Segment and geographic information - Geographic (Details) - USD ($) $ in Millions |
3 Months Ended | ||
|---|---|---|---|
Mar. 31, 2020 |
Mar. 31, 2019 |
Dec. 31, 2019 |
|
| Revenue and Assets | |||
| Project revenues | $ 72.8 | $ 73.0 | |
| Property, Plant and Equipment, net of accumulated depreciation | 490.5 | $ 502.1 | |
| PPA'S and other intangible assets, net of accumulated amortization | 137.5 | 144.3 | |
| Assets | 882.0 | 1,027.0 | 935.6 |
| United States | |||
| Revenue and Assets | |||
| Project revenues | 48.2 | 52.1 | |
| Property, Plant and Equipment, net of accumulated depreciation | 357.1 | 353.9 | |
| PPA'S and other intangible assets, net of accumulated amortization | 136.3 | 142.8 | |
| Assets | 715.9 | 762.3 | |
| Canada | |||
| Revenue and Assets | |||
| Project revenues | 24.6 | $ 20.9 | |
| Property, Plant and Equipment, net of accumulated depreciation | 133.4 | 148.2 | |
| PPA'S and other intangible assets, net of accumulated amortization | 1.2 | 1.5 | |
| Assets | $ 166.1 | $ 173.3 | |