v2.4.0.6

Basic and diluted earnings (loss) per share (Tables) | 3 Months Ended
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Mar. 31, 2013
Basic and diluted earnings (loss) per share |
Schedule of diluted net income and potentially dilutive shares utilized in the per share calculation |
|  | Three months ended March 31, |
--- | --- | --- | ---
|  | 2013 |  | 2012 |
Numerator: |  |  |  |  |  |  |
Income (loss) from continuing operations attributable to Atlantic Power Corporation |  | $ | 5.6 |  | $ | (53.9 | )
Income from discontinued operations, net of tax |  |  | 0.9 |  |  | 11.6 |
Net loss attributable to Atlantic Power Corporation |  | $ | 6.5 |  | $ | (42.3 | )
Denominator: |  |  |  |  |  |  |
Weighted average basic shares outstanding |  |  | 119.5 |  |  | 113.6 |
Dilutive potential shares: |  |  |  |  |  |  |
Convertible debentures |  |  | 27.7 |  |  | 13.3 |
LTIP notional units |  |  | 0.4 |  |  | 0.5 |
Potentially dilutive shares |  |  | 147.6 |  |  | 127.4 |
Diluted loss per share from continuing operations attributable to Atlantic Power Corporation |  | $ | 0.04 |  | $ | (0.47 | )
Diluted earnings per share from discontinued operations |  |  | 0.01 |  |  | 0.10 |
Diluted loss per share attributable to Atlantic Power Corporation |  | $ | 0.05 |  | $ | (0.37 | )

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- Definition Tabular disclosure of the numerators and the denominators of the basic and diluted per-share (or per-unit) computations for income from continuing operations, including the effect that has been given to preferred dividends. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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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