Operations and Significant Accounting Policies (Tables)

12 Months Ended

Dec. 31, 2022

Organization, Consolidation and Presentation of Financial Statements [Abstract]

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

Cash, Cash Equivalents and Restricted Cash
As of December 31	2022	2021	2020
Millions
Cash and Cash Equivalents	$36.4	$45.1	$44.3
Restricted Cash included in Prepayments and Other	1.5	0.3	0.8
Restricted Cash included in Other Non-Current Assets	2.3	2.3	20.1
Cash, Cash Equivalents and Restricted Cash on the Consolidated Statement of Cash Flows	$40.2	$47.7	$65.2

Supplemental Statement of Cash Flow Information [Table Text Block]

Supplemental Statement of Cash Flow Information.

Consolidated Statement of Cash Flows
Year Ended December 31	2022	2021	2020
Millions
Cash Paid During the Period for Interest – Net of Amounts Capitalized	$72.8	$66.8	$62.0
Cash Paid (Received) for Income Taxes	$6.0	—	$(2.0)
Noncash Investing and Financing Activities
Increase (Decrease) in Accounts Payable for Capital Additions to Property, Plant and Equipment	$(9.6)	$(14.0)	$(67.0)
Reclassification of Property, Plant and Equipment to Inventory (a)	$99.7	—	—
Reclassification of Redeemable Non-Controlling Interest to Current Liabilities (b)	—	$30.6	—
Capitalized Asset Retirement Costs	$11.8	$16.9	$4.1
AFUDC–Equity	$2.7	$2.6	$1.9

(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 were repowered and subsequently 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.

(b)Amount reclassified to Current Liabilities resulting from the exercise of an option to buy out a non-controlling interest.

Accounts Receivable [Table Text Block]

Accounts Receivable
As of December 31	2022	2021
Millions
Trade Accounts Receivable
Billed	$107.1	$100.6
Unbilled	29.2	24.7
Less: Allowance for Doubtful Accounts	1.6	1.8
Total Trade Accounts Receivable	134.7	123.5
Income Taxes Receivable	3.2	0.2
Total Accounts Receivable	$137.9	$123.7

Inventories – Net [Table Text Block]

Inventories – Net
As of December 31	2022	2021
Millions
Fuel (a)	$33.4	$18.7
Materials and Supplies	75.1	56.1
Construction of Wind Energy Facilities (b)	347.4	22.9
Total Inventories – Net	$455.9	$97.7

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

(b) Project costs related to ALLETE Clean Energy’s Northern Wind project sold in January 2023 and Red Barn wind project which is expected to be sold in the first half 2023. (See Other Current Liabilities.)

Other Non-Current Assets [Table Text Block]

Other Non-Current Assets
As of December 31	2022	2021
Millions
Contract Assets (a)	$21.0	$23.3
Operating Lease Right-of-use Assets	12.7	16.4
ALLETE Properties	19.1	19.4
Restricted Cash	2.3	2.3
Other Postretirement Benefit Plans	58.8	64.8
Other	90.4	86.7
Total Other Non-Current Assets	$204.3	$212.9

(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
As of December 31	2022	2021
Millions
Customer Deposits (a)	$150.7	$27.2
PSAs	6.1	12.6
Provision for Interim Rate Refund	18.4	—
Manufactured Gas Plant (b)	14.7	12.8
Fuel Adjustment Clause	—	5.0
Operating Lease Liabilities	3.2	4.8
Redeemable Non-Controlling Interest (c)	—	30.6
Other	57.9	40.0
Total Other Current Liabilities	$251.0	$133.0

(a)    Primarily related to deposits received by ALLETE Clean Energy for the Northern Wind project sold in January 2023 and the Red Barn wind project which is expected to be sold in the first half of 2023. (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. (See Note 9. Commitments, Guarantees and Contingencies.)

(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
As of December 31	2022	2021
Millions
Asset Retirement Obligation (a)	$200.4	$184.5
PSAs	26.9	39.5
Operating Lease Liabilities	9.3	11.6
Other	32.4	45.2
Total Other Non-Current Liabilities	$269.0	$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 $32.4 million in Other Non-Current Assets on the Consolidated Balance Sheet as of December 31, 2022 ($28.5 million as of December 31, 2021).

NOTE 1. OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Continued)

Lease, Cost [Table Text Block]

Additional information on the components of lease cost and presentation of cash flows were as follows:

As December 31	2022	2021
Millions
Operating Lease Cost	$6.3	$6.7
Other Information:
Operating Cash Flows From Operating Leases	$6.3	$6.7

Additional information related to leases was as follows:

As of December 31	2022		2021
Millions
Balance Sheet Information Related to Leases:
Other Non-Current Assets	$12.7		$16.4
Total Operating Lease Right-of-use Assets	$12.7		$16.4
Other Current Liabilities	$3.2		$4.8
Other Non-Current Liabilities	9.3		11.6
Total Operating Lease Liabilities	$12.5		$16.4
Weighted Average Remaining Lease Term (Years):
Operating Leases - Vehicles and Equipment	4		3
Operating Leases - Land and Other	16		27
Weighted Average Discount Rate:
Operating Leases - Vehicles and Equipment	3.9	%	3.8	%
Operating Leases - Land and Other	3.9	%	4.5	%

NOTE 1. OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Continued)

Lessee, Operating Lease, Liability, Maturity [Table Text Block]

Maturities of lease liabilities were as follows:

	December 31, 2022
Millions
2023	$3.4
2024	3.1
2025	2.9
2026	2.9
2027	3.8
Thereafter	1.2
Total Lease Payments Due	17.3
Less: Imputed Interest	4.8
Total Lease Obligations	12.5
Less: Current Lease Obligations	3.2
Total Long-term Lease Obligations	$9.3

Other Income (Expense) - Other [Table Text Block]

Other Income (Expense) - Other
Year Ended December 31	2022	2021	2020
Millions
Pension and Other Postretirement Benefit Plan Non-Service Credit (a)	$9.8	$6.1	$8.6
Interest and Investment Earnings	—	2.3	1.6
AFUDC - Equity	2.7	2.6	1.9
Gain on Land Sales	—	0.1	0.4
PSA Liability (b)	10.2	—	—
Other	(0.3)	(2.4)	2.2
Total Other Income (Expense) - Other	$22.4	$8.7	$14.7

(a)These are components of net periodic pension and other postretirement benefit cost other than service cost. (See Note 12. 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 more than offset by a reserve for an anticipated loss on the sale of the Northern Wind project, was recorded in Cost of Sales - Non-Utility on the Consolidated Statement of Income.

Schedule of Error Corrections and Prior Period Adjustments

A summary of the effect of the revision on the Consolidated Statements of Income and Consolidated Statement of Comprehensive Income for the year ended December 31, 2020 is as follows:

Revision Impacts for the Year Ended December 31, 2020	As Reported	Adjustment	As Revised
Millions Except Per Share Amounts
Impairment of Property, Plant and Equipment	—	$12.7	$12.7
Income Tax Benefit	$(39.5)	(3.9)	(43.4)
Net Income Attributable to ALLETE	$174.2	$(8.8)	$165.4
Comprehensive Income Attributable to ALLETE	$166.7	$(8.8)	$157.9
Diluted Earnings Per Share	$3.35	$(0.17)	$3.18

NOTE 1. OPERATIONS AND SIGNIFICANT ACCOUNTING POLICIES (Continued)

A summary of the effect of the revision on the Consolidated Balance Sheet as of December 31, 2021 is as follows:

Revision Impacts for the Year Ended December 31, 2021	As Reported	Adjustment	As Revised
Millions
Property, Plant and Equipment - Net	$5,100.2	$(12.7)	$5,087.5
Total Assets	$6,435.0	$(12.7)	$6,422.3
Deferred Income Taxes	$185.7	$(3.9)	$181.8
Total Liabilities	$3,488.7	$(3.9)	$3,484.8
Retained Earnings	$900.2	$(8.8)	$891.4
Total Equity	$2,946.3	$(8.8)	$2,937.5