Equity Method Investments and Variable Interest Entities (Consolidated Summarized Financial Information - Statements of Operations) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Equity Method Investments and Joint Ventures [Abstract]
Revenues	$ 2,592	$ 3,190	$ 5,781
Operating income	92	197	278
Net income	$ 48	$ 173	$ 145

The amount of net income (loss) reported by an equity method investment of the entity.

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