Basic and diluted earnings per share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2020 |
Sep. 30, 2019 |
Sep. 30, 2020 |
Sep. 30, 2019 |
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| Numerator: | ||||
| Net income attributable to Atlantic Power Corporation | $ 16.2 | $ 12.6 | $ 40.0 | $ 22.7 |
| Add: convertible debenture interest expense | 1.0 | 1.0 | 2.8 | 3.1 |
| Net income (loss) available to common stockholder, Diluted | $ 17.2 | $ 13.6 | $ 42.8 | $ 25.8 |
| Denominator: | ||||
| Weighted average basic shares outstanding | 89.5 | 109.4 | 98.1 | 109.4 |
| Basic earnings per share attributable to Atlantic Power Corporation | $ 0.18 | $ 0.12 | $ 0.41 | $ 0.21 |
| Share-based compensation (in shares) | 0.9 | 1.0 | 0.9 | 1.0 |
| Convertible debentures (in shares) | 27.4 | 27.4 | 27.4 | 27.9 |
| Weighted Average Number of Potentially Diluted Shares | 117.8 | 137.8 | 126.4 | 138.3 |
| Diluted earnings per share attributable to Atlantic Power Corporation | $ 0.15 | $ 0.10 | $ 0.34 | $ 0.19 |
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- Definition The weighted average number of potentially diluted shares that would be used to calculate EPS, including potentially dilutive shares. No definition available.
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- Definition The amount of net income (loss) from continuing operations 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) derived from continuing operations during 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/disclosureRef
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The after-tax amount of interest recognized in the period associated with any convertible debt. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References 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, after deduction of tax, noncontrolling interests, dividends on preferred stock and participating securities, and addition from assumption of issuance of common shares for dilutive potential common shares; of income (loss) available to common shareholders. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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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://www.xbrl.org/2003/role/disclosureRef
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