CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE INCOME - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
OPERATING REVENUES:
Total operating revenues	$ 578	$ 574	$ 480
Cost of Goods and Services Sold	0	4	3
OPERATING EXPENSES:
Operating, maintenance and general	193	215	199
General and Administrative Expense	30	30	28
Depreciation and amortization	112	122	127
Asset Impairment Charges	12	0	389
Total operating expenses	347	371	746
Operating Income (Loss)	231	203	(266)
OTHER INCOME (EXPENSE):
Interest expense, net	(17)	(28)	(46)
Income from unconsolidated affiliates	(25)	(13)	0
Interest income — affiliates	0	0	10
Other, net	(2)	(5)	(6)
Total other expenses, net	(44)	(46)	(42)
Income (Loss) from Continuing Operations Before Income Tax Expense	187	157	(308)
Income tax expense (benefit)	(402)	49	(263)
Net Income (Loss)	589	108	(45)
Other Comprehensive Income (Loss), Defined Benefit Plan, Gain (Loss) Arising During Period, after Tax	23	(42)	(10)
Other Comprehensive Income (Loss), Securities, Available-for-sale, Adjustment, after Tax	0	0	2
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	612	66	(53)
Other Comprehensive (Income) Loss, Defined Benefit Plan, after Reclassification Adjustment, Tax	4	11	3
Natural Gas, Midstream [Member]
Income Statement
Revenue from Contract with Customer, Including Assessed Tax	556	544	460
Product and Service, Other [Member]
Income Statement
Revenue from Contract with Customer, Including Assessed Tax	$ 22	$ 30	$ 20