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Acquisitions - Acquisition of Non-Controlling Interest (Details) $ in Millions | Apr. 15, 2016 USD ($)
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ALLETE Clean Energy [Member] |
Non-Controlling Interest [Line Items] |
Payment to Acquire Non-Controlling Interest | $ 8.0

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- Definition Decrease in noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests). + 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 810 -SubTopic 10 -Section 45 -Paragraph 23 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4569655-111683 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 45 -Paragraph 24 -URI http://asc.fasb.org/extlink&oid=51664549&loc=SL4616395-111683 + Details
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