New Accounting Pronouncements (Details) - USD ($) $ in Millions	Dec. 31, 2023	Aug. 15, 2023	Jul. 01, 2023	Dec. 31, 2022	Nov. 15, 2021
WEC Energy Group | WEC Energy Group junior notes due 2067
Long-term debt
Unsecured debt	$ 500.0	$ 500.0	$ 500.0	$ 500.0	$ 500.0