Schedule I - Cash Dividends Received from Subsidiaries (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
WECI
Notes to parent company financial statements
Return of capital from subsidiaries	$ 843.9	$ 171.6	$ 363.7
Wispark
Notes to parent company financial statements
Return of capital from subsidiaries	2.7	3.6	9.2
WEC Energy Group
Notes to parent company financial statements
Cash dividends received from subsidiaries	792.4	935.7	1,035.6
Return of capital from subsidiaries	846.6	175.2	372.9
WEC Energy Group \| WE
Notes to parent company financial statements
Cash dividends received from subsidiaries	240.0	370.0	630.0
WEC Energy Group \| We Power
Notes to parent company financial statements
Cash dividends received from subsidiaries	225.3	192.8	158.5
WEC Energy Group \| WECI
Notes to parent company financial statements
Cash dividends received from subsidiaries	127.2	93.7	87.7
WEC Energy Group \| ATC Holding LLC
Notes to parent company financial statements
Cash dividends received from subsidiaries	104.6	86.8	74.9
WEC Energy Group \| WG
Notes to parent company financial statements
Cash dividends received from subsidiaries	80.0	171.0	60.0
WEC Energy Group \| UMERC
Notes to parent company financial statements
Cash dividends received from subsidiaries	15.0	21.0	17.0
WEC Energy Group \| Wispark
Notes to parent company financial statements
Cash dividends received from subsidiaries	$ 0.3	$ 0.4	$ 7.5

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Reference 5: http://www.xbrl.org/2003/role/disclosureRef
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Amount of distribution received from equity method investee for return of investment, classified as investing activities. Excludes distribution for return on investment, classified as operating activities.

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