CONSOLIDATED STATEMENTS OF CASH FLOWS $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Operating activities
Net income	$ 660.0	$ 588.0	$ 578.0
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation and amortization	754.0	656.0	607.0
Deferred income taxes	21.0	2.0	97.0
Amortization of investment tax credits	11.0	0.0	0.0
Allowance for equity funds used during construction	(28.0)	(35.0)	(22.0)
Provision for bad debts	26.0	24.0	17.0
Net realized and unrealized hedging and derivative transactions	(44.0)	(14.0)	62.0
Changes in operating assets and liabilities:
Accounts receivable	(58.0)	(51.0)	(22.0)
Accrued unbilled revenues	(52.0)	(5.0)	20.0
Inventories	(71.0)	(27.0)	(27.0)
Prepayments and other	(23.0)	(8.0)	(29.0)
Accounts payable	66.0	(14.0)	(44.0)
Net regulatory assets and liabilities	(526.0)	58.0	35.0
Other current liabilities	30.0	45.0	0.0
Pension and other employee benefit obligations	(53.0)	(41.0)	(47.0)
Other, net	14.0	(4.0)	3.0
Net cash provided by operating activities	727.0	1,174.0	1,228.0
Investing activities
Utility capital/construction expenditures	(1,604.0)	(1,671.0)	(1,691.0)
Investments in utility money pool arrangement	(273.0)	(122.0)	(641.0)
Repayments from utility money pool arrangement	273.0	122.0	641.0
Net cash used in investing activities	(1,604.0)	(1,671.0)	(1,691.0)
Financing activities
Proceeds from (repayments of) short-term borrowings, net	11.0	136.0	(307.0)
Borrowings under utility money pool arrangement	743.0	1,189.0	100.0
Repayments under utility money pool arrangement	(800.0)	(1,171.0)	(61.0)
Proceeds from issuance of long-term debt	737.0	735.0	928.0
Repayments of long-term debt	0.0	(400.0)	(400.0)
Capital contributions from parent	650.0	856.0	638.0
Dividends paid to parent	(467.0)	(831.0)	(457.0)
Net cash provided by financing activities	874.0	514.0	441.0
Net change in cash and cash equivalents	(3.0)	17.0	(22.0)
Cash, cash equivalents and restricted cash at beginning of period	28.0	11.0	33.0
Cash, cash equivalents and restricted cash at end of period	25.0	28.0	11.0
Supplemental disclosure of cash flow information:
Cash paid for interest (net of amounts capitalized)	(230.0)	(211.0)	(209.0)
Cash paid for income taxes, net	(14.0)	(23.0)	(5.0)
Supplemental disclosure of non-cash investing and financing transactions:
Accrued property, plant and equipment additions	157.0	197.0	234.0
Inventory transfers to property, plant and equipment	10.0	35.0	32.0
Operating lease right-of-use assets	0.0	14.0	654.0
Allowance for equity funds used during construction	28.0	35.0	22.0
Net income	660.0	588.0	578.0
Depreciation, Amortization and Accretion, Net	754.0	656.0	607.0
Deferred Income Tax Expense (Benefit)	21.0	2.0	97.0
Amortization of investment tax credits	11.0	0.0	0.0
Allowance for funds used during construction — equity	28.0	35.0	22.0
Provision for bad debts	26.0	24.0	17.0
Gain (loss) on hedging and derivative transactions	44.0	14.0	(62.0)
Increase (Decrease) in Accounts and Other Receivables	58.0	51.0	22.0
Increase (Decrease) in Accrued Unbilled Revenues	52.0	5.0	(20.0)
Increase (Decrease) in Inventories	71.0	27.0	27.0
Increase (Decrease) in Prepaid Expense and Other Assets	23.0	8.0	29.0
Increase (Decrease) in Accounts Payable	66.0	(14.0)	(44.0)
Increase (Decrease) in Regulatory Assets and Liabilities	526.0	(58.0)	(35.0)
Increase (Decrease) in Other Current Liabilities	30.0	45.0	0.0
Increase (Decrease) in Employee Related Liabilities	(53.0)	(41.0)	(47.0)
Other, net	14.0	(4.0)	3.0
Net Cash Provided by (Used in) Operating Activities	727.0	1,174.0	1,228.0
Payments to Acquire Productive Assets	1,604.0	1,671.0	1,691.0
Investments In Utility Money Pool Arrangement	273.0	122.0	641.0
Repayments From Utility Money Pool Arrangement	273.0	122.0	641.0
Net Cash Provided by (Used in) Investing Activities	(1,604.0)	(1,671.0)	(1,691.0)
Proceeds from (repayments of) short-term borrowings, net	11.0	136.0	(307.0)
Borrowings Under Utility Money Pool Arrangement	743.0	1,189.0	100.0
Repayments Under Utility Money Pool Arrangement	800.0	1,171.0	61.0
Proceeds from issuance of long-term debt	737.0	735.0	928.0
Repayments of Long-term Debt	0.0	400.0	400.0
Capital contributions from parent	650.0	856.0	638.0
Payments of Ordinary Dividends, Common Stock	467.0	831.0	457.0
Net Cash Provided by (Used in) Financing Activities	874.0	514.0	441.0
Net change in cash and cash equivalents	(3.0)	17.0	(22.0)
Cash, cash equivalents and restricted cash at end of period	25.0	28.0	11.0
Interest Paid, Excluding Capitalized Interest, Operating Activities	230.0	211.0	209.0
Income Taxes Paid, Net	14.0	23.0	5.0
Accrued property, plant and equipment additions	157.0	197.0	234.0
Inventory transfers to property, plant and equipment	10.0	35.0	32.0
Operating lease right-of-use assets	0.0	14.0	654.0
Allowance for equity funds used during construction	$ 28.0	$ 35.0	$ 22.0