v3.20.2

Revenue from contracts (Tables) | 9 Months Ended
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Sep. 30, 2020
Revenue from contracts |
Schedule of disaggregation of revenue | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended September 30, 2020
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  | ​ |  | Consolidated
​ | ​ | Solid Fuel | ​ | Natural Gas | ​ | Hydroelectric | ​ | Corporate | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 14.3 | ​ | $ | 7.5 | ​ | $ | 8.5 | ​ | $ | — | ​ | $ | 30.3
Energy capacity revenue | ​ |  | 12.2 | ​ | ​ | 17.5 | ​ | ​ | — | ​ |  | — | ​ |  | 29.7
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | 2.5 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 2.5
Waste heat revenue | ​ | ​ | 0.1 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.1
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 0.7 | ​ | ​ | 0.7 | ​ | ​ | — | ​ | ​ | 1.4
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.2 | ​ | ​ | 0.2
Miscellaneous revenue | ​ | ​ | 0.1 | ​ | ​ | 0.9 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 1.0
​ | ​ |  | 26.7 | ​ |  | 29.1 | ​ |  | 9.2 | ​ |  | 0.2 | ​ |  | 65.2
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended September 30, 2019
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  |  | ​ |  |  | Consolidated
​ | ​ | ​ | Solid Fuel | ​ | ​ | Natural Gas | ​ | ​ | Hydroelectric | ​ | ​ | Corporate | ​ | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 12.4 | ​ | $ | 7.7 | ​ | $ | 9.1 | ​ | $ | — | ​ | $ | 29.2
Energy capacity revenue | ​ |  | 13.7 | ​ |  | 24.3 | ​ |  | — | ​ |  | — | ​ |  | 38.0
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | 0.2 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.2
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 2.8 | ​ | ​ | 0.6 | ​ | ​ | — | ​ | ​ | 3.4
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.2 | ​ | ​ | 0.2
Miscellaneous revenue | ​ | ​ | — | ​ | ​ | 0.1 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.1
​ | ​ |  | 26.1 | ​ |  | 35.1 | ​ |  | 9.7 | ​ |  | 0.2 | ​ |  | 71.1
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nine Months Ended September 30, 2020
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  | ​ |  | Consolidated
​ | ​ | Solid Fuel | ​ | Natural Gas | ​ | Hydroelectric | ​ | Corporate | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 40.6 | ​ | $ | 18.4 | ​ | $ | 43.1 | $ | ​ | — | ​ | $ | 102.1
Energy capacity revenue | ​ |  | 26.2 | ​ | ​ | 58.6 | ​ | ​ | — | ​ | ​ | — | ​ |  | 84.8
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | 6.8 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 6.8
Waste heat revenue | ​ | ​ | 0.5 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.5
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 2.2 | ​ | ​ | 2.4 | ​ | ​ | — | ​ | ​ | 4.6
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.7 | ​ | ​ | 0.7
Miscellaneous revenue | ​ | ​ | 0.1 | ​ | ​ | 0.7 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.8
​ | ​ |  | 67.4 | ​ |  | 86.7 | ​ |  | 45.5 | ​ |  | 0.7 | ​ |  | 200.3
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Nine Months Ended September 30, 2019
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  |  | ​ |  |  | Consolidated
​ | ​ | ​ | Solid Fuel | ​ | ​ | Natural Gas | ​ | ​ | Hydroelectric | ​ | ​ | Corporate | ​ | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 30.7 | ​ | $ | 23.6 | ​ | $ | 48.4 | ​ | $ | — | ​ | $ | 102.7
Energy capacity revenue | ​ |  | 33.7 | ​ |  | 66.1 | ​ |  | — | ​ |  | — | ​ |  | 99.8
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | 0.1 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.1
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 10.3 | ​ | ​ | 2.2 | ​ | ​ | — | ​ | ​ | 12.5
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.7 | ​ | ​ | 0.7
Miscellaneous revenue | ​ | ​ | 0.1 | ​ | ​ | (0.5) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (0.4)
​ | ​ |  | 64.5 | ​ |  | 99.6 | ​ |  | 50.6 | ​ |  | 0.7 | ​ |  | 215.4

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- Definition Tabular disclosure of disaggregation of revenue into categories depicting how nature, amount, timing, and uncertainty of revenue and cash flows are affected by economic factor. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130545-203045 + Details
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