Investments In and Advances To Affiliates (Details) - USD ($) $ in Millions	3 Months Ended		12 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Investments in and Advances to Affiliates [Line Items]
Revenue	$ 2,338	$ 2,650
Operating margin	507	586
Gain (Loss) on Disposition of Business	0	(4)
Income (Loss) from Equity Method Investments	(2)	(6)
Minority Owned Affiliates [Member]
Investments in and Advances to Affiliates [Line Items]
Revenue	370	214
Operating margin	55	11
Net Income (Loss), Including Portion Attributable to Nonredeemable Noncontrolling Interest	(11)	$ (21)
OPGC [Member]
Investments in and Advances to Affiliates [Line Items]
Equity Method Investments, Fair Value Disclosure	152		$ 212
Equity Method Investment OTTI	$ 43		$ 92