v3.19.3.a.u2

Acquisitions and divestments - AltaGas acquisition (Details) $ in Millions | Aug. 13, 2019 USD ($) MWh Plant MW | Dec. 31, 2019 USD ($) | Jun. 18, 2018
--- | --- | --- | ---
Asset acquisitions |  |  |
Percentage of equity method ownership interest |  |  | 100.00%
AltaGas Acquisition [Member] | Craven | CMS Energy [Member] |  |  |
Asset acquisitions |  |  |
Percentage of interest | 50.00% |  |
AltaGas Acquisition [Member] | Grayling | CMS Energy [Member] |  |  |
Asset acquisitions |  |  |
Percentage of interest | 50.00% |  |
AltaGas Acquisition [Member] | Grayling | Fortistar [Member] |  |  |
Asset acquisitions |  |  |
Percentage of interest | 20.00% |  |
AltaGas Acquisition [Member] |  |  |
Asset acquisitions |  |  |
Number Of Plants Acquired | Plant | 2 |  |
Purchase price | $ 18.7 |  |
Acquisition related transaction cost | $ 0.2 |  |
Equity in earnings from unconsolidated affiliates |  | $ 1.0 |
Equity method distributions |  | $ 0.9 |
AltaGas Acquisition [Member] | Minimum |  |  |
Asset acquisitions |  |  |
Percentage of equity method ownership interest | 5.00% |  |
AltaGas Acquisition [Member] | Maximum |  |  |
Asset acquisitions |  |  |
Percentage of equity method ownership interest | 50.00% |  |
AltaGas Acquisition [Member] | Craven |  |  |
Asset acquisitions |  |  |
Plant Capacity | MWh | 48 |  |
Interest acquired in the plant | 50.00% |  |
AltaGas Acquisition [Member] | Grayling |  |  |
Asset acquisitions |  |  |
Number Of Plants Acquired | MW | 37 |  |
Interest acquired in the plant | 30.00% |  |

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