Schedule I - Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Future maturities of long-term debt outstanding
2020	$ 686.9
2021	1,338.8
2022	390.8
2023	42.8
2024	570.0
Thereafter	8,893.2
Long-term debt	11,171.4	$ 9,975.6
WEC Energy Group
Future maturities of long-term debt outstanding
2020	400.0
2021	600.0
2022	350.0
2023	0.0
2024	0.0
Thereafter	1,200.0
Total	2,550.0
Long-term debt	2,141.6	$ 2,190.8
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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