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v3.22.4

Commitments and Contingencies - Narrative (Details) $ in Millions |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jan. 03, 2023 USD ($) | Jun. 30, 2022 MWh | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Other Commitments [Line Items] |  |  |  |  |
Capacity and energy requirement costs |  |  | $ 13.1 | $ 11.5 | $ 11.3
Coal purchase commitment costs |  |  | 45.1 | 40.4 | 37.9
Land easement non-lease payments expense |  |  | 1.4 | $ 1.3 | $ 1.3
OTP |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |
Wind farm, megawatts | MWh |  | 62.4 |  |  |
OTP | Subsequent Event |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |
Payments to acquire wind farm | $ 50.6 |  |  |  |
OTP | Federal Energy Regulatory Commission |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |
Estimated liability of refund obligation |  |  | 2.6 |  |
OTP | Construction Programs |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |
Long-term purchase commitment, amount |  |  | 21.5 |  |
OTP | OTP Land Easements |  |  |  |  |
Other Commitments [Line Items] |  |  |  |  |
Long-term purchase commitment, amount |  |  | $ 33.1 |  |

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