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v3.20.4

Investments in Unconsolidated Affiliates (Narrative) (Details) $ in Millions | 12 Months Ended |
--- | --- | ---
Dec. 31, 2020 USD ($) asset MW | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Jun. 30, 2019
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Distributions from equity investments | $ 37 | $ 55 | $ 108 |
Distributions from equity investments, return of capital | $ 133 | 11 | 137 |
Electric Utilities and Infrastructure | DATC |  |  |  |
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Ownership interest | 50.00% |  |  |
Electric Utilities and Infrastructure | Pioneer |  |  |  |
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Ownership interest | 50.00% |  |  |
Commercial Renewables | Non-consolidated VIEs |  |  |  |
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Number of cell projects | asset | 70 |  |  |
Capacity of assets | MW | 43 |  |  |
Commercial Renewables | DS Cornerstone |  |  |  |
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Ownership interest | 26.00% |  |  | 50.00%
Other | NMC |  |  |  |
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Ownership interest | 17.50% |  |  |
Board representation and voting rights, ownership percentage | 25.00% |  |  |
Piedmont |  |  |  |
Investments In Unconsolidated Affiliates [Line Items] |  |  |  |
Distributions from equity investments | $ 2 | 1 | 1 |
Distributions from equity investments, return of capital | $ 2 | $ 4 | $ 3 |

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