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v3.21.1

Variable Interest Entities (Narrative) (Details) $ in Millions | 1 Months Ended | 3 Months Ended |
--- | --- | --- | ---
Sep. 30, 2020 | Jul. 31, 2020 MW | Mar. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Variable Interest Entity [Line Items] |  |  |  |
Investments |  |  | $ 72 | $ 70
Variable Interest Entity, Primary Beneficiary | Aviator Wind |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Ownership interest | 51.00% | 51.00% |  |
Nameplate capacity (in MW) | MW |  | 525 |  |
Variable Interest Entity, Primary Beneficiary | Aviator Wind Class B Membership |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Noncontrolling ownership interest |  | 49.00% |  |
Variable Interest Entity, Not Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Investments |  |  | $ 72 | $ 70
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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