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v3.25.3

Variable Interest Entities (Narrative) (Details) $ in Millions | 1 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2025 USD ($) MW | Sep. 30, 2025 USD ($) | Sep. 30, 2024 USD ($) | Dec. 31, 2024 USD ($)
Variable Interest Entity [Line Items] |  |  |  |
Proceeds from the sale of membership interests in VIEs |  | $ 44 | $ 0 |
Securitization bonds |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Total principal amount outstanding |  | 600 |  | $ 700
Variable Interest Entity, Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Regulatory asset |  | 580 |  | 666
Variable Interest Entity, Not Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Investments |  | $ 59 |  | $ 64
Variable Interest Entity, Not Primary Beneficiary | T.E.S. Filer City |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest |  | 50.00% |  |
Variable Interest Entity, Not Primary Beneficiary | Grayling |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest |  | 50.00% |  |
Variable Interest Entity, Not Primary Beneficiary | Genesee |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest |  | 50.00% |  |
Variable Interest Entity, Not Primary Beneficiary | Craven |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest |  | 50.00% |  |
NWO Wind Equity Holdings |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Proceeds from the sale of membership interests in VIEs | $ 36 |  |  |
NWO Wind Equity Holdings | Variable Interest Entity, Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest | 50.00% |  |  |
NWO Holdco | Variable Interest Entity, Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Nameplate capacity (in MW) | MW | 100 |  |  |
Delta Township, Michigan, Solar Project |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Proceeds from the sale of membership interests in VIEs | $ 8 |  |  |
Delta Township, Michigan, Solar Project | Variable Interest Entity, Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest | 50.00% |  |  |
Nameplate capacity (in MW) | MW | 24 |  |  |

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