CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
OPERATING REVENUE
Total operating revenue	$ 7,933	$ 7,773	$ 7,839
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	3,486	3,387	3,556
Selling, general and administrative	1,226	1,258	1,354
Operating expenses - affiliates	368	334	257
Depreciation and amortization	1,689	1,613	1,704
Goodwill impairment	0	3,708	0
Total operating expenses	6,769	10,300	6,871
OPERATING INCOME (LOSS)	1,164	(2,527)	968
OTHER (EXPENSE) INCOME
Interest income - affiliate	51	61	63
Interest expense	(393)	(502)	(509)
Other income, net	50	22	15
Total other expense, net	(292)	(419)	(431)
INCOME (LOSS) BEFORE INCOME TAXES	872	(2,946)	537
Income tax expense	(221)	(255)	(196)
NET INCOME (LOSS)	651	(3,201)	341
Non-Affiliate Services
OPERATING REVENUE
Total operating revenue	7,725	7,593	7,732
Affiliate Services
OPERATING REVENUE
Total operating revenue	$ 208	$ 180	$ 107