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v3.19.3.a.u2

Long-Term Debt (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 USD ($) number_of_interest_rate_swaps | Dec. 31, 2018 USD ($)
Debt Instrument [Line Items] |  |
Total | $ 11,922.5 | $ 10,387.6
Integrys acquisition fair value adjustment | 14.3 | 20.6
Unamortized debt issuance costs | (52.9) | (44.7)
Unamortized discount, net and other | (25.6) | (27.8)
Long-term debt, including current portion | 11,858.3 | 10,335.7
Current portion of long-term debt | (686.9) | (360.1)
Total long-term debt | 11,171.4 | 9,975.6
Finance lease obligation | 45.9 | 23.3
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 |
Total | $ 11,922.5 | $ 10,387.6
WE |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 4.26% | 4.50%
Unsecured debt | $ 2,785.0 | $ 2,735.0
WE | WE Debentures (unsecured), 2.05% due 2024 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 2.05% |
Proceeds from issuance of debt | $ 300.0 |
WE | WE Debentures (unsecured), 4.25% due 2019 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 4.25% |
Repayments of Unsecured Debt | $ 250.0 |
WPS |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 4.04% | 4.21%
Senior notes | $ 1,625.0 | $ 1,325.0
WPS | WPS Senior Notes (unsecured), 3.30% due 2049 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 3.30% |
Proceeds from issuance of debt | $ 300.0 |
WG |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.65% | 4.04%
Unsecured debt | $ 640.0 | $ 490.0
WG | WG Debentures (unsecured), 2.38% due 2024 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 2.38% |
Proceeds from issuance of debt | $ 150.0 |
Integrys Holding Inc |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 4.17% | 4.17%
Senior notes | $ 250.0 | $ 250.0
Integrys Holding Inc | Integrys Junior Notes (unsecured), 6.00% due 2073 |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 6.00% | 6.00%
Unsecured debt | $ 400.0 | $ 400.0
Debt instrument interest rate stated percentage rate | 6.00% |
Debt Instrument, Basis Spread on Variable Rate | 3.22% |
PGL |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.59% | 3.88%
Secured debt | $ 1,520.0 | $ 1,195.0
PGL | PGL Series WW Bonds (secured), 1.875% due 2033 |  |
Debt Instrument [Line Items] |  |
Secured debt | $ 50.0 |
Debt instrument interest rate stated percentage rate | 1.875% |
PGL | PGL Series GGG (secured), 2.96% due 2029 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 2.96% |
Proceeds from issuance of debt | $ 275.0 |
PGL | PGL First and Refunding Mortgage Bonds (secured), 4.63% due 2019 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 4.63% |
Repayments of Secured Debt | $ 75.0 |
PGL | PGL Series HHH (secured), 2.64% due 2024 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 2.64% |
Proceeds from issuance of debt | $ 75.0 |
PGL | PGL Series III (secured), 3.06% due 2031 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 3.06% |
Proceeds from issuance of debt | $ 50.0 |
NSG |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.81% | 3.81%
Secured debt | $ 132.0 | $ 132.0
MERC |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.51% | 3.51%
Senior notes | $ 120.0 | $ 120.0
MGU |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.51% | 3.51%
Senior notes | $ 90.0 | $ 90.0
UMERC |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.26% |
Senior notes | $ 160.0 | $ 0.0
UMERC | UMERC Senior Notes (unsecured), 3.26% due 2029 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 3.26% |
Proceeds from issuance of debt | $ 160.0 |
Bluewater Gas Storage, LLC |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.76% | 3.76%
Senior notes | $ 120.3 | $ 122.7
ATC Holding LLC |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 4.05% | 4.34%
Senior notes | $ 475.0 | $ 240.0
ATC Holding LLC | ATC Holding Senior Notes (unsecured), 3.75% due 2029 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 3.75% |
Proceeds from issuance of debt | $ 235.0 |
We Power |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 5.57% | 5.56%
Secured debt | $ 1,005.2 | $ 1,037.9
WECC |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 6.94% | 6.94%
Unsecured debt | $ 50.0 | $ 50.0
WEC Energy Group |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 3.47% | 3.54%
Senior notes | $ 2,050.0 | $ 1,700.0
Current portion of long-term debt | (400.0) | 0.0
Total long-term debt | 2,141.6 | $ 2,190.8
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 |
WEC Energy Group | WEC Energy Group senior notes (unsecured), 6.20% due 2033 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 6.20% |
WEC Energy Group | WEC Energy Group Junior Notes (unsecured), 3.53% due 2067 |  |
Debt Instrument [Line Items] |  |
Weighted Average Interest Rate | 4.50% | 4.85%
Unsecured debt | $ 500.0 | $ 500.0
Debt instrument interest rate stated percentage rate | 4.02% | 4.73%
WEC Energy Group | WEC Senior Notes (unsecured), 3.10% due 2022 |  |
Debt Instrument [Line Items] |  |
Debt instrument interest rate stated percentage rate | 3.10% |
Proceeds from issuance of debt | $ 350.0 |
WEC Energy Group | Interest rate swaps |  |
Debt Instrument [Line Items] |  |
Number of interest rate swaps executed | number_of_interest_rate_swaps | 2 |
Interest rate swap fixed interest rate | 4.9765% |
Interest rate swap notional value | $ 250.0 |

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