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Investment in ATC (Tables)

9 Months Ended

Sep. 30, 2011

Equity Method Investments and Joint Ventures [Abstract]

ALLETE's Investment in ATC [Table Text Block]

ALLETE’s Investment in ATC
Millions
Equity Investment Balance as of December 31, 2010	$93.3
Cash Investments	2.0
Equity in ATC Earnings	13.7
Distributed ATC Earnings	(11.1)
Equity Investment Balance as of September 30, 2011	$97.9

ATC Summarized Financial Data [Table Text Block]

	Quarter Ended				Nine Months Ended
ATC Summarized Financial Data	September 30,				September 30,
Income Statement Data	2011		2010		2011		2010
Millions
Revenue	$142.8		$136.9		$420.6		$414.1
Operating Expense	66.4		60.2		192.5		185.9
Other Expense	19.7		21.7		61.6		64.0
Net Income	$56.7		$55.0		$166.5		$164.2
ALLETE’s Equity in Net Income	$4.7		$4.5		$13.7		$13.4

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- Definition

Tabular disclosure of summarized financial data reported by an equity method investment of the entity.

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- Definition

Tabular disclosure of equity method investments in common stock. The disclosure may include: (a) the name of each investee or group of investments for which combined disclosure is appropriate, (2) the percentage ownership of common stock, (3) the difference, if any, between the carrying amount of an investment and the value of the underlying equity in the net assets and the accounting treatment of difference, if any, and (4) the aggregate value of each identified investment based on its quoted market price, if available.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher AICPA

-Name Accounting Principles Board Opinion (APB)

-Number 18

-Paragraph 20

-Subparagraph a, b

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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