STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Operating activities
Net Income (Loss) Attributable to Parent	$ 295	$ 263	$ 213
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	298	232	210
Demand side management program amortization	0	0	2
Deferred income taxes	22	29	22
Allowance for equity funds used during construction	(33)	(27)	(19)
Provision for bad debts	6	6	5
Changes in operating assets and liabilities:
Accounts receivable	(14)	(9)	(20)
Increase (Decrease) in Accrued Unbilled Revenues	0	(1)	15
Inventories	(35)	(21)	(16)
Prepayments and other	(14)	3	1
Accounts payable	8	(9)	(7)
Net regulatory assets and liabilities	(115)	14	38
Other current liabilities	13	6	12
Pension and other employee benefit obligations	(16)	(18)	(16)
Other, net	(1)	5	6
Net cash provided by operating activities	414	473	446
Investing activities
Utility capital/construction expenditures	(1,142)	(844)	(1,021)
Investments in utility money pool arrangement	(4)	(133)	(285)
Receipts from utility money pool arrangement	4	133	350
Net cash used in investing activities	(1,142)	(844)	(956)
Financing activities
Proceeds from (repayments of) short-term borrowings, net	250	(42)	42
Proceeds from issuance of long-term debt	343	292	295
Borrowings under utility money pool arrangement	561	296	595
Repayments under utility money pool arrangement	(561)	(296)	(595)
Capital contributions from parent	438	426	337
Dividends paid to parent	(313)	(333)	(131)
Net cash provided by financing activities	718	343	543
Net change in cash and cash equivalents	(10)	(28)	33
Cash and cash equivalents at beginning of period	16	44	11
Cash and cash equivalents at end of period	6	16	44
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(98)	(84)	(71)
Cash paid for income taxes, net	10	12	(11)
Supplemental disclosure of non-cash investing transactions:
Accrued property, plant and equipment additions	99	95	72
Inventory transfers to plant, property and equipment	31	23	23
Operating lease right-of-use assets	0	548	0
Allowance for Funds Used During Construction, Investing Activities	$ 33	$ 27	$ 19