CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) - USD ($) $ in Millions	3 Months Ended				6 Months Ended
	Jun. 30, 2020	Mar. 31, 2020	Jun. 30, 2019	Mar. 31, 2019	Jun. 30, 2020	Jun. 30, 2019
Total other expenses (income)	$ (48)		$ (55)		$ (103)	$ (106)
Total operating expenses	133		149		276	290
NET INCOME	121	$ 92	87	$ 84	213	171
OTHER COMPREHENSIVE INCOME
Derivative instruments, net of tax (Note 11)	(1)	$ (16)	1		(17)	1
TOTAL COMPREHENSIVE INCOME	$ 120		$ 88		$ 196	$ 172