CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
OPERATING REVENUES:
Total operating revenues	$ 132	$ 135	$ 402	$ 432
OPERATING EXPENSES:
Operating and maintenance	40	48	129	144
General and administrative	10	8	29	22
Depreciation and amortization	27	26	79	85
Asset Impairment Charges	0	12	0	12
Total operating expenses	77	94	237	263
OPERATING INCOME	55	41	165	169
OTHER INCOME (EXPENSE):
Interest expense, net	(3)	(3)	(10)	(13)
Interest expense — related company	(8)	(6)	(25)	(15)
Other, net	(1)	(2)	(5)	(2)
INCOME BEFORE INCOME TAX BENEFIT	43	30	125	139
Income tax expense	(1)	(445)	(2)	(417)
NET INCOME	44	475	127	556
OTHER COMPREHENSIVE INCOME, NET OF TAX
Actuarial gain relating to postretirement benefit plans	4	6	13	15
COMPREHENSIVE INCOME	48	481	140	571
Natural Gas, US Regulated [Member]
OPERATING REVENUES:
Transportation and storage of natural gas	127	130	388	415
Product and Service, Other [Member]
OPERATING REVENUES:
Transportation and storage of natural gas	$ 5	$ 5	$ 14	$ 17