Investment in Unconsolidated Entities - Schedule of Investments (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
Equity Method Investments and Joint Ventures [Abstract]
Equity method investments	$ 464		$ 464		$ 467
Measurement alternative method investments	22		22		21
Total investments in unconsolidated entities	486	$ 490	486	$ 490	$ 488
Schedule of Equity Method Investments [Line Items]
Revenues	1,263	1,261	2,524	2,518
Operating expenses	1,185	1,213	2,373	2,376
Operating income	78	48	151	142
Other income (expense), net	0	0	(1)	1
Net income	78	39	161	109
Equity Method Investments
Schedule of Equity Method Investments [Line Items]
Revenues	1,586	1,660	3,249	3,356
Operating expenses	1,098	1,192	2,265	2,413
Operating income	488	468	984	943
Other income (expense), net	(2)	3	1	(3)
Net income	$ 486	$ 471	$ 985	$ 940