CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
OPERATING REVENUES:
Total operating revenues	$ 135	$ 137	$ 432	$ 420
OPERATING EXPENSES:
Cost of natural gas and other energy	0	0	0	2
Operating and maintenance	48	57	144	158
General and administrative	8	8	22	22
Depreciation and amortization	26	31	85	91
Goodwill impairment	12	0	12	0
Total operating expenses	94	96	263	273
OPERATING INCOME	41	41	169	147
OTHER INCOME (EXPENSE):
Interest expense, net	(3)	(5)	(13)	(23)
Interest Expense, Related Party	(6)	(5)	(15)	(8)
Other, net	(2)	0	(2)	(2)
INCOME BEFORE INCOME TAX EXPENSE (BENEFIT)	30	31	139	114
Income tax expense	(445)	8	(417)	35
NET INCOME	475	23	556	79
OTHER COMPREHENSIVE INCOME, NET OF TAX
Actuarial income relating to postretirement benefit plans	6	1	15	0
COMPREHENSIVE INCOME	481	24	571	79
Natural Gas, US Regulated [Member]
OPERATING REVENUES:
Transportation and storage of natural gas	130	128	415	401
Product and Service, Other [Member]
OPERATING REVENUES:
Transportation and storage of natural gas	$ 5	$ 9	$ 17	$ 19