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Acquisitions (Details) (USD $) In Millions, unless otherwise specified | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2014 | Jan. 30, 2014 | Dec. 31, 2013
Business Acquisition [Line Items] |  |  |
Business Acquisition, Effective Date of Acquisition | Jan. 30, 2014 |  |
Business Acquisition, Transaction Costs |  | $ 27.0 |
Escrow Deposit Disbursements Related to Property Acquisition |  |  | $ 5.4
Lake Benton [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Business Acquisition, Name of Acquired Entity | Lake Benton |  |
Generating Capacity (MW) |  | 104 |
Storm Lake [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Business Acquisition, Name of Acquired Entity | Storm Lake |  |
Generating Capacity (MW) |  | 77 |
Condon [Member] |  |  |
Business Acquisition [Line Items] |  |  |
Business Acquisition, Name of Acquired Entity | Condon |  |
Generating Capacity (MW) |  | 50 |

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- Definition Capacity of a generating facility, unit, or project in megawatts. + References No definition available. + Details
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- Definition Amount of direct costs of the business combination including legal, accounting, and other costs incurred to consummate the business acquisition. + References No definition available. + Details
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- Definition Date when the acquirer obtains control of the acquiree, in CCYY-MM-DD format. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e845-128460 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Acquisition Date -URI http://asc.fasb.org/extlink&oid=6919109 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 25 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=21917927&loc=d3e848-128460 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Details
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- Definition Name of the acquired entity. + 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 (a) -URI http://asc.fasb.org/extlink&oid=25497992&loc=d3e1392-128463 + Details
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- Definition The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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