Operations and Significant Accounting Policies (Tables)

3 Months Ended

Mar. 31, 2015

Operations and Significant Accounting Policies [Abstract]

Inventories [Table Text Block]

Inventories	March 31, 2015			December 31, 2014
Millions
Regulated Operations Inventories
Fuel		$38.0			$29.0
Materials and Supplies	34.6			35.2
Total Regulated Operations Inventories	72.6			64.2
Investments and Other Inventories (a)
Materials and Supplies	16.3			16.3
Raw Materials	3.1			—
Work in Progress	1.0			—
Finished Goods	10.2			—
Reserve for Obsolescence	(0.5		)	—
Total Investments and Other Inventories	30.1			16.3
Total Inventories		$102.7			$80.5

(a) Raw materials, Work in Progress, Finished Goods, and Reserve for Obsolescence presented are attributable to U.S. Water Services which was acquired February 10, 2015.

Prepayments and Other Current Assets [Table Text Block]

Prepayments and Other Current Assets	March 31, 2015		December 31, 2014
Millions
Deferred Fuel Adjustment Clause		$15.6		$16.3
Construction Costs for Development Project (a)	48.4		48.2
Restricted Cash (b)	5.6		2.7
Other	18.9		14.8
Total Prepayments and Other Current Assets		$88.5		$82.0

(a) Construction Costs for Development Project relate to ALLETE Clean Energy’s acquisition in November 2014 of a project to develop and construct a wind energy facility in 2015. (See Other Current Liabilities table and Note 4. Acquisitions.)

(b) Restricted Cash related to ALLETE Clean Energy’s wind energy facilities operating expense and capital distribution reserve requirements and cash pledged as collateral by U.S. Water Services for stand-by letters of credit.

Other Current and Non-Current Liabilities [Table Text Block]

Other Current Liabilities	March 31, 2015		December 31, 2014
Millions
Customer Deposits		$20.0		$19.7
Power Purchase Agreements (a)	18.9		19.4
Construction Deposits Received for Development Project (b)	54.3		54.3
Other	25.4		27.4
Total Other Current Liabilities		$118.6		$120.8

(a) Power Purchase Agreements were acquired in conjunction with the ALLETE Clean Energy wind energy facilities acquisitions in 2014. (See Note 4. Acquisitions.)

(b) Construction Deposits Received for Development Project relate to ALLETE Clean Energy’s project to develop and construct a wind energy facility in 2015. (See Prepayments and Other Current Assets table and Note 4. Acquisitions.)

Other Non-Current Liabilities	March 31, 2015		December 31, 2014
Millions
Asset Retirement Obligation		$111.6		$109.2
Power Purchase Agreements (a)	106.3		110.7
Contingent Consideration (b)	35.8		—
Other	48.6		45.1
Total Other Non-Current Liabilities		$302.3		$265.0

(a) Power Purchase Agreements were acquired in conjunction with the ALLETE Clean Energy wind energy facilities acquisitions in 2014. (See Note 4. Acquisitions.)

(b) Contingent Consideration relates to the estimated fair value of the earnings-based payment to acquire the remaining ownership interest in U.S. Water Services. (See Note 4. Acquisitions and Note 7. Fair Value.)

Supplemental Statement of Cash Flows Information [Table Text Block]

Supplemental Statement of Cash Flows Information.

Three Months Ended March 31,	2015		2014
Millions
Cash Paid During the Period for Interest – Net of Amounts Capitalized		$15.3		$12.4
Cash Paid During the Period for Income Taxes		$0.1		$0.2
Noncash Investing and Financing Activities
Decrease in Accounts Payable for Capital Additions to Property, Plant and Equipment	$(32.2)		$(22.6)
Capitalized Asset Retirement Costs	$1.2			$0.6
AFUDC–Equity		$0.9		$1.8
ALLETE Common Stock Contributed to the Pension Plan	—			$19.5
Contingent Consideration		$35.7	—