v2.4.0.8

Basic and diluted earnings (loss) per share | 9 Months Ended
--- | ---
Sep. 30, 2013
Basic and diluted earnings (loss) per share |
Basic and diluted earnings (loss) per share | 10. Basic and diluted earnings (loss) per share Basic earnings (loss) per share are calculated by dividing net income (loss) by the weighted average common shares outstanding during their respective period. Diluted earnings (loss) per share are computed including dilutive potential shares as if they were outstanding shares during the year. Dilutive potential shares include shares that would be issued if all of the convertible debentures were converted into shares at January 1, 2013. Dilutive potential shares also include the weighted average number of shares, as of the date such notional units were granted, that would be issued if the unvested notional units outstanding under the LTIP were vested and redeemed for shares under the terms of the LTIP. The following table sets forth the diluted net income and potentially dilutive shares utilized in the per share calculation for the three and nine months ended September 30, 2013 and 2012:
|  | Three months ended September 30, |  | Nine months ended September 30, |
--- | --- | --- | --- | --- | ---
|  | 2013 |  | 2012 |  | 2013 |  | 2012 |
Numerator: |  |  |  |  |  |  |  |  |  |  |  |  |
Loss from continuing operations attributable to Atlantic Power Corporation |  | $ | (40.9 | ) | $ | (26.5 | ) | $ | (31.8 | ) | $ | (103.7 | )
Income (loss) from discontinued operations, net of tax |  |  | (0.4 | ) |  | 19.0 |  |  | (6.1 | ) |  | 48.8 |
Net loss attributable to Atlantic Power Corporation |  | $ | (41.3 | ) | $ | (7.5 | ) | $ | (37.9 | ) | $ | (54.9 | )
Denominator: |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average basic shares outstanding |  |  | 120.0 |  |  | 119.0 |  |  | 119.8 |  |  | 115.4 |
Dilutive potential shares: |  |  |  |  |  |  |  |  |  |  |  |  |
Convertible debentures |  |  | 27.7 |  |  | 20.5 |  |  | 27.7 |  |  | 15.7 |
LTIP notional units |  |  | 0.8 |  |  | 0.5 |  |  | 0.7 |  |  | 0.5 |
Potentially dilutive shares |  |  | 148.5 |  |  | 140.0 |  |  | 148.2 |  |  | 131.6 |
Diluted loss per share from continuing operations attributable to Atlantic Power Corporation |  | $ | (0.34 | ) | $ | (0.22 | ) | $ | (0.27 | ) | $ | (0.90 | )
Diluted earnings (loss) per share from discontinued operations |  |  | (0.00 | ) |  | 0.16 |  |  | (0.05 | ) |  | 0.42 |
Diluted loss per share attributable to Atlantic Power Corporation |  | $ | (0.34 | ) | $ | (0.06 | ) | $ | (0.32 | ) | $ | (0.48 | )
Potentially dilutive shares from convertible debentures and LTIP notional units have been excluded from fully diluted shares for the three and nine months ended September 30, 2013 and 2012 because their impact would be anti-dilutive.

X
- Details
Name: | us-gaap_EarningsPerShareAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for earnings per share. + 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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1278-109256 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7655603&loc=d3e1252-109256 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 55 -Paragraph 52 -URI http://asc.fasb.org/extlink&oid=32703322&loc=d3e4984-109258 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.21) -URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688 + Details
Name: | us-gaap_EarningsPerShareTextBlock
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration