Schedule I - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2024	Dec. 31, 2023
Future maturities of long-term debt outstanding
2025	$ 1,729.0
2026	1,519.4
2027	2,137.3
2028	2,303.2
2029	2,643.4
Thereafter	8,691.6
Long-term debt	17,178.1	$ 15,366.9
WEC Energy Group
Future maturities of long-term debt outstanding
2025	620.0
2026	1,350.0
2027	1,762.5
2028	950.0
2029	862.5
Thereafter	1,250.0
Total	6,795.0
Long-term debt	6,135.4	$ 5,192.8
WEC Energy Group \| WECC \| Support agreement related to WECC debt
Future maturities of long-term debt outstanding
Long-term debt	$ 50.0

Face (par) amount of debt instrument at time of issuance.

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