Schedule I Statement of Comprehensive Income - Taxes (Details) - WEC Energy Group - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Statements of comprehensive income
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	$ 1,303.9	$ 1,197.2	$ 1,132.5
Cash flow hedges
Statements of comprehensive income
Other Comprehensive Income (Loss), Tax, Portion Attributable to Parent	$ 0.2	$ (1.6)	$ (1.3)

Amount after tax of other comprehensive income (loss) attributable to parent entity.

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