Operations and Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2015

Operations and Significant Accounting Policies [Abstract]

Inventories [Table Text Block]

Inventories	September 30, 2015			December 31, 2014
Millions
Fuel		$54.0			$29.0
Materials and Supplies	52.6			51.5
Raw Materials	3.1			—
Work in Progress	0.7			—
Finished Goods	8.9			—
Reserve for Obsolescence	(0.2		)	—
Total Inventories		$119.1			$80.5

Prepayments and Other Current Assets [Table Text Block]

Prepayments and Other Current Assets	September 30, 2015		December 31, 2014
Millions
Deferred Fuel Adjustment Clause		$16.3		$16.3
Construction Costs for Development Project (a)	—		48.2
Restricted Cash (b)	8.1		2.7
Other	18.1		14.8
Total Prepayments and Other Current Assets		$42.5		$82.0

(a) Construction Costs for Development Project relate to ALLETE Clean Energy’s project to develop and construct a wind energy facility in 2015. Beginning in the second quarter of 2015, these costs have been net against contract billings. (See Billings in Excess of Costs and Estimated Earnings in 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	September 30, 2015		December 31, 2014
Millions
Customer Deposits		$17.6		$19.7
Power Purchase Agreements (a)	23.8		19.4
Construction Deposits Received for Development Project (b)	—		54.3
Billings in Excess of Costs and Estimated Earnings (c)	8.8		—
Other	44.1		27.4
Total Other Current Liabilities		$94.3		$120.8

(a) Power Purchase Agreements were acquired in conjunction with ALLETE Clean Energy’s wind energy facilities acquisitions. (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. Beginning in the second quarter of 2015, these deposits have been net against contract costs and estimated gross profit. (See Billings in Excess of Costs and Estimated Earnings below and Note 4. Acquisitions.)

(c) Billings in Excess of Costs and Estimated Earnings represents the excess of contract billings over the construction costs incurred and estimated earnings recognized. In the second quarter of 2015, the NDPSC approved the sale agreement ALLETE Clean Energy has with Montana-Dakota Utilities to develop, construct, and sell a wind energy facility in 2015. (See Note 4. Acquisitions.)

Other Non-Current Liabilities	September 30, 2015		December 31, 2014
Millions
Asset Retirement Obligation		$126.3		$109.2
Power Purchase Agreements (a)	143.9		110.7
Contingent Consideration (b)	37.4		—
Other	45.1		45.1
Total Other Non-Current Liabilities		$352.7		$265.0

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

(b) Contingent Consideration relates to the estimated fair value of the earnings-based payment resulting from the U.S. Water Services acquisition. (See Note 4. Acquisitions and Note 6. Fair Value.)

Supplemental Statement of Cash Flows Information [Table Text Block]

Supplemental Statement of Cash Flows Information.

Nine Months Ended September 30,	2015		2014
Millions
Cash Paid During the Period for Interest – Net of Amounts Capitalized		$46.6		$39.4
Cash Paid During the Period for Income Taxes		$0.1		$2.8
Noncash Investing and Financing Activities
Decrease in Accounts Payable for Capital Additions to Property, Plant and Equipment	$(26.8)		$(6.5)
Capitalized Asset Retirement Costs		$7.8		$0.6
AFUDC–Equity		$2.6		$5.9
ALLETE Common Stock Contributed to the Pension Plan	—			$19.5
Contingent Consideration		$35.7	—