v3.20.2

Revenue from contracts | 6 Months Ended
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Jun. 30, 2020
Revenue from contracts |
Revenue from contracts | 2. Revenue from contracts ​ Disaggregation of revenue ​ We have four reportable segments: Solid Fuel, Natural Gas, Hydroelectric and Corporate. We revised our reportable business segments in the fourth quarter of 2019 as the result of recent asset acquisitions, PPA expirations and project decommissioning, and in order to align with changes to management’s structure, resource allocation and performance assessment in making decisions regarding our operations. Segment information for the comparative 2019 period has been revised to conform to the new segment presentation. Each segment contains various power generation projects and performance obligations as described above. For more detailed information about reportable segments, see Note 12, Segment and geographical information. Revenue by segment consists of the following: ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, 2020
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  | ​ |  | Consolidated
​ | ​ | Solid Fuel | ​ | Natural Gas | ​ | Hydroelectric | ​ | Corporate | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 9.4 | ​ | $ | 4.8 | ​ | $ | 16.9 | ​ | $ | — | ​ | $ | 31.1
Energy capacity revenue | ​ |  | 7.8 | ​ | ​ | 19.3 | ​ | ​ | — | ​ |  | — | ​ |  | 27.1
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | 1.8 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 1.8
Waste heat revenue | ​ | ​ | 0.1 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.1
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 0.2 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.2
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.2 | ​ | ​ | 0.2
Miscellaneous revenue | ​ | ​ | — | ​ | ​ | 0.8 | ​ | ​ | 1.0 | ​ | ​ | — | ​ | ​ | 1.8
​ | ​ |  | 17.3 | ​ |  | 26.9 | ​ |  | 17.9 | ​ |  | 0.2 | ​ |  | 62.3
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended June 30, 2019
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  |  | ​ |  |  | Consolidated
​ | ​ | ​ | Solid Fuel | ​ | ​ | Natural Gas | ​ | ​ | Hydroelectric | ​ | ​ | Corporate | ​ | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 7.9 | ​ | $ | 6.9 | ​ | $ | 21.7 | ​ | $ | — | ​ | $ | 36.5
Energy capacity revenue | ​ |  | 10.7 | ​ |  | 20.9 | ​ |  | — | ​ |  | — | ​ |  | 31.6
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | (0.7) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (0.7)
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 3.2 | ​ | ​ | 0.8 | ​ | ​ | — | ​ | ​ | 4.0
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.2 | ​ | ​ | 0.2
Miscellaneous revenue | ​ | ​ | — | ​ | ​ | (0.3) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (0.3)
​ | ​ |  | 18.6 | ​ |  | 30.0 | ​ |  | 22.5 | ​ |  | 0.2 | ​ |  | 71.3
​ ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Six Months Ended June 30, 2020
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  | ​ |  | Consolidated
​ | ​ | Solid Fuel | ​ | Natural Gas | ​ | Hydroelectric | ​ | Corporate | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 26.1 | ​ | $ | 11.0 | ​ | $ | 34.6 | $ | ​ | — | ​ | $ | 71.7
Energy capacity revenue | ​ |  | 14.1 | ​ | ​ | 41.0 | ​ | ​ | — | ​ | ​ | — | ​ |  | 55.1
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | 4.3 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 4.3
Waste heat revenue | ​ | ​ | 0.4 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.4
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 0.4 | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.4
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.5 | ​ | ​ | 0.5
Miscellaneous revenue | ​ | ​ | — | ​ | ​ | 1.0 | ​ | ​ | 1.6 | ​ | ​ | — | ​ | ​ | 2.6
​ | ​ |  | 40.6 | ​ |  | 57.7 | ​ |  | 36.2 | ​ |  | 0.5 | ​ |  | 135.0
​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Six Months Ended June 30, 2019
​ |  |  | ​ | ​ |  | ​ | ​ |  | ​ |  |  | ​ |  |  | Consolidated
​ | ​ | ​ | Solid Fuel | ​ | ​ | Natural Gas | ​ | ​ | Hydroelectric | ​ | ​ | Corporate | ​ | ​ | Total
Project revenue: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Energy sales | ​ | $ | 18.2 | ​ | $ | 15.9 | ​ | $ | 39.4 | ​ | $ | — | ​ | $ | 73.5
Energy capacity revenue | ​ |  | 20.0 | ​ |  | 41.8 | ​ |  | — | ​ |  | — | ​ |  | 61.8
Steam energy and capacity revenue | ​ | ​ | — | ​ | ​ | (0.1) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (0.1)
Ancillary and transmission services | ​ | ​ | — | ​ | ​ | 7.3 | ​ | ​ | 1.6 | ​ | ​ | — | ​ | ​ | 8.9
Asset management and operation | ​ | ​ | — | ​ | ​ | — | ​ | ​ | — | ​ | ​ | 0.5 | ​ | ​ | 0.5
Miscellaneous revenue | ​ | ​ | 0.1 | ​ | ​ | (0.4) | ​ | ​ | — | ​ | ​ | — | ​ | ​ | (0.3)
​ | ​ |  | 38.3 | ​ |  | 64.5 | ​ |  | 41.0 | ​ |  | 0.5 | ​ |  | 144.3
​ Contract balances ​ Contract liabilities as of June 30, 2020 include a $0.1 million fuel reserve fund at Dorchester (Solid Fuel segment), a $0.1 million steam sale credit at the San Diego plants (Natural Gas segment), and $0.4 million water license fee at Mamquam (Hydroelectric segment). Contract liabilities as of December 31, 2019 include a $0.2 million fuel reserve fund at Dorchester and a $0.1 million steam sale credit at the San Diego plants. We had no contract assets at June 30, 2020 and December 31, 2019. ​

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- Definition The entire disclosure of revenue from contract with customer to transfer good or service and to transfer nonfinancial asset. Includes, but is not limited to, disaggregation of revenue, credit loss recognized from contract with customer, judgment and change in judgment related to contract with customer, and asset recognized from cost incurred to obtain or fulfill contract with customer. Excludes insurance and lease contracts. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -URI http://asc.fasb.org/topic&trid=49130388 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130551-203045 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 13 -Subparagraph (b)(2) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130556-203045 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130550-203045 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12 -Subparagraph (e) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045 Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12 -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045 Reference 9: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130558-203045 Reference 10: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 12 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121604090&loc=SL49130554-203045 + Details
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