v3.20.2

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Dec. 31, 2019 | Mar. 31, 2019
Fair Value Measurement [Domain] |  |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |  |
Cash and Cash Equivalents, at Carrying Value |  | $ 190 |  | $ 190 |  | $ 573 |
Restricted Cash and Cash Equivalents |  | 227 |  | 227 |  | 211 |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 249 | $ 105 | 171 | $ (8) |  |
Included in operating revenues | [1] | 37 | 152 | 106 | 197 |  |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense | [2] | 3 | 1 | (1) | 2 |  |
Amount of Change in Collateral of Financial Instruments Classified as Derivative Asset (Liability) |  | 0 | (1) | 0 | 1 |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases |  | 1 | 1 | 1 | 3 |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Issues |  | 0 | (1) | 0 | (1) |  |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | (49) | (35) | (36) | 28 |  |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount |  |  |  |  |  |  | $ 0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount |  | 0 |  | 0 |  |  | $ 0
Transfers into level 3 | [3],[4] | 10 | 6 | 11 | 7 |  |
Transfers out of Level 3 | [3],[5] | (5) | (1) | (6) | (2) |  |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 246 | 227 | 246 | 227 |  |
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) |  | 40 | $ 153 | 105 | $ 199 |  |
Cash and Cash Equivalents, at Carrying Value |  | 677 |  | 677 |  | 1,131 |
Restricted Cash and Cash Equivalents |  | 241 |  | 241 |  | 345 |
Level 1 |  |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 10 |  | 10 |  | 112 |
Level 2 |  |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | (3) |  | (3) |  | 2 |
Level 3 |  |  |  |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | $ 0 |  | $ 0 |  | $ 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] | (2)Amount represents the arithmetic average of the significant unobservable input based on the range disclosed.
[4] | We had $10 million and $6 million in gains transferred out of level 2 into level 3 for the three months ended June 30, 2020 and 2019, respectively, and $11 million and $7 million in gains transferred out of level 2 into level 3 for the six months ended June 30, 2020 and 2019, respectively, due to changes in market liquidity in various power markets.
[5] | We had $5 million and $1 million in gains transferred out of level 3 into level 2 for the three months ended June 30, 2020 and 2019, respectively, and $6 million and $2 million in gains transferred out of level 3 into level 2 for the six months ended June 30, 2020 and 2019, respectively, due to changes in market liquidity in various power markets.

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