v3.19.2

Variable Interest Entities and Unconsolidated Investments in Power Plants (Unconsolidated VIEs) (Details) - USD ($) $ in Millions		Jun. 30, 2019	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Equity method investments		$ 71	$ 76
Equity method investment, ownership percentage		50.00%
Greenfield [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments	[1]	$ 56	55
Equity method investment, ownership percentage		50.00%
Whitby [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments		$ 10	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%
[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.

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

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