v3.19.1

Variable Interest Entities and Unconsolidated Investments (Unconsolidated VIEs) (Details) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Equity Method Investments Included on Balance Sheet [Abstract]
Equity Method Investments	$ 76	$ 106
Greenfield [Member]
Equity Method Investments Included on Balance Sheet [Abstract]
Equity Method Investments	$ 55	92
Equity Method Investment, Ownership Percentage	50.00%
Whitby [Member]
Equity Method Investments Included on Balance Sheet [Abstract]
Equity Method Investments	$ 15	6
Equity Method Investment, Ownership Percentage	50.00%
Calpine Receivables [Member]
Equity Method Investments Included on Balance Sheet [Abstract]
Equity Method Investments	$ 6	$ 8
Equity Method Investment, Ownership Percentage	100.00%

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- Definition

Equity Method Investments Included on Balance Sheet [Abstract]

+ References

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
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