v3.20.2

Revenue from contracts - Disaggregation of revenue (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2020 USD ($) | Jun. 30, 2019 USD ($) | Jun. 30, 2020 USD ($) segment | Jun. 30, 2019 USD ($)
Disaggregation of revenue |  |  |  |
Total revenue | $ 62.3 | $ 71.3 | $ 135.0 | $ 144.3
Number of reportable segments | segment |  |  | 4 |
Solid Fuel |  |  |  |
Disaggregation of revenue |  |  |  |
Total revenue | 17.3 | 18.6 | $ 40.6 | 38.3
Natural Gas |  |  |  |
Disaggregation of revenue |  |  |  |
Total revenue | 26.9 | 30.0 | 57.7 | 64.5
Hydroelectric |  |  |  |
Disaggregation of revenue |  |  |  |
Total revenue | 17.9 | 22.5 | 36.2 | 41.0
Corporate |  |  |  |
Disaggregation of revenue |  |  |  |
Total revenue | 0.2 | 0.2 | 0.5 | 0.5
Energy sales |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 31.1 | 36.5 | 71.7 | 73.5
Total revenue | 31.1 | 36.5 | 71.7 | 73.5
Energy sales | Solid Fuel |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 9.4 | 7.9 | 26.1 | 18.2
Energy sales | Natural Gas |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 4.8 | 6.9 | 11.0 | 15.9
Energy sales | Hydroelectric |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 16.9 | 21.7 | 34.6 | 39.4
Energy capacity revenue |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 27.1 | 31.6 | 55.1 | 61.8
Total revenue | 27.1 | 31.6 | 55.1 | 61.8
Energy capacity revenue | Solid Fuel |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 7.8 | 10.7 | 14.1 | 20.0
Energy capacity revenue | Natural Gas |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 19.3 | 20.9 | 41.0 | 41.8
Steam energy and capacity revenue |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 1.8 | (0.7) | 4.3 | (0.1)
Steam energy and capacity revenue | Natural Gas |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 1.8 | (0.7) | 4.3 | (0.1)
Waste heat revenue |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 0.1 |  | 0.4 |
Waste heat revenue | Solid Fuel |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 0.1 |  | 0.4 |
Ancillary and transmission services |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 0.2 | 4.0 | 0.4 | 8.9
Ancillary and transmission services | Natural Gas |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 0.2 | 3.2 | 0.4 | 7.3
Ancillary and transmission services | Hydroelectric |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue |  | 0.8 |  | 1.6
Asset management and operation |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 0.2 | 0.2 | 0.5 | 0.5
Asset management and operation | Corporate |  |  |  |
Disaggregation of revenue |  |  |  |
Project revenue | 0.2 | 0.2 | 0.5 | 0.5
Miscellaneous revenue |  |  |  |
Disaggregation of revenue |  |  |  |
Miscellaneous revenue | 1.8 | (0.3) | 2.6 | (0.3)
Total revenue | 4.1 | 3.2 | 8.2 | 9.0
Miscellaneous revenue | Solid Fuel |  |  |  |
Disaggregation of revenue |  |  |  |
Miscellaneous revenue |  |  |  | 0.1
Miscellaneous revenue | Natural Gas |  |  |  |
Disaggregation of revenue |  |  |  |
Miscellaneous revenue | 0.8 | $ (0.3) | 1.0 | $ (0.4)
Miscellaneous revenue | Hydroelectric |  |  |  |
Disaggregation of revenue |  |  |  |
Miscellaneous revenue | $ 1.0 |  | $ 1.6 |

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- Definition Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 30 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8906-108599 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 40 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9031-108599 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 41 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9038-108599 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 32 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8933-108599 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130543-203045 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 22 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e8736-108599 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 280 -SubTopic 10 -Section 50 -Paragraph 42 -URI http://asc.fasb.org/extlink&oid=120311839&loc=d3e9054-108599 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -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 Reference 11: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 924 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 11.L) -URI http://asc.fasb.org/extlink&oid=6472922&loc=d3e499488-122856 + Details
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