Business Segments (Tables)

3 Months Ended

Mar. 31, 2016

Segment Reporting [Abstract]

Business Segments [Table Text Block]

	Three Months Ended
	March 31,
	2016			2015
Millions
Operating Revenue
Regulated Operations	$252.3			$262.8
Energy Infrastructure and Related Services
ALLETE Clean Energy	23.6			12.4
U.S. Water Services	32.4			15.5
Corporate and Other	25.5			29.3
Total Operating Revenue		$333.8			$320.0
Net Income (Loss) Attributable to ALLETE
Regulated Operations (a)		$42.4			$41.0
Energy Infrastructure and Related Services
ALLETE Clean Energy	6.1			2.5
U.S. Water Services	(0.5		)	(0.1		)
Corporate and Other (a)	(2.1		)	(3.5		)
Total Net Income Attributable to ALLETE		$45.9			$39.9

(a) In 2015, an intercompany loan agreement was entered into and interest expense was allocated to certain subsidiaries which is eliminated in consolidation. Prior period segment results have been revised to conform to the current presentation as if the intercompany loan existed as of January 1, 2015.

	March 31, 2016		December 31, 2015
Millions
Assets
Regulated Operations (a)	$3,822.3		$3,853.1
Energy Infrastructure and Related Services
ALLETE Clean Energy (a)	498.1		501.5
U.S. Water Services	256.6		258.3
Corporate and Other	295.7		281.6
Total Assets (a)		$4,872.7		$4,894.5

(a) As a result of revised accounting guidance adopted in the first quarter of 2016, we reclassified unamortized debt issuance costs from Other Non-Current Assets to Long-Term Debt on the Consolidated Balance Sheet. Prior period segment assets have been revised to conform to the current presentation. (See Note 1. Operations and Significant Accounting Policies.)