Schedule I - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Future maturities of long-term debt outstanding
2022	$ 91.0
2023	793.8
2024	1,222.7
2025	865.9
2026	104.2
Thereafter	10,575.0
Long-term debt	13,472.4	$ 11,672.8
WEC Energy Group
Future maturities of long-term debt outstanding
2022	0.0
2023	700.0
2024	600.0
2025	120.0
2026	0.0
Thereafter	2,150.0
Total	3,570.0
Long-term debt	3,549.8	$ 2,754.8
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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