v3.19.1

Acquisitions, Divestitures and Discontinued Operations (Textuals) (Details) $ in Millions | 3 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($) | Dec. 31, 2016 USD ($) | Jan. 17, 2017 USD ($) | Dec. 01, 2016 USD ($) | Oct. 26, 2016 MW | Feb. 05, 2016 USD ($) MW
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Business Acquisition, Pro Forma Revenue |  |  |  |  |  | $ 8,324 |  |  |  |
Business Acquisition, Pro Forma Net Income (Loss) |  |  |  |  |  | 105 |  |  |  |
(Gain) on sale of power plants, net |  |  |  | $ 0 | $ 27 | 157 |  |  |  |
Calpine Solutions [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net |  |  |  |  |  |  |  | $ 1,150 |  |
Working Capital Adjustment to Sale price |  |  |  |  |  | 350 |  |  |  |
Recovered collateral subsequent to closing |  |  |  |  |  | 250 |  |  |  |
Expected recovery through collateral synergies |  |  |  |  |  |  |  | $ 200 |  |
Number of States in which Entity Operates |  |  |  |  |  |  |  | 20 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets |  |  |  |  |  |  |  | $ 141 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets |  |  |  |  |  |  |  | 518 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Derivative assets | [1] |  |  |  |  |  |  | 365 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment |  |  |  |  |  |  |  | 7 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles | [2] |  |  |  |  |  |  | 360 |  |
Business Acquisition, Goodwill, Expected Tax Deductible Amount |  |  |  |  |  |  |  | 162 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Long-term derivative asset | [1] |  |  |  |  |  |  | 359 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets |  |  |  |  |  |  |  | 1,912 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities |  |  |  |  |  |  |  | 276 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Derivative liabilities, current | [1] |  |  |  |  |  |  | 270 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Long-term derivative liabilities | [1] |  |  |  |  |  |  | 216 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities |  |  |  |  |  |  |  | $ 762 |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  | $ 800 |  |  | $ 800 |  |  |  |
North American Power [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Ownership Percentage of Acquiree |  |  |  |  |  |  | 100.00% |  |  |
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  | $ 105 |  |  |
Granite Ridge Energy Center [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Summer peaking capacity | MW |  |  |  |  |  |  |  |  |  | 695
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net |  |  |  |  |  |  |  |  |  | $ 500
Power generation capacity | MW |  |  |  |  |  |  |  |  |  | 745
Osprey Energy Center [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from Sale of Productive Assets |  | $ 166 |  |  |  |  |  |  |  |
(Gain) on sale of power plants, net |  | $ 27 |  |  |  |  |  |  |  |
Mankato [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Proceeds from Sale of Productive Assets |  |  | 396 |  |  |  |  |  |  |
Gain (Loss) on Sale of Assets and Asset Impairment Charges |  |  | $ 157 |  |  |  |  |  |  |
Power generation capacity | MW |  |  |  |  |  |  |  |  | 375 |
Expansion generation capacity | MW |  |  |  |  |  |  |  |  | 345 |
Acquired contracts [Member] | Calpine Solutions [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 5 years |  |  |  |  |  |  |
Customer Relationships [Member] | Calpine Solutions [Member] |  |  |  |  |  |  |  |  |  |
Business Acquisition [Line Items] |  |  |  |  |  |  |  |  |  |
Finite-Lived Intangible Asset, Useful Life |  |  | 14 years |  |  |  |  |  |  |
[1] | Consists of acquired customer and wholesale contracts which will be substantially amortized over 5 years.
[2] | Consists primarily of customer relationships that are being amortized over 14 years. See Note 3 for a further description of our intangible assets.

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- Definition The amount of property, plant, and equipment recognized as of the acquisition date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 55 -Paragraph 37 -URI http://asc.fasb.org/extlink&oid=108330185&loc=d3e2207-128464 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=84161108&loc=d3e4845-128472 + Details
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