CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2021	Mar. 31, 2020
OPERATING REVENUE
Total operating revenue	$ 1,792	$ 1,918
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	439	473
Selling, general and administrative	107	143
Operating expenses - affiliates	194	195
Depreciation and amortization	317	328
Total operating expenses	1,057	1,139
OPERATING INCOME	735	779
OTHER (EXPENSE) INCOME
Interest expense	(48)	(75)
Interest expense - affiliates, net	(31)	(16)
Other expense, net	(6)	(8)
Total other expense, net	(85)	(99)
INCOME BEFORE INCOME TAXES	650	680
Income tax expense	168	177
NET INCOME	482	503
Non-affiliate services
OPERATING REVENUE
Total operating revenue	1,170	1,235
Affiliate Services [Member]
OPERATING REVENUE
Total operating revenue	$ 622	$ 683