v3.19.3.a.u2

Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |  |
Current |  | $ 299 | $ 167 |
Non-current |  | 46 | 34 |
Total |  | 345 | 201 |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Gain on Business Interruption Insurance Recovery |  | $ 11 | 14 | $ 27
Income Taxes Threshold Percentage |  | 50.00% |  |
Property, plant and equipment, salvage value (as a percent) |  | 10.00% |  |
Goodwill |  | $ 242 | 242 |
Impairment losses |  | 84 | 10 | 41
Asset retirement obligations |  | 68 | 63 |
Long-term Debt |  | 11,857 | 10,156 |
Property, Plant and Equipment, Net |  | $ 11,963 | 12,442 |
Freestone Energy Center [Member] |  |  |  |
Jointly Owned Plants [Abstract] |  |  |  |
Jointly Owned Utility Plant, Proportionate Ownership Share |  | 75.00% |  |
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service |  | $ 379 |  |
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation |  | (177) |  |
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress |  | $ 0 |  |
Hidalgo Energy Center [Member] |  |  |  |
Jointly Owned Plants [Abstract] |  |  |  |
Jointly Owned Utility Plant, Proportionate Ownership Share |  | 78.50% |  |
Jointly Owned Utility Plant, Gross Ownership Amount of Plant in Service |  | $ 250 |  |
Jointly Owned Utility Plant, Ownership Amount of Plant Accumulated Depreciation |  | (113) |  |
Jointly Owned Utility Plant, Ownership Amount of Construction Work in Progress |  | 0 |  |
Debt Service |  |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |  |
Current |  | 58 | 13 |
Non-current |  | 8 | 8 |
Total |  | 66 | 21 |
Construction Major Maintenance |  |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |  |
Current |  | 28 | 23 |
Non-current |  | 6 | 24 |
Total |  | 34 | 47 |
Security Project Insurance |  |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |  |
Current |  | 209 | 120 |
Non-current |  | 31 | 0 |
Total |  | 240 | 120 |
Other |  |  |  |
Restricted Cash and Cash Equivalents Items [Line Items] |  |  |  |
Current |  | 4 | 11 |
Non-current |  | 1 | 2 |
Total |  | $ 5 | 13 |
Greenfield [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Ownership percentage in equity method investment | [1] | 50.00% |  |
Whitby [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Ownership percentage in equity method investment | [2] | 0.00% |  |
Calpine Receivables [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Ownership percentage in equity method investment |  | 100.00% |  |
West [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Impairment losses |  | $ 0 | 0 | 28
Texas [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Impairment losses |  | 13 | 0 | 13
East [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Impairment losses |  | 71 | $ 10 | $ 0
Russell City Energy [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Long-term Debt |  | 272 |  |
Property, Plant and Equipment, Net |  | 647 |  |
Los Esteros Project [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
Long-term Debt |  | 135 |  |
Property, Plant and Equipment, Net |  | 427 |  |
Minimum [Member] |  |  |  |
Basis Of Presentation and Summary of Significant Accounting Policies (Textuals) [Abstract] |  |  |  |
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification |  | $ 191 |  |
[1] | Includes our share of accumulated other comprehensive income/loss related to interest rate hedging instruments associated with our unconsolidated subsidiary Greenfield LP’s debt.
[2] | On November 20, 2019, we sold our 50% interest in Whitby to a third party and recorded a gain on sale of assets, net of approximately $5 million.

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