v3.5.0.2

Equity (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 7 Months Ended
--- | --- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016
Increase (decrease) in shareholders' equity |  |  |  |  |
Balance at the beginning of the period |  |  | $ 435.2 | $ 816.5 |
Net (loss) income |  |  | (29.3) | 25.8 |
Realized and unrealized gain on hedging activities, net of tax |  | $ 0.3 | (0.3) |  |
Foreign currency translation adjustments | $ 1.0 | 4.5 | 19.4 | (30.6) |
Common share repurchases |  |  | (4.7) |  |
Stock-based compensation |  |  | 0.8 | 1.0 |
Dividends paid to noncontrolling interests |  |  |  | (3.7) |
Dividends declared on common shares |  |  |  | (5.8) |
Dividends declared on preferred shares of a subsidiary company |  |  | (4.2) | (4.6) |
Derecognition of noncontrolling interests upon sale of subsidiaries |  |  |  | (224.3) |
Balance at the end of the period | 416.9 | 574.3 | 416.9 | 574.3 | $ 416.9
Stock Repurchase Program |  |  |  |  |
Total Number of Shares Purchased |  |  |  |  | 2,025,080
Common stock repurchased, value |  |  |  |  | $ 4.7
Total Atlantic Power Corporation Shareholder's Equity |  |  |  |  |
Increase (decrease) in shareholders' equity |  |  |  |  |
Balance at the beginning of the period |  |  | 213.9 | 356.2 |
Net (loss) income |  |  | (33.5) | 32.2 |
Realized and unrealized gain on hedging activities, net of tax |  |  | (0.3) |  |
Foreign currency translation adjustments |  |  | 19.4 | (30.6) |
Common share repurchases |  |  | (4.7) |  |
Stock-based compensation |  |  | 0.8 | 1.0 |
Dividends declared on common shares |  |  |  | (5.8) |
Balance at the end of the period | 195.6 | 353.0 | 195.6 | 353.0 | 195.6
Preferred Shares of A Subsidiary Company |  |  |  |  |
Increase (decrease) in shareholders' equity |  |  |  |  |
Balance at the beginning of the period |  |  | 221.3 | 221.3 |
Net (loss) income |  |  | 4.2 | 4.6 |
Dividends declared on preferred shares of a subsidiary company |  |  | (4.2) | (4.6) |
Balance at the end of the period | $ 221.3 | $ 221.3 | $ 221.3 | 221.3 | $ 221.3
Noncontrolling Interests |  |  |  |  |
Increase (decrease) in shareholders' equity |  |  |  |  |
Balance at the beginning of the period |  |  |  | 239.0 |
Net (loss) income |  |  |  | (11.0) |
Dividends paid to noncontrolling interests |  |  |  | (3.7) |
Derecognition of noncontrolling interests upon sale of subsidiaries |  |  |  | $ (224.3) |

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- Definition Amount of paid and unpaid common stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK). + References Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 + Details
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- Definition Amount of paid and unpaid preferred stock dividends declared with the form of settlement in cash, stock and payment-in-kind (PIK). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 405 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6957935&loc=d3e64057-112817 Reference 2: 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 + Details
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- Definition Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders. + References Reference 1: 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 + Details
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- Definition The amount of the reduction or elimination during the period of a noncontrolling interest resulting from the parent's loss of control and deconsolidation of the entity in which one or more outside parties had a noncontrolling interest. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=18733093&loc=SL4573702-111684 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 + Details
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- Definition Amount after tax, before reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 20 -URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32211-110900 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (a-c) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6450520&loc=d3e32583-110901 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32022-110900 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 830 -SubTopic 30 -Section 45 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=6915805&loc=d3e32157-110900 + Details
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- Definition Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580 + Details
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- Definition The cash outflow to reacquire common stock during the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 15 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3291-108585 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Financing Activities -URI http://asc.fasb.org/extlink&oid=6513228 + Details
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- Definition The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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- Definition Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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- Definition Equity impact of the value of stock that has been repurchased during the period and has not been retired and is not held in treasury. Some state laws may mandate the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock. + References Reference 1: 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 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30, 31 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 + Details
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- Definition Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 55 -Paragraph 4I -URI http://asc.fasb.org/extlink&oid=35736750&loc=SL4590271-111686 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 16 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4568740-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4568447-111683 + Details
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