v3.19.1

Variable Interest Entities and Unconsolidated Investments in Power Plants (Unconsolidated VIEs) (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 67	$ 76
Equity method investment, ownership percentage	50.00%
Greenfield [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 54	55
Equity method investment, ownership percentage	50.00%
Whitby [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 8	15
Equity method investment, ownership percentage	50.00%
Calpine Receivables [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments	$ 5	$ 6
Equity method investment, ownership percentage	100.00%

X

- 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
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- Definition

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

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