v3.4.0.3

Stockholders Equity | 3 Months Ended
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Mar. 31, 2016
Equity |
Stockholders' Equity Note Disclosure [Text Block] | 12. Equity The following table provides a reconciliation of the beginning and ending equity attributable to shareholders of Atlantic Power Corporation, preferred shares issued by a subsidiary company, noncontrolling interests and total equity for the three months ended March 31, 2016 and 2015:
|  | Three months ended March 31, 2016 |
|  | Total Atlantic |  | Preferred shares |  |  |  |
|  | Power Corporation |  | issued by a subsidiary |  |  |  |
|  | Shareholders’ Equity |  | company |  | Total Equity |
Balance at January 1 |  | $ | 213.9 |  | $ | 221.3 |  | $ | 435.2 |
Net income (loss) |  |  | (14.9) |  |  | 2.0 |  |  | (12.9) |
Realized and unrealized loss on hedging activities, net of tax |  |  | (0.3) |  |  | — |  |  | (0.3) |
Foreign currency translation adjustment |  |  | 18.5 |  |  | — |  |  | 18.5 |
Common share repurchases |  |  | (0.9) |  |  | — |  |  | (0.9) |
Stock-based compensation |  |  | 0.6 |  |  | — |  |  | 0.6 |
Dividends declared on preferred shares of a subsidiary company |  |  | — |  |  | (2.0) |  |  | (2.0) |
Balance at March 31 |  | $ | 216.9 |  | $ | 221.3 |  | $ | 438.2 |
|  | Three months ended March 31, 2015 |
|  | Total Atlantic |  | Preferred shares |  |  |  |  |  |  |
|  | Power Corporation |  | issued by a subsidiary |  | Noncontrolling |  |  |  |
|  | Shareholders’ Equity |  | company |  | Interests |  | Total Equity |
Balance at January 1 |  | $ | 356.2 |  | $ | 221.3 |  | $ | 239.0 |  | $ | 816.5 |
Net income (loss) |  |  | 17.5 |  |  | 2.3 |  |  | (7.5) |  |  | 12.3 |
Realized and unrealized gain on hedging activities, net of tax |  |  | (0.3) |  |  | — |  |  | — |  |  | (0.3) |
Foreign currency translation adjustment |  |  | (35.1) |  |  | — |  |  | — |  |  | (35.1) |
Stock-based compensation |  |  | 0.4 |  |  | — |  |  | — |  |  | 0.4 |
Dividends paid to noncontrolling interest |  |  | — |  |  | — |  |  | (2.7) |  |  | (2.7) |
Dividends declared on common shares |  |  | (2.9) |  |  | — |  |  | — |  |  | (2.9) |
Dividends declared on preferred shares of a subsidiary company |  |  | — |  |  | (2.3) |  |  | — |  |  | (2.3) |
Balance at March 31 |  | $ | 335.8 |  | $ | 221.3 |  | $ | 228.8 |  | $ | 785.9 |

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- Definition The entire disclosure for shareholders' equity comprised of portions attributable to the parent entity and noncontrolling interest, including other comprehensive income. Includes, but is not limited to, balances of common stock, preferred stock, additional paid-in capital, other capital and retained earnings, accumulated balance for each classification of other comprehensive income and amount of comprehensive income. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08.(d),(e)) -URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21484-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB TOPIC 4.E) -URI http://asc.fasb.org/extlink&oid=27010918&loc=d3e74512-122707 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21488-112644 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29-31) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 4 -Subparagraph (SAB TOPIC 4.C) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187143-122770 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21506-112644 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 9: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 30 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6405834&loc=d3e23285-112656 Reference 10: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21475-112644 Reference 11: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Preferred Stock -URI http://asc.fasb.org/extlink&oid=6521494 Reference 12: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 13: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21564-112644 Reference 14: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section E Reference 15: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Staff Accounting Bulletin (SAB) -Number Topic 4 -Section C + Details
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