v3.20.2

Basic and diluted earnings per share (Tables) | 9 Months Ended
--- | ---
Sep. 30, 2020
Basic and diluted earnings per share |
Schedule of diluted net income and potentially dilutive shares utilized in the per share calculation | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | Three Months Ended September 30, | ​ | Nine Months Ended September 30,
Basic |  | 2020 |  | 2019 |  | 2020 |  | 2019
Numerator: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Net income attributable to Atlantic Power Corporation | ​ | $ | 16.2 | ​ | $ | 12.6 | ​ | $ | 40.0 | ​ | $ | 22.7
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
Diluted |  | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
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
​ | ​ | ​ | 17.2 | ​ | ​ | 13.6 | ​ | ​ | 42.8 | ​ | ​ | 25.8
Denominator: | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
Weighted average basic shares outstanding | ​ |  | 89.5 | ​ |  | 109.4 | ​ |  | 98.1 | ​ |  | 109.4
Share-based compensation | ​ |  | 0.9 | ​ |  | 1.0 | ​ |  | 0.9 | ​ |  | 1.0
Convertible debentures | ​ |  | 27.4 | ​ |  | 27.4 | ​ |  | 27.4 | ​ |  | 27.9
​ | ​ |  | 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 Tabular disclosure of an entity's basic and diluted earnings per share calculations, including a reconciliation of numerators and denominators of the basic and diluted per-share computations for income from continuing operations. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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