v3.25.4

Variable Interest Entities (Narrative) (Details) $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2025 USD ($) MW | Dec. 31, 2025 USD ($) MW | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Variable Interest Entity [Line Items] |  |  |  |
Deemed contribution from sale of membership interest |  | $ 35 | $ 0 | $ 0
Investments |  | 61 | 64 |
Class A - Tax Equity Membership |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Proceeds from the sale of membership interests in VIEs |  | $ 15 | 0 | $ 86
NWO Wind Equity Holdings |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Proceeds from the sale of membership interests in VIEs | $ 36 |  |  |
Delta Township, Michigan, Solar Project |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Proceeds from the sale of membership interests in VIEs | $ 8 |  |  |
Variable Interest Entity, Primary Beneficiary | NWO Holdco |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Nameplate capacity (in MW) | MW |  | 100 |  |
Variable Interest Entity, Primary Beneficiary | BG Solar Holdings |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Nameplate capacity (in MW) | MW |  | 200 |  |
Renewablee Energy Purchase AGreement Term |  | 15 years |  |
Variable Interest Entity, Primary Beneficiary | NWO Wind Equity Holdings |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest | 50.00% |  |  |
Variable Interest Entity, Primary Beneficiary | Delta Township, Michigan, Solar Project |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest | 50.00% |  |  |
Nameplate capacity (in MW) | MW | 24 |  |  |
Variable Interest Entity, Not Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Investments |  | $ 54 | $ 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% |  |

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