CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
OPERATING REVENUES
Operating revenues	$ 5,831	$ 6,247	$ 6,557
Operating revenues - affiliates	2,719	2,663	2,407
Total operating revenues	8,550	8,910	8,964
OPERATING EXPENSES
Cost of services and products (exclusive of depreciation and amortization)	2,881	2,934	2,872
Selling, general and administrative	925	1,020	1,015
Operating expenses - affiliates	848	941	960
Depreciation and amortization	1,583	1,691	1,857
Total operating expenses	6,237	6,586	6,704
OPERATING INCOME	2,313	2,324	2,260
OTHER (EXPENSE) INCOME
Interest expense	(465)	(478)	(473)
Interest expense - affiliates, net	(63)	(59)	(53)
Other income (expense), net	6	(24)	(1)
Total other expense, net	(522)	(561)	(527)
INCOME BEFORE INCOME TAX EXPENSE	1,791	1,763	1,733
Income tax expense	134	678	659
NET INCOME	$ 1,657	$ 1,085	$ 1,074