CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Operating activities
Net income	$ 134.3	$ 122.0
Reconciliation to cash provided by operating activities
Depreciation and amortization	139.6	127.8
Deferred income taxes and ITCs, net	8.1	(0.1)
Change in –
Accounts receivable and unbilled revenues, net	34.5	7.8
Materials, supplies, and inventories	22.4	59.0
Prepaid taxes	28.7	37.7
Collateral on deposit	3.6	(34.1)
Other current assets	(1.0)	(0.7)
Accounts payable	(64.5)	(141.8)
Accrued taxes	34.8	24.9
Amounts refundable to customers	16.7	31.1
Accrued interest	35.1	22.6
Other current liabilities	(20.6)	(36.1)
Other, net	(2.3)	(4.6)
Net cash provided by operating activities	369.4	215.5
Investing activities
Capital expenditures	(203.0)	(208.7)
Acquisition of Whitewater	0.0	(38.0)
Reimbursement for ATC's construction costs	6.2	0.0
Other, net	(0.5)	(2.6)
Net cash used in investing activities	(197.3)	(249.3)
Financing activities
Change in short-term debt	(83.9)	(333.2)
Payments for finance lease obligations	(20.7)	(18.3)
Equity contribution from parent	0.0	415.0
Payment of dividends to parent	(60.0)	(60.0)
Other, net	(0.3)	(0.3)
Net cash provided by (used in) financing activities	(164.9)	3.2
Net change in cash, cash equivalents, and restricted cash	7.2	(30.6)
Cash, cash equivalents, and restricted cash at beginning of period	7.5	47.7
Cash, cash equivalents, and restricted cash at end of period	$ 14.7	$ 17.1