Anticipated Additional Generating Capacity (MW)

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- Definition

Minnesota Next Generation Act of 2007 introduced a spend goal of 1.5% of net gross operating revenues from service provided in the state on energy CIPs each year.

+ References

No definition available.

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- Definition

Distributed Solar Energy Standard Mandate, Overall Mandate Percentage

+ References

No definition available.

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- Definition

Distributed Solar Project, Generating Production

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No definition available.

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- Definition

Energy Conservation and Optimization Plan Goal, Next Fiscal Year

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No definition available.

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- Definition

Energy Conservation and Optimization Plan Goal, Second Fiscal Year

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- Definition

The approved percentage return on common equity dedicated to the utility plant in the investee accounted for under the equity method of accounting.

+ References

No definition available.

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- Definition

The approved percentage return on common equity, including an incentive adder for participation in a regional transmission organization dedicated to the utility plant in the investee accounted for under the equity method of accounting.

+ References

No definition available.

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- Definition

FERC Authorized Return on Common Equity

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No definition available.

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- Definition

FERC Authorized Return on Equity, Including Incentive Adder

+ References

No definition available.

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- Definition

The length of notice required to terminate a contract (in years).

+ References

No definition available.

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- Definition

Number of Customers

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No definition available.

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- Definition

Minnesota's solar energy mandate for total retail electric sales, excluding sales to certain industrial customers, by the end of 2020.

+ References

No definition available.

+ Details

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- Definition

Minnesota's solar energy mandate for small scale solar with photovoltaic devices with a nameplate capacity of 20 kilowatts or less by the end of 2020. Expressed as a percentage of the overall mandate.

+ References

No definition available.

+ Details

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- Definition

Solar Project, Generating Production

+ References

No definition available.

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- Definition

Current regulatory liabilities generally represent obligations to make refunds to customers for various reasons including overpayment.

+ References

No definition available.

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- Definition

The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
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-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482099/360-10-50-1

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- Definition

Percentage of public utility's approved equity to capital, including debt and equity.

+ References

No definition available.

+ Details

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's approved return on equity.

+ References

No definition available.

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Percentage of public utility's requested equity to capital, including debt and equity.

+ References

No definition available.

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- Definition

Amount of public utility's requested rate increase (decrease) with regulatory agency.

+ References

No definition available.

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- Definition

Percentage of public utility's requested rate increase (decrease) with regulatory agency.

+ References

No definition available.

+ Details

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- Definition

Percentage of public utility's requested return on equity.

+ References

No definition available.

+ Details

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- Definition

The amount of regulated other operating revenues recognized during the period.

+ References

No definition available.

+ Details

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- Definition

Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
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-URI https://asc.fasb.org/1943274/2147477571/980-405-25-1

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- Definition

The amount for the individual regulatory noncurrent liability as itemized in a table of regulatory noncurrent liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
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-Section S99
-Paragraph 1
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Regulatory Matters - Narrative (Details) $ in Thousands								3 Months Ended	12 Months Ended			36 Months Ended
Regulatory Matters - Narrative (Details) $ in Thousands	May 03, 2024 USD ($)	Mar. 29, 2024 USD ($)	Dec. 19, 2023 USD ($)	Nov. 01, 2023 USD ($)	Oct. 01, 2023	Feb. 28, 2023	Dec. 20, 2022 USD ($)	Mar. 31, 2025	Dec. 31, 2024 USD ($) contract customer MW	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)	Jan. 30, 2025 MW	Oct. 17, 2024	Dec. 15, 2023 MW	Oct. 02, 2023 MW	Sep. 30, 2023 USD ($)	Feb. 01, 2021 MW
Regulatory Matters [Line Items]
Regulatory asset									$ 371,700	$ 425,400
Regulatory liability									570,500	574,000
Depreciation									$ 271,300	251,700	$ 242,000
ATC
Regulatory Matters [Line Items]
Authorized return on equity									10.02%
Authorized return on equity, including incentive adder									10.52%					10.48%
Solar Project
Regulatory Matters [Line Items]
Solar project, generating production (MW) \| MW																119.5
Minnesota Power \| Solar Generation
Regulatory Matters [Line Items]
Solar project, generating production (MW) \| MW																300
Minnesota Power \| Solar Generation \| Subsequent Event
Regulatory Matters [Line Items]
Distributed solar project, generating production (MW) \| MW													10
Minnesota Power \| Solar Project
Regulatory Matters [Line Items]
Solar project, generating production (MW) \| MW																85
Minnesota Power \| Wind Generation
Regulatory Matters [Line Items]
Solar project, generating production (MW) \| MW															400
Minnesota Power \| Maximum \| Solar Generation
Regulatory Matters [Line Items]
Distributed solar project, generating production (MW) \| MW									85
Minnesota Power \| Minimum \| Solar Generation
Regulatory Matters [Line Items]
Distributed solar project, generating production (MW) \| MW									65
MPUC
Regulatory Matters [Line Items]
Minnesota solar energy standard - overall mandate percentage									1.50%
MPUC \| Minimum
Regulatory Matters [Line Items]
Cip spending minimum - percentage									1.50%
Minnesota solar energy standard - overall mandate percentage									1.50%
Minnesota solar energy standard - small scale solar mandate percentage									10.00%
Distributed Minnesota solar energy standard - overall mandate percentage									3.00%
MPUC \| Minnesota Power \| Solar Generation
Regulatory Matters [Line Items]
Generating capacity (MW) \| MW									40
FERC
Regulatory Matters [Line Items]
FERC authorized return on common equity									10.02%
FERC authorized return on equity including incentive adder									10.52%
Authorized return on equity														9.98%
2021 Integrated Resource Plan \| MPUC \| Maximum \| Renewable Generation
Regulatory Matters [Line Items]
Generating capacity (MW) \| MW																		700
CIP Consolidated Filing Member \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Revenue from cost recovery riders									$ 2,200
CIP Consolidated Filing \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Revenue from cost recovery riders										2,200	1,900
ECO Triennial Filing \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Conservation improvement program goal, next fiscal year									12,700
Energy conservation and optimization plan goal, second fiscal year									12,800
Electric Rates \| Fuel Adjustment Clause 2022 \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Regulatory asset											13,000	$ 13,000
Electric Rates \| Fuel Adjustment Clause 2023 \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Regulatory liability									4,500	15,500
Retail Customers \| Deferred Accounting Petition \| MPUC
Regulatory Matters [Line Items]
Depreciation									4,200
Retail Customers \| 2018 Wisconsin General Rate Case \| PSCW \| SWL&P
Regulatory Matters [Line Items]
Requested return on equity		10.40%
Requested equity ratio		55.00%
Retail Customers \| 2022 Wisconsin General Rate Case \| PSCW \| SWL&P
Regulatory Matters [Line Items]
Authorized return on equity							10.00%					10.00%
Return on common equity							55.00%					55.00%
Additional revenue from base rates							$ 3,300
Retail Customers \| 2024 Wisconsin General Rate Case \| PSCW \| SWL&P
Regulatory Matters [Line Items]
Authorized return on equity												9.80%
Return on common equity												55.00%
Requested return on equity		10.00%
Requested equity ratio		55.00%
Requested average rate increase		5.90%
Annual additional revenue generated from requested final rate increase		$ 7,300
Additional revenue from base rates		$ 5,500
Retail Customers \| Electric Rates \| Current Cost Recovery Rider \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Revenue from cost recovery riders									20,000	$ 57,000	$ 38,800
Retail Customers \| Electric Rates \| 2016 Minnesota General Rate Review \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Authorized return on equity											9.25%
Return on common equity											53.81%
Retail Customers \| Electric Rates \| 2022 Minnesota General Rate Review \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Authorized return on equity					9.65%	9.65%
Return on common equity					52.50%	52.50%
Customer refund											$ 18,000	$ 18,000					$ 39,000
Retail Customers \| Electric Rates \| 2024 Minnesota General Rate Case \| MPUC \| Minnesota Power
Regulatory Matters [Line Items]
Requested return on equity	9.78%			10.30%
Requested equity ratio	53.00%			53.00%
Requested average rate increase				12.00%
Annual additional revenue generated from requested final rate increase	$ 33,970		$ 64,000	$ 89,000
Regulatory liabilities									$ 23,000
Retail Customers \| Electric Rates \| 2024 Minnesota General Rate Case \| MPUC \| Minnesota Power \| Subsequent Event
Regulatory Matters [Line Items]
Requested return on equity								9.78%
Requested equity ratio								53.00%
Municipal Customers \| Electric Rates \| FERC-Approved Wholesale Rates \| FERC \| Minnesota Power
Regulatory Matters [Line Items]
Number of customers \| customer									14
Notice required to terminate									3 years
Municipal Customers \| Electric Rates \| FERC-Approved Wholesale Rates \| FERC \| Minnesota Power \| Wholesale Electric Contract (Cost-Based Formula Methodology for Entire Term)
Regulatory Matters [Line Items]
Number of customers \| contract									2
Municipal Customers \| Electric Rates \| FERC-Approved Wholesale Rates \| FERC \| Minnesota Power \| Wholesale Electric Contracts (Through 2029)
Regulatory Matters [Line Items]
Number of customers \| customer									13