Business Segments (Tables)

12 Months Ended

Dec. 31, 2015

Segment Reporting [Abstract]

Business Segments [Table Text Block]

As of December 31	2015		2014
Millions
Assets
Regulated Operations	$3,862.6		$3,709.6
Energy Infrastructure and Related Services
ALLETE Clean Energy	504.6		291.9
U.S. Water Services	258.3		—
Corporate and Other	281.6		359.3
Total Assets		$4,907.1		$4,360.8
Capital Expenditures
Regulated Operations	$224.4		$583.5
Energy Infrastructure and Related Services
ALLETE Clean Energy	8.6		4.2
U.S. Water Services	2.9		—
Corporate and Other	15.9		16.6
Total Capital Expenditures		$251.8		$604.3

Year Ended December 31	2015			2014			2013
Millions
Operating Revenue
Regulated Operations		$991.2			$1,003.5			$925.5
Energy Infrastructure and Related Services
ALLETE Clean Energy	262.1			33.2			—
U.S. Water Services	119.8			—			—
Corporate and Other	113.3			100.1			92.9
Total Operating Revenue		$1,486.4			$1,136.8			$1,018.4
Net Income (Loss) Attributable to ALLETE
Regulated Operations (a)		$131.6			$123.0			$103.6
Energy Infrastructure and Related Services
ALLETE Clean Energy	29.9			3.3			(3.4		)
U.S. Water Services	0.9			—			—
Corporate and Other (a)	(21.3		)	(1.5		)	4.5
Total Net Income Attributable to ALLETE		$141.1			$124.8			$104.7
Depreciation and Amortization
Regulated Operations		$135.1			$118.0			$110.2
Energy Infrastructure and Related Services
ALLETE Clean Energy	18.7			10.1			—
U.S. Water Services	7.3			—			—
Corporate and Other	8.9			7.6			6.4
Total Depreciation and Amortization		$170.0			$135.7			$116.6
Impairment of Real Estate
Corporate and Other	$36.3			—			—
Interest Expense
Regulated Operations (a)	$53.9			$49.2			$44.4
Energy Infrastructure and Related Services
ALLETE Clean Energy	3.3			0.8			—
U.S. Water Services	1.4			—			—
Corporate and Other (a)	8.6			7.1			8.2
Eliminations (a)	(2.3		)	(2.3		)	(2.3		)
Total Interest Expense	$64.9			$54.8			$50.3
Equity Earnings in ATC
Regulated Operations	$16.3			$19.6			$20.3
Income Tax Expense (Benefit)
Regulated Operations		$24.4			$39.0			$35.1
Energy Infrastructure and Related Services
ALLETE Clean Energy	21.0			2.3			(2.3		)
U.S. Water Services	0.9			—			—
Corporate and Other	(21.0		)	(4.6		)	(4.1		)
Total Income Tax Expense		$25.3			$36.7			$28.7

(a) During 2015, an intercompany loan agreement was entered into and interest expense was allocated to certain subsidiaries. The amounts are 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, 2013.