash Equivalents |  | 149 |  | 149 |  | 145
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 105 | $ 129 | (8) | $ 197 |
Included in operating revenues | [1] | 152 | 31 | 197 | (28) |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense | [2] | 1 | 18 | 2 | 15 |
Amount of Change in Collateral of Financial Instruments Classified as Derivative Asset (Liability) |  | (1) | 1 | 1 | (1) |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases |  | 1 | 5 | 3 | 9 |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Issues |  | (1) | 0 | (1) | 0 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | (35) | (42) | 28 | (53) |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount |  | 0 | 0 | 0 | 0 |
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount |  | 0 | 0 | 0 | 0 |
Transfers into level 3 | [3],[4] | 6 | (1) | 7 | (1) |
Transfers out of Level 3 | [4],[5] | (1) | (10) | (2) | (7) |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 227 | 131 | 227 | 131 |
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) |  | 153 | $ 49 | 199 | $ (13) |
Cash and Cash Equivalents, at Carrying Value |  | 297 |  | 297 |  | 205
Restricted Cash and Cash Equivalents |  | 262 |  | 262 |  | 201
Fair Value, Inputs, Level 1 [Member] |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 90 |  | 90 |  | (1)
Fair Value, Inputs, Level 2 [Member] |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 55 |  | 55 |  | 48
Fair Value, Inputs, Level 3 [Member] |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | $ 1 |  | $ 1 |  | $ 0
[1] | For power contracts and other power-related products, included on our Consolidated Condensed Statements of Operations.
[2] | For natural gas and power contracts, swaps and options, included on our Consolidated Condensed Statements of Operations.
[3] | We had $6 million in gains and $(1) million in losses transferred out of level 2 into level 3 for the three months ended June 30, 2019 and 2018, respectively, and $7 million in gains and $(1) million in losses transferred out of level 2 into level 3 for the six months ended June 30, 2019 and 2018, respectively, due to changes in market liquidity in various power markets.
[4] | We transfer amounts among levels of the fair value hierarchy as of the end of each period. There were no transfers into or out of level 1 for each of the three and six months ended June 30, 2019 and 2018.
[5] | We had $1 million and $10 million in gains transferred out of level 3 into level 2 for the three months ended June 30, 2019 and 2018, respectively, and $2 million and $7 million in gains transferred out of level 3 into level 2 for the six months ended June 30, 2019 and 2018, respectively, due to changes in market liquidity in various power markets.

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