v3.20.1

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Dec. 31, 2019
Fair Value Measurement [Domain] |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Cash and Cash Equivalents, at Carrying Value |  | $ 222 |  | $ 573
Restricted Cash and Cash Equivalents |  | 222 |  | 211
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 171 | $ (8) |
Included in operating revenues | [1] | 81 | 50 |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense | [2] | (4) | 2 |
Amount of Change in Collateral of Financial Instruments Classified as Derivative Asset (Liability) |  | 0 | 2 |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases |  | 0 | 2 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 0 | 58 |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount |  |  | 0 |
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount |  | 0 | 0 |
Transfers into level 3 | [3],[4] | 3 | (1) |
Transfers out of Level 3 | [3],[5] | (2) | 0 |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 249 | 105 |
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) |  | 77 | $ 52 |
Cash and Cash Equivalents, at Carrying Value |  | 531 |  | 1,131
Restricted Cash and Cash Equivalents |  | 306 |  | 345
Level 1 |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 35 |  | 112
Level 2 |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 8 |  | 2
Level 3 |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | $ 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 $3 million in gains and $(1) million in losses transferred out of level 2 into level 3 for the three months ended March 31, 2020 and 2019, respectively, due to changes in market liquidity in various power markets.
[5] | We had $2 million in gains and nil transferred out of level 3 into level 2 for the three months ended March 31, 2020 and 2019, respectively, due to changes in market liquidity in various power markets.

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