Operations and Significant Accounting Policies (Tables)

9 Months Ended

Sep. 30, 2022

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 amounts presented in the Consolidated Statement of Cash Flows.

Cash, Cash Equivalents and Restricted Cash	September 30, 2022	December 31, 2021	September 30, 2021	December 31, 2020
Millions
Cash and Cash Equivalents	$42.1	$45.1	$59.0	$44.3
Restricted Cash included in Prepayments and Other	4.2	0.3	4.1	0.8
Restricted Cash included in Other Non-Current Assets	2.3	2.3	2.3	20.1
Cash, Cash Equivalents and Restricted Cash on the Consolidated Statement of Cash Flows	$48.6	$47.7	$65.4	$65.2

Inventories – Net [Table Text Block]

Inventories – Net	September 30, 2022	December 31, 2021
Millions
Fuel (a)	$36.2	$18.7
Materials and Supplies	70.6	56.1
Renewable Energy Facilities Under Development (b)	365.4	22.9
Total Inventories – Net	$472.2	$97.7

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

(b)    Renewable Energy Facilities Under Development consists primarily of project costs related to ALLETE Clean Energy’s Northern Wind, Rock Aetna, and Red Barn wind projects which are expected to be sold in late 2022 and early 2023, respectively. (See Other Current Liabilities.)

Other Non-Current Assets [Table Text Block]

Other Non-Current Assets	September 30, 2022	December 31, 2021
Millions
Contract Assets (a)	$21.5	$23.3
Operating Lease Right-of-use Assets	13.9	16.4
ALLETE Properties	17.6	19.4
Restricted Cash	2.3	2.3
Other Postretirement Benefit Plans	66.5	64.8
Other	79.8	86.7
Total Other Non-Current Assets	$201.6	$212.9

(a)    Contract Assets consist of 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, 2022	December 31, 2021
Millions
Customer Deposits (a)	$111.7	$27.2
PSAs	6.1	12.6
Manufactured Gas Plant (b)	17.8	12.8
Fuel Adjustment Clause	—	5.0
Operating Lease Liabilities	3.7	4.8
Redeemable Non-Controlling Interest (c)	—	30.6
Other	49.2	40.0
Total Other Current Liabilities	$188.5	$133.0

(a) Primarily related to deposits received by ALLETE Clean Energy for the Northern Wind, Rock Aetna and Red Barn wind projects which are expected to be sold in late 2022 and early 2023, respectively. (See Inventories – Net.)

(b) The manufactured gas plant represents the current liability for remediation of a former manufactured gas plant site located in Superior, Wisconsin, and formerly operated by SWL&P.

(c) Amount reclassified from Non-Controlling Interest in Subsidiaries resulting from the exercise of an option to buy out a non-controlling interest, which was paid in the first quarter of 2022.

Other Non-Current Liabilities [Table Text Block]

Other Non-Current Liabilities	September 30, 2022	December 31, 2021
Millions
Asset Retirement Obligation (a)	$197.2	$184.5
PSAs	28.4	39.5
Manufactured Gas Plant (b)	0.2	5.2
Operating Lease Liabilities	10.0	11.6
Other	33.0	40.0
Total Other Non-Current Liabilities	$268.8	$280.8

(a)The asset retirement obligation is primarily related to our Regulated Operations and is funded through customer rates over the life of the related assets. Additionally, BNI Energy funds its obligation through its cost-plus coal supply agreements for which BNI Energy has recorded a receivable of $28.5 million in Other Non-Current Assets on the Consolidated Balance Sheet as of September 30, 2022, ($28.5 million as of December 31, 2021).

(b)The manufactured gas plant represents the non-current liability for remediation of a former manufactured gas plant site located in Superior, Wisconsin, and formerly operated by SWL&P.

Other Income [Table Text Block]

	Quarter Ended		Nine Months Ended
	September 30,		September 30,
Other Income	2022	2021	2022	2021
Millions
Pension and Other Postretirement Benefit Plan Non-Service Credits (a)	$1.9	$1.6	$7.2	$4.4
Interest and Investment Income (Loss)	(0.4)	(0.1)	(1.3)	1.7
AFUDC - Equity	0.7	0.6	2.4	1.7
PSA Liability (b)	—	—	10.2	—
Other	0.1	(1.1)	(2.1)	(1.7)
Total Other Income	$2.3	$1.0	$16.4	$6.1

(a)These are components of net periodic pension and other postretirement benefit cost other than service cost. (See Note 10. Pension and Other Postretirement Benefit Plans.)

(b)The gain on removal of the PSA liability for the Northern Wind project upon decommissioning of the legacy wind energy facility assets, which was fully offset by a reserve for an anticipated loss on the sale of the Northern Wind project.

Supplemental Statement of Cash Flows Information [Table Text Block]

Supplemental Statement of Cash Flows Information.

Nine Months Ended September 30,	2022	2021
Millions
Cash Paid for Interest – Net of Amounts Capitalized	$60.5	$54.9
Noncash Investing and Financing Activities
Increase (Decrease) in Accounts Payable for Capital Additions to Property, Plant and Equipment	$2.4	$(12.1)
Reclassification of Property, Plant and Equipment to Inventory (a)	$99.8	—
Capitalized Asset Retirement Costs	$9.0	$3.5
AFUDC–Equity	$2.4	$1.7

(a)The decommissioning of the existing Northern Wind assets resulted in a reclassification from Property, Plant and Equipment – Net to Inventories – Net in the second quarter of 2022 as they are being sold to a subsidiary of Xcel Energy Inc. In the third quarter of 2022, safe harbor equipment was transferred to the project entity resulting in an additional reclassification from Property, Plant and Equipment - Net to Inventories - Net.