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Investment in ATC (Tables)

12 Months Ended

Dec. 31, 2012

Investment in ATC [Abstract]

ALLETE's Interest in ATC [Table Text Block]

ALLETE’s Interest in ATC
Year Ended December 31	2012			2011
Millions
Equity Investment Beginning Balance		$98.9			$93.3
Cash Investments	4.7			2.0
Equity in ATC Earnings	19.4			18.4
Distributed ATC Earnings	(15.7		)	(14.8		)
Equity Investment Ending Balance		$107.3			$98.9

ATC Summarized Financial Data [Table Text Block]

ATC Summarized Financial Data
Balance Sheet Data
As of December 31	2012			2011
Millions
Current Assets		$63.1			$58.7
Non-Current Assets	3,274.7			3,053.7
Total Assets		$3,337.8			$3,112.4
Current Liabilities		$251.5			$298.5
Long-Term Debt	1,550.0			1,400.0
Other Non-Current Liabilities	95.8			82.6
Members’ Equity	1,440.5			1,331.3
Total Liabilities and Members’ Equity		$3,337.8			$3,112.4

Income Statement Data
Year Ended December 31	2012			2011			2010
Millions
Revenue		$603.2			$567.2			$556.7
Operating Expense	281.0			261.6			251.1
Other Expense	84.8			81.7			85.9
Net Income		$237.4			$223.9			$219.7
ALLETE’s Equity in Net Income		$19.4			$18.4			$17.9

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- Definition

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

+ References

No definition available.

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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 FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

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



Reference 2: 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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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