Schedule I - Statements of Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Statements of comprehensive income
Net income attributed to common shareholders	$ 1,527.2	$ 1,331.7	$ 1,408.1
Other comprehensive loss, net of tax	(0.1)	(0.9)	(3.6)
Derivatives accounted for as cash flow hedges
Reclassification of realized derivative gains to net income, net of tax	(0.3)	(0.3)	(0.3)
Defined benefit plans
Pension and OPEB adjustments arising during the period, net of tax	0.1	(0.6)	(3.5)
Amortization of pension and OPEB costs included in net periodic benefit cost, net of tax	0.1	0.0	0.2
Defined benefit plans, net	0.2	(0.6)	(3.3)
WEC Energy Group
Statements of comprehensive income
Net income attributed to common shareholders	1,527.2	1,331.7	1,408.1
Other comprehensive income (loss) from subsidiaries, net of tax	0.1	(0.5)	(2.7)
Other comprehensive loss, net of tax	(0.1)	(0.9)	(3.6)
Comprehensive income attributed to common shareholders	1,527.1	1,330.8	1,404.5
WEC Energy Group | Derivatives accounted for as cash flow hedges
Derivatives accounted for as cash flow hedges
Reclassification of realized derivative gains to net income, net of tax	(0.3)	(0.3)	(0.3)
WEC Energy Group | Defined benefit plans
Defined benefit plans
Pension and OPEB adjustments arising during the period, net of tax	0.0	(0.2)	(0.8)
Amortization of pension and OPEB costs included in net periodic benefit cost, net of tax	0.1	0.1	0.2
Defined benefit plans, net	$ 0.1	$ (0.1)	$ (0.6)