CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating activities
Net income	$ 108	$ 107	$ 79
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	148	158	139
Deferred income taxes	9	(36)	5
Allowance for equity funds used during construction	(5)	(5)	(3)
Provision for bad debts	4	7	7
Changes in operating assets and liabilities:
Accounts receivable	(5)	(12)	(10)
Accrued unbilled revenues	(16)	0	3
Inventories	(12)	(5)	(8)
Other current assets	(4)	(3)	13
Accounts payable	8	(3)	(10)
Net regulatory assets and liabilities	(41)	0	15
Other current liabilities	2	4	11
Pension and other employee benefit obligations	(9)	(7)	(7)
Other, net	(1)	(3)	0
Net cash provided by operating activities	186	202	234
Investing activities
Capital/construction expenditures	(264)	(238)	(212)
Investments In Utility Money Pool Arrangement	(71)	0	0
Repayments From Utility Money Pool Arrangement	71	0	0
Net cash used in investing activities	(264)	(238)	(212)
Financing activities
Proceeds from (repayments of) short-term borrowings, net	64	(46)	13
Proceeds from issuance of long-term debt	99	97	0
Repayments of long-term debt	(19)	0	0
Borrowings Under Utility Money Pool Arrangement	358	0	0
Repayments Under Utility Money Pool Arrangement	(358)	0	0
Capital contributions from parent	46	56	48
Dividends paid to parent	(103)	(70)	(84)
Net cash provided by (used in) financing activities	87	37	(23)
Net change in cash, cash equivalents and restricted cash	9	1	(1)
Cash, cash equivalents and restricted cash at beginning of period	2	1	2
Cash, cash equivalents and restricted cash at end of period	11	2	1
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(38)	(36)	(36)
Cash paid for income taxes, net	(22)	(26)	0
Other Noncash Investing and Financing Items [Abstract]
Supplemental disclosure of non-cash investing and financing transactions:	43	21	29
Inventory transfers to plant, property and equipment	1	5	9
Allowance for Funds Used During Construction, Investing Activities	$ 5	$ 5	$ 3