Unaudited selected quarterly financial data - (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
3 Months Ended | 12 Months Ended | |||||||||
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Dec. 31, 2019 |
Sep. 30, 2019 |
Jun. 30, 2019 |
Mar. 31, 2019 |
Dec. 31, 2018 |
Sep. 30, 2018 |
Jun. 30, 2018 |
Mar. 31, 2018 |
Dec. 31, 2019 |
Dec. 31, 2018 |
Dec. 31, 2017 |
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| Unaudited selected quarterly financial data | |||||||||||
| Project Revenue | $ 66.2 | $ 71.1 | $ 71.3 | $ 73.0 | $ 70.7 | $ 65.4 | $ 66.2 | $ 80.0 | $ 281.6 | $ 282.3 | $ 431.0 |
| Project (loss) income | (33.4) | 27.9 | 21.7 | 30.6 | 20.1 | 26.2 | 13.6 | 28.3 | 46.8 | 88.2 | (47.4) |
| Net (loss) income | (63.4) | 14.3 | 2.9 | 2.4 | 26.7 | (4.7) | 1.0 | 14.2 | (43.8) | 37.2 | |
| Net (loss) income attributable to Atlantic Power Corporation | $ (65.3) | $ 12.6 | $ 1.2 | $ 8.9 | $ 24.7 | $ (3.2) | $ (0.6) | $ 15.9 | $ (42.6) | $ 36.8 | $ (98.6) |
| (Loss) income per share attributable to Atlantic Power Corporation | $ (0.60) | $ 0.12 | $ 0.01 | $ 0.08 | $ 0.23 | $ (0.03) | $ (0.01) | $ 0.14 | $ (0.39) | $ 0.33 | $ (0.86) |
| Weighted average number of common shares outstanding - basic | 109.3 | 109.4 | 109.7 | 108.9 | 109.6 | 111.1 | 112.4 | 114.8 | 109.3 | 112.0 | 115.1 |
| Diluted earnings (loss) per share attributable to Atlantic Power Corporation | $ (0.60) | $ 0.10 | $ 0.01 | $ 0.07 | $ 0.18 | $ (0.03) | $ (0.01) | $ 0.12 | $ (0.39) | $ 0.29 | $ (0.86) |
| Weighted average number of common shares outstanding-diluted | 109.3 | 137.8 | 110.2 | 138.6 | 140.7 | 111.1 | 112.4 | 140.6 | 109.3 | 141.8 | 115.1 |
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- Definition The net result for the period of deducting project expenses from project revenues. No definition available.
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- Definition The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition Amount of income (loss) from continuing operations, nonoperating income (expense) and income (loss) from equity method investments, before deduction of income tax expense (benefit) and income (loss) attributable to noncontrolling interest, and addition of interest income (expense). No definition available.
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- Definition Amount, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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- References No definition available.
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- Definition The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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