Segment and geographic information - Geographic (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | |||
|---|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2020 |
Sep. 30, 2019 |
Dec. 31, 2019 |
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| Revenue and Assets | |||||
| Project revenues | $ 65.2 | $ 71.1 | $ 200.3 | $ 215.4 | |
| Property, Plant and Equipment, net of accumulated depreciation | 494.8 | 494.8 | $ 502.1 | ||
| PPA'S and other intangible assets, net of accumulated amortization | 125.8 | 125.8 | 144.3 | ||
| Assets | 840.4 | 997.2 | 840.4 | 997.2 | 935.6 |
| United States | |||||
| Revenue and Assets | |||||
| Project revenues | 46.5 | 54.9 | 140.1 | 159.5 | |
| Property, Plant and Equipment, net of accumulated depreciation | 357.7 | 357.7 | 353.9 | ||
| PPA'S and other intangible assets, net of accumulated amortization | 124.8 | 124.8 | 142.8 | ||
| Assets | 666.5 | 666.5 | 762.3 | ||
| Canada | |||||
| Revenue and Assets | |||||
| Project revenues | 18.7 | $ 16.2 | 60.2 | $ 55.9 | |
| Property, Plant and Equipment, net of accumulated depreciation | 137.1 | 137.1 | 148.2 | ||
| PPA'S and other intangible assets, net of accumulated amortization | 1.0 | 1.0 | 1.5 | ||
| Assets | $ 173.9 | $ 173.9 | $ 173.3 | ||
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- Definition Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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