v3.20.1

Revenue from contracts - Disaggregation of revenue (Details) $ in Millions | 3 Months Ended
--- | ---
Mar. 31, 2020 USD ($) segment | Mar. 31, 2019 USD ($)
Disaggregation of revenue |  |
Total revenue | $ 72.8 | $ 73.0
Number of reportable segments | segment | 4 |
Solid Fuel |  |
Disaggregation of revenue |  |
Total revenue | $ 23.4 | 19.8
Natural Gas |  |
Disaggregation of revenue |  |
Total revenue | 30.8 | 34.6
Hydroelectric |  |
Disaggregation of revenue |  |
Total revenue | 18.4 | 18.4
Corporate |  |
Disaggregation of revenue |  |
Total revenue | 0.2 | 0.2
Energy sales |  |
Disaggregation of revenue |  |
Project revenue | 40.7 | 37.0
Total revenue | 40.7 | 37.0
Energy sales | Solid Fuel |  |
Disaggregation of revenue |  |
Project revenue | 16.8 | 10.4
Energy sales | Natural Gas |  |
Disaggregation of revenue |  |
Project revenue | 6.2 | 9.0
Energy sales | Hydroelectric |  |
Disaggregation of revenue |  |
Project revenue | 17.7 | 17.6
Energy capacity revenue |  |
Disaggregation of revenue |  |
Project revenue | 28.0 | 30.2
Total revenue | 28.0 | 30.2
Energy capacity revenue | Solid Fuel |  |
Disaggregation of revenue |  |
Project revenue | 6.3 | 9.3
Energy capacity revenue | Natural Gas |  |
Disaggregation of revenue |  |
Project revenue | 21.7 | 20.9
Steam energy and capacity revenue |  |
Disaggregation of revenue |  |
Project revenue | 2.7 | 0.6
Steam energy and capacity revenue | Natural Gas |  |
Disaggregation of revenue |  |
Project revenue | 2.7 | 0.6
Waste heat revenue |  |
Disaggregation of revenue |  |
Project revenue | 0.3 |
Waste heat revenue | Solid Fuel |  |
Disaggregation of revenue |  |
Project revenue | 0.3 |
Ancillary and transmission services |  |
Disaggregation of revenue |  |
Project revenue | 1.4 | 5.1
Ancillary and transmission services | Natural Gas |  |
Disaggregation of revenue |  |
Project revenue | 0.7 | 4.3
Ancillary and transmission services | Hydroelectric |  |
Disaggregation of revenue |  |
Project revenue | 0.7 | 0.8
Asset management and operation |  |
Disaggregation of revenue |  |
Project revenue | 0.2 | 0.2
Asset management and operation | Solid Fuel |  |
Disaggregation of revenue |  |
Project revenue |  | 0.1
Asset management and operation | Natural Gas |  |
Disaggregation of revenue |  |
Project revenue |  | (0.1)
Asset management and operation | Corporate |  |
Disaggregation of revenue |  |
Project revenue | 0.2 | 0.2
Miscellaneous revenue |  |
Disaggregation of revenue |  |
Miscellaneous revenue | (0.5) | (0.1)
Total revenue | 4.1 | 5.8
Miscellaneous revenue | Natural Gas |  |
Disaggregation of revenue |  |
Miscellaneous revenue | $ (0.5) | $ (0.1)

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