Segment and Related Information, Reconciliation of EBITDA to income (loss) from continuing operations before income taxes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
EBITDA: [Abstract]
Total segment EBITDA	$ 655	$ 1,418
Other EBITDA	(9)	10
Less: [Abstract]
Depreciation and amortization expense	(342)	(322)
Interest expense	(89)	(92)
Add: [Abstract]
Interest income	3	6
Income from continuing operations before income taxes	$ 218	$ 1,020