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Acquisitions - Storm Lake I (Details) $ in Millions | 1 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Dec. 31, 2014 USD ($) MW | Dec. 31, 2014 USD ($) MW | Dec. 31, 2015 USD ($)
Liabilities Assumed [Abstract] |  |  |  |
Power Purchase Agreements - Non-Current Liability | [1] | $ 110.7 | $ 110.7 | $ 138.1
Restricted Cash - Non-Current |  | 5.3 | 5.3 | 8.1
Power Purchase Agreements - Current Liability | [2] | $ 19.4 | $ 19.4 | $ 23.3
Storm Lake I [Member] |  |  |  |
Business Acquisition [Line Items] |  |  |  |
Date of Acquisition |  | December 2014 |  |
Name of Acquired Entity |  | Storm Lake I |  |
Payments to Acquire Business |  | $ 15.1 |  |
Generating Capacity (MW) | MW |  | 108 | 108 |
Assets Acquired [Abstract] |  |  |  |
Cash and Cash Equivalents |  | $ 0.4 | $ 0.4 |
Other Current Assets |  | 4.7 | 4.7 |
Property, Plant and Equipment |  | 47.3 | 47.3 |
Other Non-Current Assets | [3] | 11.4 | 11.4 |
Total Assets Acquired |  | 63.8 | 63.8 |
Liabilities Assumed [Abstract] |  |  |  |
Current Liabilities | [4] | 8.2 | 8.2 |
Power Purchase Agreements - Non-Current Liability |  | 23.5 | 23.5 |
Non-Current Liabilities |  | 17.0 | 17.0 |
Total Liabilities Assumed |  | 48.7 | 48.7 |
Net Identifiable Assets Acquired |  | 15.1 | 15.1 |
Restricted Cash - Non-Current |  | $ 0.4 | 0.4 |
Goodwill |  | immaterial |  |
Deductible Goodwill |  | $ 0.0 | 0.0 |
Power Purchase Agreements - Current Liability |  | $ 7.5 | $ 7.5 |
Acquisition-Related Costs |  |  | immaterial |
[1] | Power Purchase Agreements acquired in conjunction with the ALLETE Clean Energy wind energy facilities acquisitions. (See Note 7. Acquisitions.)
[2] | Power Purchase Agreements acquired in conjunction with the ALLETE Clean Energy wind energy facilities acquisitions. (See Note 7. Acquisitions.)
[3] | Included in Other Non-Current Assets was $0.4 million of restricted cash and an immaterial amount of goodwill. For tax purposes, the purchase price allocation resulted in no allocation to goodwill.
[4] | Current Liabilities included $7.5 million related to the current portion of Power Purchase Agreements.

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