Schedule I - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Future maturities of long-term debt outstanding
2021	$ 777.7
2022	83.3
2023	784.9
2024	613.7
2025	1,156.7
Thereafter	9,112.9
Long-term debt	11,672.8	$ 11,171.4
WEC Energy Group
Future maturities of long-term debt outstanding
2021	0.0
2022	0.0
2023	700.0
2024	0.0
2025	420.0
Thereafter	1,650.0
Total	2,770.0
Long-term debt	2,754.8	$ 2,141.6
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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