Operations and Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2018

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Cash, Cash Equivalents and Restricted Cash [Table Text Block]

The following table provides a reconciliation of cash, cash equivalents and restricted cash reported within the Consolidated Balance Sheet that aggregate to the amount presented in the Consolidated Statement of Cash Flows. During the first quarter of 2018, the Company updated the presentation of its Consolidated Statement of Cash Flows to include restricted cash with cash and cash equivalents when reconciling the beginning-of-period and end-of-period total amounts shown on the Consolidated Statement of Cash Flows. (See Recently Adopted Pronouncements - Statement of Cash Flows: Restricted Cash.)

Cash, Cash Equivalents and Restricted Cash	September 30, 2018		December 31, 2017		September 30, 2017		December 31, 2016
Millions
Cash and Cash Equivalents		$128.0		$98.9		$104.4		$27.5
Restricted Cash included in Prepayments and Other	4.8		2.6		6.5		2.2
Restricted Cash included in Other Non-Current Assets	8.7		8.6		8.6		8.6
Cash, Cash Equivalents and Restricted Cash on the Consolidated Statement of Cash Flows		$141.5		$110.1		$119.5		$38.3

Inventories – Net [Table Text Block]

Inventories – Net	September 30, 2018			December 31, 2017
Millions
Fuel (a)		$27.3			$34.8
Materials and Supplies	44.0			46.5
Construction of Wind Energy Facility (b)	66.7			—
Raw Materials	3.1			2.8
Work in Progress	5.5			4.2
Finished Goods	9.0			8.3
Reserve for Obsolescence	(0.8		)	(0.7		)
Total Inventories – Net		$154.8			$95.9

(a) Fuel consists primarily of coal inventory at Minnesota Power.

(b) On February 28, 2018, Montana-Dakota Utilities exercised its option to purchase the Thunder Spirit II wind energy facility upon completion, resulting in a reclassification of the project costs from Property, Plant and Equipment – Net to Inventories – Net as ALLETE Clean Energy will not own the facility upon completion.

Other Non-Current Assets [Table Text Block]

Other Non-Current Assets	September 30, 2018		December 31, 2017
Millions
Contract Assets (a)		$31.1		$31.6
Finance Receivable	10.4		11.0
Other	62.9		65.1
Total Other Non-Current Assets		$104.4		$107.7

(a)

Contract Assets include payments made to customers as an incentive to execute or extend service agreements. The contract payments are being amortized over the term of the respective agreements as a reduction to revenue.

Other Current Liabilities [Table Text Block]

Other Current Liabilities	September 30, 2018		December 31, 2017
Millions
Provision for Interim Rate Refund (a)		$36.7	—
Contract Liabilities (b)	22.7			$8.7
PSAs	15.4		24.5
Provision for Tax Reform Refund (c)	9.2		—
Contingent Consideration (d)	5.7		—
Other	55.2		50.0
Total Other Current Liabilities		$144.9		$83.2

(a) Provision for Interim Rate Refund is expected to be refunded to Minnesota Power’s regulated retail customers in the first quarter of 2019 and includes $20.8 million of discounts provided to EITE customers that will be offset against interim rate refunds as of September 30, 2018 ($8.6 million as of December 31, 2017). (See Note 6. Regulatory Matters.)

(b) Contract Liabilities include deposits received as a result of entering into contracts with our customers prior to completing our performance obligations.

(c) Provision for Tax Reform Refund is expected to be refunded to Minnesota Power customers in the first quarter of 2019 and SWL&P customers in 2019 pending the outcome of SWL&P’s rate filing with the PSCW. (See Note 6. Regulatory Matters.)

(d)

Contingent Consideration relates to the estimated fair value of the earnings-based payment resulting from the U.S. Water Services acquisition. (See Note 5. Fair Value.)

Other Non-Current Liabilities [Table Text Block]

Other Non-Current Liabilities	September 30, 2018		December 31, 2017
Millions
Asset Retirement Obligation		$138.3		$122.7
PSAs	80.0		89.5
Contingent Consideration (a)	—		5.4
Other	47.3		49.5
Total Other Non-Current Liabilities		$265.6		$267.1

(a) Contingent Consideration relates to the estimated fair value of the earnings-based payment resulting from the U.S. Water Services acquisition. (See Note 5. Fair Value.)

Supplemental Statement of Cash Flows Information [Table Text Block]

Supplemental Statement of Cash Flows Information.

Nine Months Ended September 30,	2018		2017
Millions
Cash Paid for Interest – Net of Amounts Capitalized		$52.9		$51.4
Noncash Investing and Financing Activities
Increase (Decrease) in Accounts Payable for Capital Additions to Property, Plant and Equipment	$(14.4)			$1.2
Reclassification of Property, Plant and Equipment to Inventory (a)		$46.3	—
Capitalized Asset Retirement Costs		$15.4		$19.7
AFUDC–Equity		$0.9		$0.7
ALLETE Common Stock Contributed to the Pension Plans	—			$13.5

(a) On February 28, 2018, Montana-Dakota Utilities exercised its option to purchase the Thunder Spirit II wind energy facility upon completion, resulting in a reclassification of the project costs from Property, Plant and Equipment – Net to Inventories – Net as ALLETE Clean Energy will not own the facility upon completion.