v3.19.1

Assets and Liabilities with Recurring Fair Value Measurements (Textuals) (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2018
Fair Value Measurement [Domain] |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Cash and Cash Equivalents, at Carrying Value |  | $ 19 |  | $ 23
Restricted Cash and Cash Equivalents |  | 156 |  | 145
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | (8) | $ 197 |
Included in operating revenues | [1] | 50 | (57) |
Fair Value, Assets Measured with Unobservable Inputs on Recurring Basis, Gain (Loss) Included In Fuel And Purchased Energy Expense | [2] | 2 | (2) |
Amount of Change in Collateral of Financial Instruments Classified as Derivative Asset (Liability) |  | 2 | (2) |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Purchases |  | 2 | 4 |
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset, Settlements |  | 58 | (14) |
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount |  | 0 | 0 |
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount |  | 0 | 0 |
Transfers into level 3 | [3],[4] | (1) | 6 |
Transfers out of Level 3 | [4],[5] | 0 | (3) |
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis with Unobservable Inputs |  | 105 | 129 |
Fair Value, Assets Measured on Recurring Basis, Change in Unrealized Gain (Loss) |  | 52 | $ (59) |
Cash and Cash Equivalents, at Carrying Value |  | 184 |  | 205
Restricted Cash and Cash Equivalents |  | 334 |  | 201
Fair Value, Inputs, Level 1 [Member] |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 76 |  | (1)
Fair Value, Inputs, Level 2 [Member] |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | 47 |  | 48
Fair Value, Inputs, Level 3 [Member] |  |  |  |
Fair Value Disclosures [Abstract] |  |  |  |
Derivative, Collateral, Right to Reclaim Cash, Net |  | $ 2 |  | $ 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 $(1) million in losses and $6 million in gains transferred out of level 2 into level 3 for the three months ended March 31, 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 months ended March 31, 2019 and 2018.
[5] | We had nil and $3 million in gains transferred out of level 3 into level 2 for the three months ended March 31, 2019 and 2018, respectively, due to changes in market liquidity in various power markets.

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