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Earnings Per Share and Common Stock (Tables)

9 Months Ended

Sep. 30, 2012

Earnings Per Share and Common Stock [Abstract]

Reconciliation of Basic and Diluted Earnings Per Share [Table Text Block]

					2012											2011
Reconciliation of Basic and Diluted					Dilutive											Dilutive
Earnings Per Share	Basic				Securities			Diluted				Basic				Securities			Diluted
Millions Except Per Share Amounts
For the Quarter Ended September 30,
Net Income Attributable to ALLETE		$29.4							$29.4				$20.5							$20.5
Average Common Shares	37.7				0.1			37.8				35.6				0.1			35.7
Earnings Per Share		$0.78							$0.78				$0.57							$0.57
For the Nine Months Ended September 30,
Net Income Attributable to ALLETE		$68.2							$68.2				$74.7							$74.7
Average Common Shares	37.3				—			37.3				35.1				0.1			35.2
Earnings Per Share		$1.83							$1.83				$2.13							$2.12

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- Definition

Tabular disclosure of the reconciliation of basic net earnings per share (or unit) to diluted earnings per share (or unit).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257

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