Interest and Other Income (Loss), Net (Components of Interest and Other Income) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Interest and Other Income [Abstract]
Interest income	$ 0	$ 5	$ 2	$ 12
Investment in affiliate mark-to-market adjustment (Note 4)	(44)	3	101	(171)
Contingent consideration valuation adjustment	(1)	(13)	(64)	(13)
Other	5	0	5	11
Interest and other income (loss), net	$ 48	$ (11)	$ (158)	$ 181