CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Current assets
Cash and cash equivalents	$ 38.9	$ 42.9
Accounts receivable and unbilled revenues, net of reserves of $190.7 and $193.5, respectively	1,557.0	1,503.2
Materials, supplies, and inventories	608.6	775.2
Prepaid taxes	143.0	173.9
Other prepayments	70.9	76.8
Other	186.2	223.7
Current assets	2,604.6	2,795.7
Long-term assets
Property, plant, and equipment, net of accumulated depreciation and amortization of $11,275.0 and $11,073.1, respectively	31,729.8	31,581.5
Regulatory assets (March 31, 2024 and December 31, 2023 include $84.1 and $85.9, respectively, related to WEPCo Environmental Trust)	3,247.0	3,249.8
Equity investment in transmission affiliates	2,027.1	2,005.9
Goodwill	3,052.8	3,052.8
Pension and OPEB assets	883.9	870.9
Other	382.0	383.1
Long-term assets	41,322.6	41,144.0
Total assets	43,927.2	43,939.7
Current liabilities
Short-term debt	2,574.2	2,020.9
Current portion of long-term debt (March 31, 2024 and December 31, 2023 include $9.0, related to WEPCo Environmental Trust)	640.5	1,264.2
Accounts payable	640.9	896.6
Other	854.1	933.1
Current liabilities	4,709.7	5,114.8
Long-term liabilities
Long-term debt (March 31, 2024 and December 31, 2023 include $85.4 and $85.3, respectively, related to WEPCo Environmental Trust)	15,375.8	15,512.8
Deferred income taxes	5,120.0	4,918.5
Deferred revenue, net	351.1	356.4
Regulatory liabilities	3,730.2	3,697.7
Intangible liabilities	581.4	594.8
Environmental remediation liabilities	448.9	463.7
AROs	377.7	374.2
Other	806.3	835.3
Long-term liabilities	26,791.4	26,753.4
Commitments and contingencies (Note 20)
Common shareholders' equity
Common stock – $0.01 par value; 325,000,000 shares authorized; 315,822,587 and 315,434,531 shares outstanding, respectively	3.2	3.2
Additional paid in capital	4,145.7	4,115.9
Retained earnings	7,971.6	7,612.8
Accumulated other comprehensive loss	(7.8)	(7.7)
Common shareholders' equity	12,112.7	11,724.2
Preferred stock of subsidiary	30.4	30.4
Noncontrolling interests	283.0	316.9
Total liabilities and equity	$ 43,927.2	$ 43,939.7