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v3.25.3

Variable Interest Entities (Narrative) (Details) $ in Millions |  |  |  |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | --- | --- | --- | ---
Jun. 18, 2025 USD ($) | May 31, 2025 USD ($) | Feb. 03, 2025 USD ($) | Jan. 15, 2025 USD ($) | Sep. 30, 2025 USD ($) Rate MW | Mar. 31, 2025 USD ($) | Sep. 30, 2024 USD ($) | Sep. 30, 2025 USD ($) Rate MW | Sep. 30, 2024 USD ($)
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |
Wind Power Purchase Agreement, Purchase Percentage | Rate |  |  |  |  | 100.00% |  |  | 100.00% |
Payments to Acquire Assets, Investing Activities | $ | $ 262.4 | $ 141.4 | $ 217.6 | $ 336.6 |  |  |  |  |
Income Taxes | $ |  |  |  |  | $ 20.6 |  | $ 15.9 | $ 150.1 | $ 109.5
Contributions from NIPSCO minority interest holders | $ |  |  |  |  | 11.0 |  | 39.8 | 145.3 | 99.5
Payments to Noncontrolling Interests | $ |  |  |  |  | $ 11.1 | $ 32.0 | $ 11.8 | $ 55.5 | $ 32.0
Rosewater |  |  |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |
Nameplate Capacity | MW |  |  |  |  | 102 |  |  | 102 |
Indiana Crossroads Wind |  |  |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |
Nameplate Capacity | MW |  |  |  |  | 302 |  |  | 302 |
Indiana Crossroads Solar |  |  |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |
Nameplate Capacity | MW |  |  |  |  | 200 |  |  | 200 |
Dunns Bridge I |  |  |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |  |  |
Nameplate Capacity | MW |  |  |  |  | 265 |  |  | 265 |

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