v2.4.0.6

Basic and diluted earnings (loss) per share (Tables) | 12 Months Ended
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Dec. 31, 2012
Basic and diluted earnings (loss) per share |
Schedule of diluted net income and potentially dilutive shares utilized in the per share calculation | The following table sets forth the diluted net income and potentially dilutive shares utilized in the per share calculation for the years ended December 31, 2012, 2011 and 2010:
|  | 2012 |  | 2011 |  | 2010 |
--- | --- | --- | --- | --- | --- | --- | ---
Numerator: |  |  |  |  |  |  |  |  |  |
Loss from continuing operations attributable to Atlantic Power Corporation |  | $ | (129,235 | ) | $ | (74,585 | ) | $ | (27,879 | )
Income from discontinued operations, net of tax |  |  | 16,459 |  |  | 36,177 |  |  | 24,127 |
Net loss attributable to Atlantic Power Corporation |  | $ | (112,776 | ) | $ | (38,408 | ) | $ | (3,752 | )
Denominator: |  |  |  |  |  |  |  |  |  |
Weighted average basic shares outstanding |  |  | 116,426 |  |  | 77,466 |  |  | 61,706 |
Dilutive potential shares: |  |  |  |  |  |  |  |  |  |
Convertible debentures |  |  | 17,353 |  |  | 13,962 |  |  | 12,339 |
LTIP notional units |  |  | 489 |  |  | 438 |  |  | 542 |
Potentially dilutive shares |  |  | 134,268 |  |  | 91,866 |  |  | 74,587 |
Diluted loss per share from continuing operations attributable to Atlantic Power Corporation |  | $ | (1.11 | ) | $ | (0.96 | ) | $ | (0.45 | )
Diluted earnings per share from discontinued operations |  |  | 0.14 |  |  | 0.46 |  |  | 0.39 |
Diluted loss per share attributable to Atlantic Power Corporation |  | $ | (0.97 | ) | $ | (0.50 | ) | $ | (0.06 | )

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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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