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v3.20.4

Long-Term Debt - Debt Outstanding, Issuances, and Redemptions (Details) $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2020 USD ($) number_of_interest_rate_swaps | Nov. 30, 2020 USD ($) | Oct. 31, 2020 USD ($) | Sep. 30, 2020 USD ($) | Aug. 31, 2020 USD ($) | May 31, 2020 USD ($) | Apr. 30, 2020 USD ($) | Dec. 31, 2020 USD ($) number_of_interest_rate_swaps | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jul. 12, 2018 number_of_interest_rate_swaps
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Total | $ 12,529.2 |  |  |  |  |  |  | $ 12,529.2 | $ 11,922.5 |  |
Integrys acquisition fair value adjustment | 8.4 |  |  |  |  |  |  | 8.4 | 14.3 |  |
Unamortized debt issuance costs | (65.2) |  |  |  |  |  |  | (65.2) | (52.9) |  |
Unamortized discount, net and other | (21.9) |  |  |  |  |  |  | (21.9) | (25.6) |  |
Long-term debt, including current portion | 12,450.5 |  |  |  |  |  |  | 12,450.5 | 11,858.3 |  |
Current portion of long-term debt | (777.7) |  |  |  |  |  |  | (777.7) | (686.9) |  |
Long-term debt | 11,672.8 |  |  |  |  |  |  | 11,672.8 | 11,171.4 |  |
Finance lease obligation | 63.4 |  |  |  |  |  |  | 63.4 | 45.9 |  |
Loss on debt extinguishment | 10.5 |  | $ 27.9 |  |  |  |  | 38.4 | 0.0 | $ 0.0 |
Future maturities of long-term debt outstanding |  |  |  |  |  |  |  |  |  |  |
2021 | 777.7 |  |  |  |  |  |  | 777.7 |  |  |
2022 | 83.3 |  |  |  |  |  |  | 83.3 |  |  |
2023 | 784.9 |  |  |  |  |  |  | 784.9 |  |  |
2024 | 613.7 |  |  |  |  |  |  | 613.7 |  |  |
2025 | 1,156.7 |  |  |  |  |  |  | 1,156.7 |  |  |
Thereafter | 9,112.9 |  |  |  |  |  |  | 9,112.9 |  |  |
Total | $ 12,529.2 |  |  |  |  |  |  | $ 12,529.2 | $ 11,922.5 |  |
WE |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 4.26% |  |  |  |  |  |  | 4.26% | 4.26% |  |
Unsecured debt | $ 2,785.0 |  |  |  |  |  |  | $ 2,785.0 | $ 2,785.0 |  |
WPS |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 4.04% |  |  |  |  |  |  | 4.04% | 4.04% |  |
Senior notes | $ 1,625.0 |  |  |  |  |  |  | $ 1,625.0 | $ 1,625.0 |  |
WG |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.65% |  |  |  |  |  |  | 3.65% | 3.65% |  |
Unsecured debt | $ 640.0 |  |  |  |  |  |  | $ 640.0 | $ 640.0 |  |
Integrys |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate |  |  |  |  |  |  |  |  | 4.17% |  |
Senior notes | $ 0.0 |  |  |  |  |  |  | $ 0.0 | $ 250.0 |  |
Integrys | 6.00% Integrys junior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 6.00% |  |  |  |  |  |  | 6.00% | 6.00% |  |
Unsecured debt | $ 400.0 |  |  |  |  |  |  | $ 400.0 | $ 400.0 |  |
Interest rate | 6.00% |  |  |  |  |  |  | 6.00% |  |  |
Basis points added to three-month LIBOR rate |  |  |  |  |  |  |  | 3.22% |  |  |
Integrys | 4.17% Integrys senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  | 4.17% |  |  |  |  |  |  |  |  |
Redemption of unsecured debt |  | $ 250.0 |  |  |  |  |  |  |  |  |
PGL |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.45% |  |  |  |  |  |  | 3.45% | 3.59% |  |
Secured debt | $ 1,670.0 |  |  |  |  |  |  | $ 1,670.0 | $ 1,520.0 |  |
PGL | 1.875% PGL series WW bonds |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  | 1.875% |  |  |  |  |  |
Redemption of secured debt |  |  |  |  | $ 50.0 |  |  |  |  |  |
PGL | 1.98% PGL series JJJ bonds |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  | 1.98% |  |  |  |  |  |  |  |  |
Issuance of debt |  | $ 200.0 |  |  |  |  |  |  |  |  |
NSG |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.81% |  |  |  |  |  |  | 3.81% | 3.81% |  |
Secured debt | $ 132.0 |  |  |  |  |  |  | $ 132.0 | $ 132.0 |  |
MERC |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.27% |  |  |  |  |  |  | 3.27% | 3.51% |  |
Senior notes | $ 170.0 |  |  |  |  |  |  | $ 170.0 | $ 120.0 |  |
MERC | 2.69% MERC senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  | 2.69% |  |  |  |
Issuance of debt |  |  |  |  |  |  | $ 50.0 |  |  |  |
MGU |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.18% |  |  |  |  |  |  | 3.18% | 3.51% |  |
Senior notes | $ 150.0 |  |  |  |  |  |  | $ 150.0 | $ 90.0 |  |
MGU | 2.69% MGU senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  |  | 2.69% |  |  |  |
Issuance of debt |  |  |  |  |  |  | $ 60.0 |  |  |  |
UMERC |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.26% |  |  |  |  |  |  | 3.26% | 3.26% |  |
Senior notes | $ 160.0 |  |  |  |  |  |  | $ 160.0 | $ 160.0 |  |
Bluewater Gas Storage |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.76% |  |  |  |  |  |  | 3.76% | 3.76% |  |
Senior notes | $ 117.8 |  |  |  |  |  |  | $ 117.8 | $ 120.3 |  |
ATC Holding LLC |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 4.05% |  |  |  |  |  |  | 4.05% | 4.05% |  |
Senior notes | $ 475.0 |  |  |  |  |  |  | $ 475.0 | $ 475.0 |  |
We Power |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 5.59% |  |  |  |  |  |  | 5.59% | 5.57% |  |
Secured debt | $ 970.8 |  |  |  |  |  |  | $ 970.8 | $ 1,005.2 |  |
WECC |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 6.94% |  |  |  |  |  |  | 6.94% | 6.94% |  |
Unsecured debt | $ 50.0 |  |  |  |  |  |  | $ 50.0 | $ 50.0 |  |
WECI Wind Holding I |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 2.75% |  |  |  |  |  |  | 2.75% |  |  |
Senior notes | $ 413.6 |  |  |  |  |  |  | $ 413.6 | $ 0.0 |  |
WECI Wind Holding I | 2.75% WECI Wind Holding I senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate | 2.75% |  |  |  |  |  |  | 2.75% |  |  |
Issuance of debt | $ 413.6 |  |  |  |  |  |  |  |  |  |
WEC Energy Group |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 2.03% |  |  |  |  |  |  | 2.03% | 3.47% |  |
Senior notes | $ 2,270.0 |  |  |  |  |  |  | $ 2,270.0 | $ 2,050.0 |  |
Current portion of long-term debt | 0.0 |  |  |  |  |  |  | 0.0 | (400.0) |  |
Long-term debt | 2,754.8 |  |  |  |  |  |  | 2,754.8 | 2,141.6 |  |
Loss on debt extinguishment |  |  |  |  |  |  |  | 38.4 | $ 0.0 | $ 0.0 |
Future maturities of long-term debt outstanding |  |  |  |  |  |  |  |  |  |  |
2021 | 0.0 |  |  |  |  |  |  | 0.0 |  |  |
2022 | 0.0 |  |  |  |  |  |  | 0.0 |  |  |
2023 | 700.0 |  |  |  |  |  |  | 700.0 |  |  |
2024 | 0.0 |  |  |  |  |  |  | 0.0 |  |  |
2025 | 420.0 |  |  |  |  |  |  | 420.0 |  |  |
Thereafter | $ 1,650.0 |  |  |  |  |  |  | $ 1,650.0 |  |  |
WEC Energy Group | WEC Energy Group junior notes due 2067 |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Weighted average interest rate | 3.65% |  |  |  |  |  |  | 3.65% | 4.50% |  |
Unsecured debt | $ 500.0 |  |  |  |  |  |  | $ 500.0 | $ 500.0 |  |
Interest rate | 2.33% |  |  |  |  |  |  | 2.33% | 4.02% |  |
WEC Energy Group | 6.20% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate | 6.20% |  |  |  |  |  |  | 6.20% |  |  |
WEC Energy Group | 2.45% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  |  |  | 2.45% |  |  |  |  |
Redemption of unsecured debt |  |  |  |  |  | $ 400.0 |  |  |  |  |
WEC Energy Group | 0.55% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  |  | 0.55% |  |  |  |  |  |  |
Issuance of debt |  |  |  | $ 700.0 |  |  |  |  |  |  |
WEC Energy Group | 1.375% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  | 1.375% |  |  |  |  |  |  |  |
Issuance of debt |  |  | $ 500.0 |  |  |  |  |  |  |  |
WEC Energy Group | 1.800% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  | 1.80% |  |  |  |  |  |  |  |
Issuance of debt |  |  | $ 450.0 |  |  |  |  |  |  |  |
WEC Energy Group | 3.375% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  | 3.375% |  |  |  |  |  |  |  |
Redemption of unsecured debt |  |  | $ 600.0 |  |  |  |  |  |  |  |
WEC Energy Group | 3.10% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Interest rate |  |  | 3.10% |  |  |  |  |  |  |  |
Redemption of unsecured debt |  |  | $ 350.0 |  |  |  |  |  |  |  |
WEC Energy Group | 3.55% WEC Energy Group senior notes |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Senior notes | $ 500.0 |  |  |  |  |  |  | $ 500.0 |  |  |
Interest rate | 3.55% |  |  |  |  |  |  | 3.55% |  |  |
Redemption of unsecured debt | $ 80.0 |  |  |  |  |  |  |  |  |  |
WEC Energy Group | Interest rate swaps |  |  |  |  |  |  |  |  |  |  |
Long-term debt |  |  |  |  |  |  |  |  |  |  |
Number of interest rate swaps executed | number_of_interest_rate_swaps | 2 |  |  |  |  |  |  | 2 |  |  | 2
Interest rate swap fixed interest rate | 4.9765% |  |  |  |  |  |  | 4.9765% |  |  |
Interest rate swap notional value | $ 250.0 |  |  |  |  |  |  | $ 250.0 |  |  |

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