v2.4.0.8

Acquisitions and divestments (Details) (USD $) In Millions, except Share data, unless otherwise specified | 9 Months Ended | 0 Months Ended | 1 Months Ended |  |  | 0 Months Ended | 1 Months Ended |  | 1 Months Ended |  | 0 Months Ended | 3 Months Ended | 9 Months Ended | 0 Months Ended | 3 Months Ended
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Sep. 30, 2012 | May 02, 2013 Canadian Hills | Jul. 31, 2012 Canadian Hills | Mar. 30, 2012 Canadian Hills | Dec. 31, 2012 Canadian Hills item | Sep. 30, 2013 Canadian Hills | Jan. 31, 2012 Canadian Hills MW | Apr. 12, 2013 Auburndale, Lake and Pasco | Jan. 30, 2013 Auburndale, Lake and Pasco | Apr. 30, 2013 Auburndale, Lake and Pasco | Apr. 30, 2013 Path 15 | Sep. 30, 2013 Path 15 | May 31, 2012 Primary Energy Recycling Corporation | Feb. 29, 2012 Primary Energy Recycling Corporation | Feb. 16, 2012 Primary Energy Recycling Corporation | Apr. 02, 2013 Gregory | Sep. 30, 2013 Gregory | Sep. 30, 2013 Gregory | Sep. 04, 2012 Badger Creek | Jun. 30, 2012 Badger Creek
Acquisition and divestments |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage acquired in entity |  |  |  | 48.00% |  |  | 51.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Wind power project capacity (in MW) |  |  |  |  |  |  | 300 |  |  |  |  |  |  |  |  |  |  |  |  |
Percentage of ownership interest |  |  |  | 99.00% |  |  |  |  |  |  |  |  |  |  | 14.30% |  |  |  | 50.00% |
Percentage of retained interest |  |  |  | 1.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Project-level construction financing facility |  |  |  | $ 310.0 |  |  |  |  |  |  |  | $ 137.2 |  |  |  |  |  |  |  |
Construction loan |  |  |  | 290.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Letter of credit facility |  |  |  | 20.0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Letter of credit facility, term |  |  |  | 5 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Investment in equity |  |  | 190 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tax equity investments received |  |  |  |  | 225 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of institutional tax equity investors by whom tax equity investments received |  |  |  |  | 4 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Own tax equity investment |  | 44 |  |  | 44 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Interest sold (as a percent) |  | 100.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Tax equity interests |  | 269 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Short-term debt |  |  |  |  | 265 | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of remaining tax equity ownership |  | 42.1 |  |  |  |  |  | 92.0 |  | 25.0 |  |  |  |  |  |  |  |  |  |
Total price |  |  |  |  |  |  |  |  | 140.0 |  | 56.0 |  |  | 30.2 |  | 274.2 |  |  |  |
Expected proceeds from sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 34.6 |  |  |  |
Proceeds from sale to be held in escrow account |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 |  |  |  |
Term Of Escrow Account |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 year |  |  |  |
Net cash proceeds from sale | 27.9 |  |  |  |  |  |  | 117.0 |  |  | 52.0 |  |  |  |  |  |  |  | 3.7 |
Management termination fee |  |  |  |  |  |  |  |  |  |  | 4.0 |  |  | 6.0 |  |  |  |  |  |
Outstanding balance of senior credit facility |  |  |  |  |  |  |  | 64.1 |  |  |  |  |  |  |  |  |  |  |  |
Impairment charge on pending sale |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 3.0
Price of entity's common membership interest in equity method investee |  |  |  |  |  |  |  |  |  |  |  |  |  | 24.2 |  |  |  |  |  |
Gain on sale of equity method investment |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.6 |  |  |  | $ 30.4 | $ 30.4 |  |
Entity's common membership interest to be purchased in equity method investee (in shares) |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,462,830 |  |  |  |  |  |

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- Definition Represents the amount of sales proceeds received on disposal of the common membership interest in an equity method investment. + References No definition available. + Details
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- Definition Represents the number of shares to be purchased on disposal of the common membership interest in an equity method investment. + References No definition available. + Details
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- Definition Represents the amount of management termination fee received on disposal of an equity method investment. + References No definition available. + Details
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- Definition Represents the percentage of investment sold, accounted under the equity method of accounting. + References No definition available. + Details
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- Definition Represents the expected cash inflow associated with the sale of equity method investments. + References No definition available. + Details
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- Definition Represents the number of institutional tax equity investors by whom tax equity investments were received. + References No definition available. + Details
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- Definition The expected cash inflow associated with the sale of equity method investments to be held in escrow account for specified period of time. + References No definition available. + Details
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- Definition Represents the amount of tax equity investment including entity's owned tax investment. + References No definition available. + Details
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- Definition Represents the amount of tax equity investments received during the period. + References No definition available. + Details
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- Definition Percentage of voting equity interests acquired at the acquisition date in the business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition This element represents the carrying value of a short-term real estate loan to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project, usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. Note that there are separate concepts for the current and noncurrent portions of long-term construction loans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)(1)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 20 -Article 5 + Details
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- Definition This item represents the amount of net sales proceeds received on disposal of an equity method investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 35 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32847-111569 + Details
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- Definition This item represents an other than temporary decline in value that has been recognized against an investment accounted for under the equity method of accounting. The excess of the carrying amount over the fair value of the investment represents the amount of the write down which is or was reflected in earnings. The written down value is a new cost basis with the adjusted value of the investment becoming its new carrying value subject to the equity accounting method. Evidence of a loss in value might include, but would not necessarily be limited to, absence of an ability to recover the carrying amount of the investment or inability of the investee to sustain an earnings capacity which would justify the carrying amount of the investment. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 35 -Paragraph 32 -URI http://asc.fasb.org/extlink&oid=7658923&loc=d3e32787-111569 + Details
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- Definition The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 323 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571 + Details
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- Definition Amount of gain (loss) on sale or disposal of an equity method investment. + References No definition available. + Details
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- Definition The total amount of the contingent obligation under letters of credit outstanding as of the reporting date. + References No definition available. + Details
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- Definition Amount borrowed under the credit facility as of the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19, 22 -Article 5 + Details
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- Definition This element represents the current and noncurrent portions of a long-term real estate loan with an initial maturity beyond one year or beyond the normal operating cycle, if longer, to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project (generally one to seven years), usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 20 -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Article 5 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 22 -Article 5 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.16) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19,20,22) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition The cash inflow associated with the sale of equity method investments, which are investments in joint ventures and entities in which the entity has an equity ownership interest normally of 20 to 50 percent and exercises significant influence. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Investing Activities -URI http://asc.fasb.org/extlink&oid=6516133 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 12 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3179-108585 + Details
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- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 19 -Subparagraph a -Article 5 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.19(a)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.13) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03.(a),16(a)(1)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 16 -Subparagraph a(1) -Article 7 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 13 -Subparagraph 2, 3 -Article 9 + Details
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