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v3.22.2

Business Segments (Details) $ in Millions | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Jun. 30, 2022 USD ($) Segments | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($)
Business Segments [Line Items] |  |  |  |  |  |
Number of Reportable Segments | Segments |  |  |  | 2 |  |
Operating Revenue |  | $ 373.1 | $ 335.6 | $ 756.6 | $ 674.8 |
Net Income Attributable to ALLETE |  | 37.6 | 27.9 | 103.9 | 79.7 |
Assets |  | 6,839.0 |  | 6,839.0 |  | $ 6,435.0
New Energy |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
After Tax Impact for Purchase Price Accounting |  |  |  | 4.0 |  |
Business Combination, Acquisition Related Costs |  |  |  | $ 3.0 |  |
Regulated Operations [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Number of Operating Segments | Segments |  |  |  | 3 |  |
Operating Revenue |  | 308.7 | 290.4 | $ 637.7 | 583.4 |
Net Income Attributable to ALLETE |  | 29.6 | 21.5 | 81.1 | 66.5 |
Assets |  | 4,370.9 |  | 4,370.9 |  | 4,289.4
Regulated Operations [Member] | Residential [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 40.6 | 35.4 | 96.6 | 81.0 |
Regulated Operations [Member] | Commercial [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 44.4 | 40.7 | 92.7 | 80.4 |
Regulated Operations [Member] | Municipal [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 10.0 | 11.5 | 22.1 | 24.1 |
Regulated Operations [Member] | Industrial [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 150.6 | 139.1 | 298.4 | 268.1 |
Regulated Operations [Member] | Other Power Suppliers [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 36.9 | 37.3 | 77.9 | 75.7 |
Regulated Operations [Member] | Other [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 26.2 | 26.4 | 50.0 | 54.1 |
ALLETE Clean Energy [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 21.2 | 21.6 | 49.4 | 42.5 |
Net Income Attributable to ALLETE |  | 5.8 | 5.1 | 22.3 | 12.5 |
Assets |  | 1,834.9 |  | 1,834.9 |  | 1,719.4
ALLETE Clean Energy [Member] | Long-term PSA [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 18.9 | 18.7 | 44.3 | 36.8 |
ALLETE Clean Energy [Member] | Other [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue, Other Than Customer Revenue |  | 2.3 | 2.9 | 5.1 | 5.7 |
Corporate and Other [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 43.2 | 23.6 | 69.5 | 48.9 |
Net Income Attributable to ALLETE | [1] | 2.2 | 1.3 | 0.5 | 0.7 |
Assets |  | 633.2 |  | 633.2 |  | $ 426.2
Corporate and Other [Member] | Long-term Contract [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 21.4 | 21.4 | 44.0 | 43.1 |
Corporate and Other [Member] | Other [Member] |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | 7.3 | 2.2 | 11.0 | 5.8 |
Corporate and Other [Member] | Sale of Renewable Development Projects |  |  |  |  |  |
Business Segments [Line Items] |  |  |  |  |  |
Operating Revenue |  | $ 14.5 | $ 0.0 | $ 14.5 | $ 0.0 |
[1] | Net Income in 2022 includes $4.0 million after-tax of purchase price accounting adjustments and $3.0 million after-tax of transaction costs related to the acquisition of New Energy.

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