v3.20.2

Variable Interest Entities and Unconsolidated Investments (Unconsolidated VIEs) (Details) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Return on investments from unconsolidated subsidiaries				$ 0	$ 11
Equity method investment, ownership percentage		50.00%		50.00%
Equity method investments		$ 67		$ 67		$ 70
Greenfield
Schedule of Equity Method Investments [Line Items]
Return on investments from unconsolidated subsidiaries				$ 0
Equity method investment, ownership percentage		50.00%		50.00%
Equity method investments	[1]	$ 63		$ 63		66
Calpine Receivables
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage		100.00%		100.00%
Equity method investments		$ 4		$ 4		$ 4
Whitby
Schedule of Equity Method Investments [Line Items]
Return on investments from unconsolidated subsidiaries			$ 0		$ 11
[1] Includes our share of AOCI related to interest rate hedging instruments associated with our unconsolidated subsidiary Greenfield LP’s debt.

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