context
stringlengths
21
33.9k
category
stringclasses
2 values
entity
stringlengths
1
12
entity_type
stringclasses
5 values
query
stringlengths
97
3.31k
answer
stringlengths
12
169
On April 15, 2022, a wholly-owned subsidiary of ALLETE acquired 100 percent of the membership interests of New Energy for a purchase price of $ 165.5 million. Total consideration of approximately $ 158.8 million was paid in cash on the acquisition date, which is net of cash acquired and debt assumed. New Energy, which ...
text
100
percentItemType
text: <entity> 100 </entity> <entity type> percentItemType </entity type> <context> On April 15, 2022, a wholly-owned subsidiary of ALLETE acquired 100 percent of the membership interests of New Energy for a purchase price of $ 165.5 million. Total consideration of approximately $ 158.8 million was paid in cash on the ...
us-gaap:BusinessAcquisitionPercentageOfVotingInterestsAcquired
On April 15, 2022, a wholly-owned subsidiary of ALLETE acquired 100 percent of the membership interests of New Energy for a purchase price of $ 165.5 million. Total consideration of approximately $ 158.8 million was paid in cash on the acquisition date, which is net of cash acquired and debt assumed. New Energy, which ...
text
158.8
monetaryItemType
text: <entity> 158.8 </entity> <entity type> monetaryItemType </entity type> <context> On April 15, 2022, a wholly-owned subsidiary of ALLETE acquired 100 percent of the membership interests of New Energy for a purchase price of $ 165.5 million. Total consideration of approximately $ 158.8 million was paid in cash on t...
us-gaap:BusinessCombinationConsiderationTransferred1
For tax purpose, the purchase price allocation resulted in $ 154.9 million of deductible goodwill.
text
154.9
monetaryItemType
text: <entity> 154.9 </entity> <entity type> monetaryItemType </entity type> <context> For tax purpose, the purchase price allocation resulted in $ 154.9 million of deductible goodwill. </context>
us-gaap:BusinessAcquisitionPurchasePriceAllocationGoodwillExpectedTaxDeductibleAmount
Acquisition-related costs were $ 2.7 million after-tax, expensed as incurred during 2022 and recorded in Operating and Maintenance on the Consolidated Statement of Income.
text
2.7
monetaryItemType
text: <entity> 2.7 </entity> <entity type> monetaryItemType </entity type> <context> Acquisition-related costs were $ 2.7 million after-tax, expensed as incurred during 2022 and recorded in Operating and Maintenance on the Consolidated Statement of Income. </context>
us-gaap:BusinessCombinationAcquisitionRelatedCosts
Our wholly-owned subsidiary, ALLETE Transmission Holdings, owns approximately 8 percent of ATC, a Wisconsin-based utility that owns and maintains electric transmission assets in portions of Wisconsin, Michigan, Minnesota and Illinois. We account for our investment in ATC under the equity method of accounting. In 2024, ...
text
8
percentItemType
text: <entity> 8 </entity> <entity type> percentItemType </entity type> <context> Our wholly-owned subsidiary, ALLETE Transmission Holdings, owns approximately 8 percent of ATC, a Wisconsin-based utility that owns and maintains electric transmission assets in portions of Wisconsin, Michigan, Minnesota and Illinois. We ...
us-gaap:EquityMethodInvestmentOwnershipPercentage
Our wholly-owned subsidiary, ALLETE Transmission Holdings, owns approximately 8 percent of ATC, a Wisconsin-based utility that owns and maintains electric transmission assets in portions of Wisconsin, Michigan, Minnesota and Illinois. We account for our investment in ATC under the equity method of accounting. In 2024, ...
text
5.8
monetaryItemType
text: <entity> 5.8 </entity> <entity type> monetaryItemType </entity type> <context> Our wholly-owned subsidiary, ALLETE Transmission Holdings, owns approximately 8 percent of ATC, a Wisconsin-based utility that owns and maintains electric transmission assets in portions of Wisconsin, Michigan, Minnesota and Illinois. ...
us-gaap:PaymentsToAcquireEquityMethodInvestments
Our subsidiary, ALLETE South Wind, owns a 49 percent equity interest in Nobles 2, the entity that owns and operates a 250 MW wind energy facility in southwestern Minnesota pursuant to a 20 -year PPA with Minnesota Power. We account for our investment in Nobles 2 under the equity method of accounting.
text
49
percentItemType
text: <entity> 49 </entity> <entity type> percentItemType </entity type> <context> Our subsidiary, ALLETE South Wind, owns a 49 percent equity interest in Nobles 2, the entity that owns and operates a 250 MW wind energy facility in southwestern Minnesota pursuant to a 20 -year PPA with Minnesota Power. We account for o...
us-gaap:EquityMethodInvestmentOwnershipPercentage
The Company also recorded net loss attributable to non-controlling interest of $ 11.7 million related to its investment in Nobles 2.
text
11.7
monetaryItemType
text: <entity> 11.7 </entity> <entity type> monetaryItemType </entity type> <context> The Company also recorded net loss attributable to non-controlling interest of $ 11.7 million related to its investment in Nobles 2. </context>
us-gaap:NetIncomeLossAttributableToNoncontrollingInterest
As of December 31, 2024, the aggregate amount of available-for-sale corporate and governmental debt securities maturing in one year or less was $ 2.0 million, in one year to less than three years was $ 2.8 million, in three years to less than five years was $ 1.5 million and in five or more years was $ 0.5 million.
text
2.0
monetaryItemType
text: <entity> 2.0 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, the aggregate amount of available-for-sale corporate and governmental debt securities maturing in one year or less was $ 2.0 million, in one year to less than three years was $ 2.8 million, in three years to le...
us-gaap:AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue
The aggregate carrying amount of our equity investments was $ 340.1 million as of December 31, 2024 ($ 331.2 million as of December 31, 2023). The Company assesses our equity investments in ATC and Nobles 2 for impairment whenever events or changes in circumstances indicate that the carrying amount of our investments m...
text
340.1
monetaryItemType
text: <entity> 340.1 </entity> <entity type> monetaryItemType </entity type> <context> The aggregate carrying amount of our equity investments was $ 340.1 million as of December 31, 2024 ($ 331.2 million as of December 31, 2023). The Company assesses our equity investments in ATC and Nobles 2 for impairment whenever ev...
us-gaap:EquityMethodInvestments
The aggregate carrying amount of our equity investments was $ 340.1 million as of December 31, 2024 ($ 331.2 million as of December 31, 2023). The Company assesses our equity investments in ATC and Nobles 2 for impairment whenever events or changes in circumstances indicate that the carrying amount of our investments m...
text
331.2
monetaryItemType
text: <entity> 331.2 </entity> <entity type> monetaryItemType </entity type> <context> The aggregate carrying amount of our equity investments was $ 340.1 million as of December 31, 2024 ($ 331.2 million as of December 31, 2023). The Company assesses our equity investments in ATC and Nobles 2 for impairment whenever ev...
us-gaap:EquityMethodInvestments
The Company assesses the impairment of goodwill annually in the fourth quarter and whenever an event occurs or circumstances change that would indicate that the carrying amount may be impaired. The Company’s goodwill is a result of the New Energy acquisition in 2022. (See Note 1. Operations and Significant Accounting P...
text
154.9
monetaryItemType
text: <entity> 154.9 </entity> <entity type> monetaryItemType </entity type> <context> The Company assesses the impairment of goodwill annually in the fourth quarter and whenever an event occurs or circumstances change that would indicate that the carrying amount may be impaired. The Company’s goodwill is a result of t...
us-gaap:Goodwill
As of December 31, 2024, total short-term debt outstanding was $ 94.7 million ($ 111.4 million as of December 31, 2023), and consisted of long-term debt due within one year and included no unamortized debt issuance costs.
text
94.7
monetaryItemType
text: <entity> 94.7 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total short-term debt outstanding was $ 94.7 million ($ 111.4 million as of December 31, 2023), and consisted of long-term debt due within one year and included no unamortized debt issuance costs. </context>
us-gaap:DebtCurrent
As of December 31, 2024, total short-term debt outstanding was $ 94.7 million ($ 111.4 million as of December 31, 2023), and consisted of long-term debt due within one year and included no unamortized debt issuance costs.
text
111.4
monetaryItemType
text: <entity> 111.4 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total short-term debt outstanding was $ 94.7 million ($ 111.4 million as of December 31, 2023), and consisted of long-term debt due within one year and included no unamortized debt issuance costs. </context>
us-gaap:DebtCurrent
As of December 31, 2024, total short-term debt outstanding was $ 94.7 million ($ 111.4 million as of December 31, 2023), and consisted of long-term debt due within one year and included no unamortized debt issuance costs.
text
no
monetaryItemType
text: <entity> no </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total short-term debt outstanding was $ 94.7 million ($ 111.4 million as of December 31, 2023), and consisted of long-term debt due within one year and included no unamortized debt issuance costs. </context>
us-gaap:DeferredFinanceCostsCurrentNet
As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of credit and $ 20.0 million outstanding draws under our lines of credit as of December 3...
text
362.0
monetaryItemType
text: <entity> 362.0 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of...
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of credit and $ 20.0 million outstanding draws under our lines of credit as of December 3...
text
423.1
monetaryItemType
text: <entity> 423.1 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of...
us-gaap:LineOfCreditFacilityMaximumBorrowingCapacity
As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of credit and $ 20.0 million outstanding draws under our lines of credit as of December 3...
text
16.2
monetaryItemType
text: <entity> 16.2 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of ...
us-gaap:LettersOfCreditOutstandingAmount
As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of credit and $ 20.0 million outstanding draws under our lines of credit as of December 3...
text
20.0
monetaryItemType
text: <entity> 20.0 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of ...
us-gaap:LinesOfCreditCurrent
As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of credit and $ 20.0 million outstanding draws under our lines of credit as of December 3...
text
19.4
monetaryItemType
text: <entity> 19.4 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of ...
us-gaap:LettersOfCreditOutstandingAmount
As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of credit and $ 20.0 million outstanding draws under our lines of credit as of December 3...
text
34.1
monetaryItemType
text: <entity> 34.1 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had consolidated bank lines of credit aggregating to $ 362.0 million ($ 423.1 million as of December 31, 2023), most of which expire in January 2027. We had $ 16.2 million outstanding in standby letters of ...
us-gaap:LinesOfCreditCurrent
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
1704.7
monetaryItemType
text: <entity> 1704.7 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturi...
us-gaap:LongTermDebtNoncurrent
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
1679.9
monetaryItemType
text: <entity> 1679.9 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturi...
us-gaap:LongTermDebtNoncurrent
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
8.6
monetaryItemType
text: <entity> 8.6 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing ...
us-gaap:DeferredFinanceCostsNoncurrentNet
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
94.7
monetaryItemType
text: <entity> 94.7 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing...
us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
80.2
monetaryItemType
text: <entity> 80.2 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing...
us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
182.5
monetaryItemType
text: <entity> 182.5 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturin...
us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
55.8
monetaryItemType
text: <entity> 55.8 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing...
us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
220.3
monetaryItemType
text: <entity> 220.3 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturin...
us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive
As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturing in 2025 is $ 94.7 million; $ 80.2 million in 2026; $ 182.5 million in 2027; $ 55.8 mi...
text
1174.5
monetaryItemType
text: <entity> 1174.5 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, total long-term debt outstanding was $ 1,704.7 million ($ 1,679.9 million as of December 31, 2023) and included $ 8.6 million of unamortized debt issuance costs. The aggregate amount of long-term debt maturi...
us-gaap:LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive
Minnesota Power is obligated to make financing payments for the Camp Ripley solar array totaling $ 1.4 million annually during the financing term, which expires in 2027. Minnesota Power has the option at the end of the financing term to renew for a two -year term, or to purchase the solar array for approximately $ 4 mi...
text
1.4
monetaryItemType
text: <entity> 1.4 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power is obligated to make financing payments for the Camp Ripley solar array totaling $ 1.4 million annually during the financing term, which expires in 2027. Minnesota Power has the option at the end of the financing term t...
us-gaap:DebtInstrumentPeriodicPayment
On April 23, 2024, ALLETE issued $ 100 million of its First Mortgage Bonds (Bonds) to certain institutional buyers in the private placement market. The Bonds, which bear interest at 5.72 percent, will mature on April 30, 2039 and pay interest semi-annually in April and October of each year, commencing on October 30, 20...
text
100
monetaryItemType
text: <entity> 100 </entity> <entity type> monetaryItemType </entity type> <context> On April 23, 2024, ALLETE issued $ 100 million of its First Mortgage Bonds (Bonds) to certain institutional buyers in the private placement market. The Bonds, which bear interest at 5.72 percent, will mature on April 30, 2039 and pay i...
us-gaap:ProceedsFromIssuanceOfFirstMortgageBond
On April 23, 2024, ALLETE issued $ 100 million of its First Mortgage Bonds (Bonds) to certain institutional buyers in the private placement market. The Bonds, which bear interest at 5.72 percent, will mature on April 30, 2039 and pay interest semi-annually in April and October of each year, commencing on October 30, 20...
text
5.72
percentItemType
text: <entity> 5.72 </entity> <entity type> percentItemType </entity type> <context> On April 23, 2024, ALLETE issued $ 100 million of its First Mortgage Bonds (Bonds) to certain institutional buyers in the private placement market. The Bonds, which bear interest at 5.72 percent, will mature on April 30, 2039 and pay i...
us-gaap:DebtInstrumentInterestRateStatedPercentage
On July 31, 2024, ALLETE issued a notice to the holders of its 2.65 percent senior notes due September 10, 2025, (“2025 Notes”) regarding the Company’s exercise of its option to prepay all of the issued and outstanding 2025 Notes. ALLETE prepaid all $ 150 million in aggregate principal amount of the 2025 Notes on Septe...
text
2.65
percentItemType
text: <entity> 2.65 </entity> <entity type> percentItemType </entity type> <context> On July 31, 2024, ALLETE issued a notice to the holders of its 2.65 percent senior notes due September 10, 2025, (“2025 Notes”) regarding the Company’s exercise of its option to prepay all of the issued and outstanding 2025 Notes. ALLE...
us-gaap:DebtInstrumentInterestRateStatedPercentage
On July 31, 2024, ALLETE issued a notice to the holders of its 2.65 percent senior notes due September 10, 2025, (“2025 Notes”) regarding the Company’s exercise of its option to prepay all of the issued and outstanding 2025 Notes. ALLETE prepaid all $ 150 million in aggregate principal amount of the 2025 Notes on Septe...
text
150
monetaryItemType
text: <entity> 150 </entity> <entity type> monetaryItemType </entity type> <context> On July 31, 2024, ALLETE issued a notice to the holders of its 2.65 percent senior notes due September 10, 2025, (“2025 Notes”) regarding the Company’s exercise of its option to prepay all of the issued and outstanding 2025 Notes. ALLE...
us-gaap:RepaymentsOfSeniorDebt
On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended, to institutional accredited i...
text
150
monetaryItemType
text: <entity> 150 </entity> <entity type> monetaryItemType </entity type> <context> On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Sec...
us-gaap:DebtInstrumentFaceAmount
On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended, to institutional accredited i...
text
100
monetaryItemType
text: <entity> 100 </entity> <entity type> monetaryItemType </entity type> <context> On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Sec...
us-gaap:DebtInstrumentFaceAmount
On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended, to institutional accredited i...
text
5.94
percentItemType
text: <entity> 5.94 </entity> <entity type> percentItemType </entity type> <context> On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Sec...
us-gaap:DebtInstrumentInterestRateStatedPercentage
On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended, to institutional accredited i...
text
50
monetaryItemType
text: <entity> 50 </entity> <entity type> monetaryItemType </entity type> <context> On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Sect...
us-gaap:DebtInstrumentFaceAmount
On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Section 4(a)(2) of the Securities Act of 1933, as amended, to institutional accredited i...
text
6.18
percentItemType
text: <entity> 6.18 </entity> <entity type> percentItemType </entity type> <context> On September 5, 2024, ALLETE issued and sold $ 150 million of senior unsecured notes (“Notes”) to certain institutional buyers in the private placement market. The Notes were sold in reliance on an exemption from registration under Sec...
us-gaap:DebtInstrumentInterestRateStatedPercentage
Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fired generating unit. Minnesota Power’s output entitlement under the Agreement is 50 per...
text
50
percentItemType
text: <entity> 50 </entity> <entity type> percentItemType </entity type> <context> Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fired ...
us-gaap:LongTermContractForPurchaseOfElectricPowerShareOfPlantOutputBeingPurchased
Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fired generating unit. Minnesota Power’s output entitlement under the Agreement is 50 per...
text
168.9
monetaryItemType
text: <entity> 168.9 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fi...
us-gaap:LongTermContractForPurchaseOfElectricPowerAmountOfLongTermDebtOrLeaseObligationOutstanding
Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fired generating unit. Minnesota Power’s output entitlement under the Agreement is 50 per...
text
30.6
monetaryItemType
text: <entity> 30.6 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fir...
us-gaap:LongTermContractForPurchaseOfElectricPowerAnnualMinimumDebtServicePaymentRequired
Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fired generating unit. Minnesota Power’s output entitlement under the Agreement is 50 per...
text
32.1
monetaryItemType
text: <entity> 32.1 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power has a PPA with Square Butte that extends through 2026 (Agreement). Minnesota Power is obligated to pay its pro rata share of Square Butte’s costs based on its entitlement to the output of Square Butte’s 455 MW coal fir...
us-gaap:LongTermContractForPurchaseOfElectricPowerAnnualMinimumDebtServicePaymentRequired
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
87.7
monetaryItemType
text: <entity> 87.7 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 pe...
us-gaap:UtilitiesOperatingExpensePurchasedPowerUnderLongTermContracts
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
86.2
monetaryItemType
text: <entity> 86.2 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 pe...
us-gaap:UtilitiesOperatingExpensePurchasedPowerUnderLongTermContracts
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
82.7
monetaryItemType
text: <entity> 82.7 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 pe...
us-gaap:UtilitiesOperatingExpensePurchasedPowerUnderLongTermContracts
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
50
percentItemType
text: <entity> 50 </entity> <entity type> percentItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 perce...
us-gaap:LongTermContractForPurchaseOfElectricPowerShareOfPlantOutputBeingPurchased
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
4.9
monetaryItemType
text: <entity> 4.9 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 per...
us-gaap:LongTermContractForPurchaseOfElectricPowerInterestIncludedInContractCharges
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
5.5
monetaryItemType
text: <entity> 5.5 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 per...
us-gaap:LongTermContractForPurchaseOfElectricPowerInterestIncludedInContractCharges
Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 percent output entitlement. Included in this amount was Minnesota Power’s pro rata share...
text
5.1
monetaryItemType
text: <entity> 5.1 </entity> <entity type> monetaryItemType </entity type> <context> Minnesota Power’s cost of power purchased from Square Butte during 2024 was $ 87.7 million ($ 86.2 million in 2023; $ 82.7 million in 2022). This reflects Minnesota Power’s pro rata share of total Square Butte costs based on the 50 per...
us-gaap:LongTermContractForPurchaseOfElectricPowerInterestIncludedInContractCharges
Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, it so...
text
50
percentItemType
text: <entity> 50 </entity> <entity type> percentItemType </entity type> <context> Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is elimi...
us-gaap:LongTermContractForPurchaseOfElectricPowerShareOfPlantOutputBeingPurchased
Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, it so...
text
41
percentItemType
text: <entity> 41 </entity> <entity type> percentItemType </entity type> <context> Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is elimi...
us-gaap:LongTermContractForPurchaseOfElectricPowerShareOfPlantOutputBeingPurchased
Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, it so...
text
37
percentItemType
text: <entity> 37 </entity> <entity type> percentItemType </entity type> <context> Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is elimi...
us-gaap:LongTermContractForPurchaseOfElectricPowerShareOfPlantOutputBeingPurchased
Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is eliminated at the end of 2025. Of Minnesota Power’s 50 percent output entitlement, it so...
text
32
percentItemType
text: <entity> 32 </entity> <entity type> percentItemType </entity type> <context> Minnesota Power is selling a portion of its entitlement from Square Butte to Minnkota Power, resulting in Minnkota Power’s net entitlement increasing and Minnesota Power’s net entitlement decreasing until Minnesota Power’s share is elimi...
us-gaap:LongTermContractForPurchaseOfElectricPowerShareOfPlantOutputBeingPurchased
In 2015, the EPA published a final rule (2015 Rule) regulating CCR as nonhazardous waste under Subtitle D of the Resource Conservation and Recovery Act (RCRA) in the Federal Register. The rule included additional requirements for new landfill and impoundment construction as well as closure activities related to certain...
text
65
monetaryItemType
text: <entity> 65 </entity> <entity type> monetaryItemType </entity type> <context> In 2015, the EPA published a final rule (2015 Rule) regulating CCR as nonhazardous waste under Subtitle D of the Resource Conservation and Recovery Act (RCRA) in the Federal Register. The rule included additional requirements for new la...
us-gaap:SiteContingencyLossExposureNotAccruedBestEstimate
In 2015, the EPA published a final rule (2015 Rule) regulating CCR as nonhazardous waste under Subtitle D of the Resource Conservation and Recovery Act (RCRA) in the Federal Register. The rule included additional requirements for new landfill and impoundment construction as well as closure activities related to certain...
text
120
monetaryItemType
text: <entity> 120 </entity> <entity type> monetaryItemType </entity type> <context> In 2015, the EPA published a final rule (2015 Rule) regulating CCR as nonhazardous waste under Subtitle D of the Resource Conservation and Recovery Act (RCRA) in the Federal Register. The rule included additional requirements for new l...
us-gaap:SiteContingencyLossExposureNotAccruedBestEstimate
On May 8, 2024, the EPA's final CCR Legacy Impoundment Rule was published in the Federal Register. The final rule expands the scope of units regulated under the CCR rule to include legacy ponds (inactive surface impoundments at inactive facilities) and creates a new category of units called CCR management units (CCRMU)...
text
50
monetaryItemType
text: <entity> 50 </entity> <entity type> monetaryItemType </entity type> <context> On May 8, 2024, the EPA's final CCR Legacy Impoundment Rule was published in the Federal Register. The final rule expands the scope of units regulated under the CCR rule to include legacy ponds (inactive surface impoundments at inactive...
us-gaap:SiteContingencyLossExposureNotAccruedBestEstimate
On May 8, 2024, the EPA's final CCR Legacy Impoundment Rule was published in the Federal Register. The final rule expands the scope of units regulated under the CCR rule to include legacy ponds (inactive surface impoundments at inactive facilities) and creates a new category of units called CCR management units (CCRMU)...
text
85
monetaryItemType
text: <entity> 85 </entity> <entity type> monetaryItemType </entity type> <context> On May 8, 2024, the EPA's final CCR Legacy Impoundment Rule was published in the Federal Register. The final rule expands the scope of units regulated under the CCR rule to include legacy ponds (inactive surface impoundments at inactive...
us-gaap:SiteContingencyLossExposureNotAccruedBestEstimate
We have multiple credit facility agreements in place that provide the ability to issue standby letters of credit to satisfy our contractual security requirements across our businesses. As of December 31, 2024, we had $ 134.7 million of outstanding letters of credit issued, including those issued under our revolving cre...
text
134.7
monetaryItemType
text: <entity> 134.7 </entity> <entity type> monetaryItemType </entity type> <context> We have multiple credit facility agreements in place that provide the ability to issue standby letters of credit to satisfy our contractual security requirements across our businesses. As of December 31, 2024, we had $ 134.7 million ...
us-gaap:LettersOfCreditOutstandingAmount
We have multiple credit facility agreements in place that provide the ability to issue standby letters of credit to satisfy our contractual security requirements across our businesses. As of December 31, 2024, we had $ 134.7 million of outstanding letters of credit issued, including those issued under our revolving cre...
text
122.2
monetaryItemType
text: <entity> 122.2 </entity> <entity type> monetaryItemType </entity type> <context> We have multiple credit facility agreements in place that provide the ability to issue standby letters of credit to satisfy our contractual security requirements across our businesses. As of December 31, 2024, we had $ 134.7 million ...
us-gaap:LettersOfCreditOutstandingAmount
. As of December 31, 2024, BNI Energy had surety bonds outstanding of $ 88.8 million related to the reclamation liability for closing costs associated with its mine and mine facilities. Although its coal supply agreements obligate the customers to provide for the closing costs, additional assurance is required by feder...
text
82.1
monetaryItemType
text: <entity> 82.1 </entity> <entity type> monetaryItemType </entity type> <context> . As of December 31, 2024, BNI Energy had surety bonds outstanding of $ 88.8 million related to the reclamation liability for closing costs associated with its mine and mine facilities. Although its coal supply agreements obligate the...
us-gaap:GuaranteeObligationsMaximumExposure
. Nobles 2 wind energy facility requires standby letters of credit as security for certain contractual obligations. As of December 31, 2024, ALLETE South Wind has $ 10.1 million outstanding in standby letters of credit, related to our portion of the security requirements relative to our ownership in Nobles 2.
text
10.1
monetaryItemType
text: <entity> 10.1 </entity> <entity type> monetaryItemType </entity type> <context> . Nobles 2 wind energy facility requires standby letters of credit as security for certain contractual obligations. As of December 31, 2024, ALLETE South Wind has $ 10.1 million outstanding in standby letters of credit, related to our...
us-gaap:LettersOfCreditOutstandingAmount
. As of December 31, 2024, South Shore Energy had $ 29.7 million outstanding in standby letters of credit pledged as security in connection with the development of NTEC.
text
29.7
monetaryItemType
text: <entity> 29.7 </entity> <entity type> monetaryItemType </entity type> <context> . As of December 31, 2024, South Shore Energy had $ 29.7 million outstanding in standby letters of credit pledged as security in connection with the development of NTEC. </context>
us-gaap:LettersOfCreditOutstandingAmount
. As of December 31, 2024, ALLETE Properties had surety bonds outstanding to governmental entities totaling $ 2.0 million primarily related to development and maintenance obligations for various projects. The estimated cost of the remaining development work is $ 1.0 million. ALLETE Properties does not believe it is lik...
text
1.0
monetaryItemType
text: <entity> 1.0 </entity> <entity type> monetaryItemType </entity type> <context> . As of December 31, 2024, ALLETE Properties had surety bonds outstanding to governmental entities totaling $ 2.0 million primarily related to development and maintenance obligations for various projects. The estimated cost of the rema...
us-gaap:GuaranteeObligationsMaximumExposure
In 2005, the Town Center District issued $ 26.4 million of tax-exempt, 6.0 percent capital improvement revenue bonds. The capital improvement revenue bonds are payable over 31 years (by May 1, 2036) and are secured by special assessments on the benefited land. To the extent that ALLETE Properties still owns land at the...
text
26.4
monetaryItemType
text: <entity> 26.4 </entity> <entity type> monetaryItemType </entity type> <context> In 2005, the Town Center District issued $ 26.4 million of tax-exempt, 6.0 percent capital improvement revenue bonds. The capital improvement revenue bonds are payable over 31 years (by May 1, 2036) and are secured by special assessme...
us-gaap:FairValueDisclosureOffbalanceSheetRisksFaceAmountLiability
. In the first quarter of 2023, an ALLETE Clean Energy subsidiary initiated arbitration proceedings seeking damages against a counterparty for non-performance under a contract. Arbitration hearings were held in June and July 2023, and a final arbitration ruling was issued in favor of ALLETE Clean Energy’s subsidiary in...
text
60
monetaryItemType
text: <entity> 60 </entity> <entity type> monetaryItemType </entity type> <context> . In the first quarter of 2023, an ALLETE Clean Energy subsidiary initiated arbitration proceedings seeking damages against a counterparty for non-performance under a contract. Arbitration hearings were held in June and July 2023, and a...
us-gaap:ProceedsFromLegalSettlements
We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value, of which 2.1 million shares remain available for issuance as of December 31, 2024. ...
text
no
sharesItemType
text: <entity> no </entity> <entity type> sharesItemType </entity type> <context> We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value, o...
us-gaap:StockIssuedDuringPeriodSharesOther
We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value, of which 2.1 million shares remain available for issuance as of December 31, 2024. ...
text
none
sharesItemType
text: <entity> none </entity> <entity type> sharesItemType </entity type> <context> We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value,...
us-gaap:StockIssuedDuringPeriodSharesOther
We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value, of which 2.1 million shares remain available for issuance as of December 31, 2024. ...
text
3.7
sharesItemType
text: <entity> 3.7 </entity> <entity type> sharesItemType </entity type> <context> We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value, ...
us-gaap:StockIssuedDuringPeriodSharesNewIssues
We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value, of which 2.1 million shares remain available for issuance as of December 31, 2024. ...
text
224
monetaryItemType
text: <entity> 224 </entity> <entity type> monetaryItemType </entity type> <context> We entered into a distribution agreement with Lampert Capital Markets, in 2008, as amended most recently in 2020, with respect to the issuance and sale of up to an aggregate of 13.6 million shares of our common stock, without par value...
us-gaap:StockIssuedDuringPeriodValueNewIssues
The effective tax rate was an expense of 3.7 percent for 2024 (expense of 13.5 percent for 2023; benefit of 31.2 percent for 2022). The 2024, 2023 and 2022 effective tax rates were primarily impacted by tax credits and non-controlling interests in subsidiaries.
text
3.7
percentItemType
text: <entity> 3.7 </entity> <entity type> percentItemType </entity type> <context> The effective tax rate was an expense of 3.7 percent for 2024 (expense of 13.5 percent for 2023; benefit of 31.2 percent for 2022). The 2024, 2023 and 2022 effective tax rates were primarily impacted by tax credits and non-controlling i...
us-gaap:EffectiveIncomeTaxRateContinuingOperations
The effective tax rate was an expense of 3.7 percent for 2024 (expense of 13.5 percent for 2023; benefit of 31.2 percent for 2022). The 2024, 2023 and 2022 effective tax rates were primarily impacted by tax credits and non-controlling interests in subsidiaries.
text
13.5
percentItemType
text: <entity> 13.5 </entity> <entity type> percentItemType </entity type> <context> The effective tax rate was an expense of 3.7 percent for 2024 (expense of 13.5 percent for 2023; benefit of 31.2 percent for 2022). The 2024, 2023 and 2022 effective tax rates were primarily impacted by tax credits and non-controlling ...
us-gaap:EffectiveIncomeTaxRateContinuingOperations
The effective tax rate was an expense of 3.7 percent for 2024 (expense of 13.5 percent for 2023; benefit of 31.2 percent for 2022). The 2024, 2023 and 2022 effective tax rates were primarily impacted by tax credits and non-controlling interests in subsidiaries.
text
31.2
percentItemType
text: <entity> 31.2 </entity> <entity type> percentItemType </entity type> <context> The effective tax rate was an expense of 3.7 percent for 2024 (expense of 13.5 percent for 2023; benefit of 31.2 percent for 2022). The 2024, 2023 and 2022 effective tax rates were primarily impacted by tax credits and non-controlling ...
us-gaap:EffectiveIncomeTaxRateContinuingOperations
Pre-tax amounts; state NOL carryforwards net of a $ 9.7 million valuation allowance.
text
9.7
monetaryItemType
text: <entity> 9.7 </entity> <entity type> monetaryItemType </entity type> <context> Pre-tax amounts; state NOL carryforwards net of a $ 9.7 million valuation allowance. </context>
us-gaap:OperatingLossCarryforwardsValuationAllowance
Net of a $ 42.3 million valuation allowance as of December 31, 2024 ($ 55.4 million as of December 31, 2023).
text
42.3
monetaryItemType
text: <entity> 42.3 </entity> <entity type> monetaryItemType </entity type> <context> Net of a $ 42.3 million valuation allowance as of December 31, 2024 ($ 55.4 million as of December 31, 2023). </context>
us-gaap:TaxCreditCarryforwardValuationAllowance
Net of a $ 42.3 million valuation allowance as of December 31, 2024 ($ 55.4 million as of December 31, 2023).
text
55.4
monetaryItemType
text: <entity> 55.4 </entity> <entity type> monetaryItemType </entity type> <context> Net of a $ 42.3 million valuation allowance as of December 31, 2024 ($ 55.4 million as of December 31, 2023). </context>
us-gaap:TaxCreditCarryforwardValuationAllowance
The federal tax credit carryforward periods expire between 2035 and 2044. We expect to fully utilize the tax credit carryforwards; therefore, no federal valuation allowance has been recognized as of December 31, 2024. The apportioned state NOL, capital loss and tax credit carryforward periods expire between 2025 and 20...
text
no
monetaryItemType
text: <entity> no </entity> <entity type> monetaryItemType </entity type> <context> The federal tax credit carryforward periods expire between 2035 and 2044. We expect to fully utilize the tax credit carryforwards; therefore, no federal valuation allowance has been recognized as of December 31, 2024. The apportioned st...
us-gaap:OperatingLossCarryforwardsValuationAllowance
Unrecognized tax benefits are the differences between a tax position taken or expected to be taken in a tax return and the benefit recognized and measured pursuant to the “more-likely-than-not” criteria. The unrecognized tax benefit balance includes permanent tax positions which, if recognized, would affect the annual ...
text
0.6
monetaryItemType
text: <entity> 0.6 </entity> <entity type> monetaryItemType </entity type> <context> Unrecognized tax benefits are the differences between a tax position taken or expected to be taken in a tax return and the benefit recognized and measured pursuant to the “more-likely-than-not” criteria. The unrecognized tax benefit ba...
us-gaap:UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate
As of December 31, 2024, we had accrued interest of $ 0.2 million ($ 0.1 million as of December 31, 2023; none as of December 31, 2022) related to unrecognized tax benefits included on the Consolidated Balance Sheet due to our NOL carryforwards. We classify interest related to unrecognized tax benefits as interest expe...
text
0.2
monetaryItemType
text: <entity> 0.2 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had accrued interest of $ 0.2 million ($ 0.1 million as of December 31, 2023; none as of December 31, 2022) related to unrecognized tax benefits included on the Consolidated Balance Sheet due to our NOL carr...
us-gaap:UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued
As of December 31, 2024, we had accrued interest of $ 0.2 million ($ 0.1 million as of December 31, 2023; none as of December 31, 2022) related to unrecognized tax benefits included on the Consolidated Balance Sheet due to our NOL carryforwards. We classify interest related to unrecognized tax benefits as interest expe...
text
0.1
monetaryItemType
text: <entity> 0.1 </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had accrued interest of $ 0.2 million ($ 0.1 million as of December 31, 2023; none as of December 31, 2022) related to unrecognized tax benefits included on the Consolidated Balance Sheet due to our NOL carr...
us-gaap:UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued
As of December 31, 2024, we had accrued interest of $ 0.2 million ($ 0.1 million as of December 31, 2023; none as of December 31, 2022) related to unrecognized tax benefits included on the Consolidated Balance Sheet due to our NOL carryforwards. We classify interest related to unrecognized tax benefits as interest expe...
text
none
monetaryItemType
text: <entity> none </entity> <entity type> monetaryItemType </entity type> <context> As of December 31, 2024, we had accrued interest of $ 0.2 million ($ 0.1 million as of December 31, 2023; none as of December 31, 2022) related to unrecognized tax benefits included on the Consolidated Balance Sheet due to our NOL car...
us-gaap:UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued
No material changes to unrecognized tax benefits are expected during the next 12 months.
text
No
monetaryItemType
text: <entity> No </entity> <entity type> monetaryItemType </entity type> <context> No material changes to unrecognized tax benefits are expected during the next 12 months. </context>
us-gaap:SignificantChangeInUnrecognizedTaxBenefitsIsReasonablyPossibleAmountOfUnrecordedBenefit
We have noncontributory union, non-union and combined retiree defined benefit pension plans covering eligible employees. The combined retiree defined benefit pension plan was created in 2016, to include all union and non-union retirees from the existing plans as of January 2016. The plans provide defined benefits based...
text
15.7
monetaryItemType
text: <entity> 15.7 </entity> <entity type> monetaryItemType </entity type> <context> We have noncontributory union, non-union and combined retiree defined benefit pension plans covering eligible employees. The combined retiree defined benefit pension plan was created in 2016, to include all union and non-union retiree...
us-gaap:EmployeeStockOwnershipPlanESOPCompensationExpense
We have noncontributory union, non-union and combined retiree defined benefit pension plans covering eligible employees. The combined retiree defined benefit pension plan was created in 2016, to include all union and non-union retirees from the existing plans as of January 2016. The plans provide defined benefits based...
text
13.7
monetaryItemType
text: <entity> 13.7 </entity> <entity type> monetaryItemType </entity type> <context> We have noncontributory union, non-union and combined retiree defined benefit pension plans covering eligible employees. The combined retiree defined benefit pension plan was created in 2016, to include all union and non-union retiree...
us-gaap:EmployeeStockOwnershipPlanESOPCompensationExpense
We have noncontributory union, non-union and combined retiree defined benefit pension plans covering eligible employees. The combined retiree defined benefit pension plan was created in 2016, to include all union and non-union retirees from the existing plans as of January 2016. The plans provide defined benefits based...
text
12.0
monetaryItemType
text: <entity> 12.0 </entity> <entity type> monetaryItemType </entity type> <context> We have noncontributory union, non-union and combined retiree defined benefit pension plans covering eligible employees. The combined retiree defined benefit pension plan was created in 2016, to include all union and non-union retiree...
us-gaap:EmployeeStockOwnershipPlanESOPCompensationExpense
We have postretirement health care and life insurance plans covering eligible employees. In 2010, the postretirement health care plan was closed to employees hired after January 2011, and the eligibility requirements were amended. The postretirement life plan was amended in 2014 to close the plan to non-union employees...
text
no
monetaryItemType
text: <entity> no </entity> <entity type> monetaryItemType </entity type> <context> We have postretirement health care and life insurance plans covering eligible employees. In 2010, the postretirement health care plan was closed to employees hired after January 2011, and the eligibility requirements were amended. The p...
us-gaap:PensionAndOtherPostretirementBenefitContributions
We have postretirement health care and life insurance plans covering eligible employees. In 2010, the postretirement health care plan was closed to employees hired after January 2011, and the eligibility requirements were amended. The postretirement life plan was amended in 2014 to close the plan to non-union employees...
text
none
monetaryItemType
text: <entity> none </entity> <entity type> monetaryItemType </entity type> <context> We have postretirement health care and life insurance plans covering eligible employees. In 2010, the postretirement health care plan was closed to employees hired after January 2011, and the eligibility requirements were amended. The...
us-gaap:PensionAndOtherPostretirementBenefitContributions
Management considers various factors when making funding decisions such as regulatory requirements, actuarially determined minimum contribution requirements and contributions required to avoid benefit restrictions for the pension plans. Contributions are based on estimates and assumptions which are subject to change. O...
text
19.1
monetaryItemType
text: <entity> 19.1 </entity> <entity type> monetaryItemType </entity type> <context> Management considers various factors when making funding decisions such as regulatory requirements, actuarially determined minimum contribution requirements and contributions required to avoid benefit restrictions for the pension plan...
us-gaap:DefinedBenefitPlanContributionsByEmployer
Management considers various factors when making funding decisions such as regulatory requirements, actuarially determined minimum contribution requirements and contributions required to avoid benefit restrictions for the pension plans. Contributions are based on estimates and assumptions which are subject to change. O...
text
not
monetaryItemType
text: <entity> not </entity> <entity type> monetaryItemType </entity type> <context> Management considers various factors when making funding decisions such as regulatory requirements, actuarially determined minimum contribution requirements and contributions required to avoid benefit restrictions for the pension plans...
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear
Management considers various factors when making funding decisions such as regulatory requirements, actuarially determined minimum contribution requirements and contributions required to avoid benefit restrictions for the pension plans. Contributions are based on estimates and assumptions which are subject to change. O...
text
no
monetaryItemType
text: <entity> no </entity> <entity type> monetaryItemType </entity type> <context> Management considers various factors when making funding decisions such as regulatory requirements, actuarially determined minimum contribution requirements and contributions required to avoid benefit restrictions for the pension plans....
us-gaap:DefinedBenefitPlanExpectedFutureEmployerContributionsNextFiscalYear
The pension costs that are reported as a component within the Consolidated Balance Sheet, reflected in long-term regulatory assets or liabilities and accumulated other comprehensive income, consist primarily of a net loss of $ 235.2 million as of December 31, 2024 (net loss of $ 256.9 million as of December 31, 2023).
text
235.2
monetaryItemType
text: <entity> 235.2 </entity> <entity type> monetaryItemType </entity type> <context> The pension costs that are reported as a component within the Consolidated Balance Sheet, reflected in long-term regulatory assets or liabilities and accumulated other comprehensive income, consist primarily of a net loss of $ 235.2 ...
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
The pension costs that are reported as a component within the Consolidated Balance Sheet, reflected in long-term regulatory assets or liabilities and accumulated other comprehensive income, consist primarily of a net loss of $ 235.2 million as of December 31, 2024 (net loss of $ 256.9 million as of December 31, 2023).
text
256.9
monetaryItemType
text: <entity> 256.9 </entity> <entity type> monetaryItemType </entity type> <context> The pension costs that are reported as a component within the Consolidated Balance Sheet, reflected in long-term regulatory assets or liabilities and accumulated other comprehensive income, consist primarily of a net loss of $ 235.2 ...
us-gaap:DefinedBenefitPlanAccumulatedOtherComprehensiveIncomeNetGainsLossesBeforeTax
According to the accounting standards for retirement benefits, only assets in the VEBAs are treated as plan assets in the preceding table for the purpose of determining funded status. In addition to the postretirement health and life assets reported in the previous table, we had $ 13.4 million in irrevocable grantor tr...
text
13.4
monetaryItemType
text: <entity> 13.4 </entity> <entity type> monetaryItemType </entity type> <context> According to the accounting standards for retirement benefits, only assets in the VEBAs are treated as plan assets in the preceding table for the purpose of determining funded status. In addition to the postretirement health and life ...
us-gaap:LongTermInvestments
According to the accounting standards for retirement benefits, only assets in the VEBAs are treated as plan assets in the preceding table for the purpose of determining funded status. In addition to the postretirement health and life assets reported in the previous table, we had $ 13.4 million in irrevocable grantor tr...
text
12.8
monetaryItemType
text: <entity> 12.8 </entity> <entity type> monetaryItemType </entity type> <context> According to the accounting standards for retirement benefits, only assets in the VEBAs are treated as plan assets in the preceding table for the purpose of determining funded status. In addition to the postretirement health and life ...
us-gaap:LongTermInvestments
There were no shares of ALLETE common stock included in pension plan equity securities as of December 31, 2024 ( no shares as of December 31, 2023).
text
no
sharesItemType
text: <entity> no </entity> <entity type> sharesItemType </entity type> <context> There were no shares of ALLETE common stock included in pension plan equity securities as of December 31, 2024 ( no shares as of December 31, 2023). </context>
us-gaap:DefinedBenefitPlanNumberOfSharesOfEquitySecuritiesIssuedByEmployerAndRelatedPartiesIncludedInPlanAssets
We sponsor an ESOP within the RSOP. Eligible employees may contribute to the RSOP plan as of their date of hire. The dividends received by the ESOP are distributed to participants. Dividends on allocated ESOP shares are recorded as a reduction of retained earnings. ESOP employer allocations are funded with contribution...
text
15.7
monetaryItemType
text: <entity> 15.7 </entity> <entity type> monetaryItemType </entity type> <context> We sponsor an ESOP within the RSOP. Eligible employees may contribute to the RSOP plan as of their date of hire. The dividends received by the ESOP are distributed to participants. Dividends on allocated ESOP shares are recorded as a ...
us-gaap:EmployeeStockOwnershipPlanESOPCompensationExpense
We sponsor an ESOP within the RSOP. Eligible employees may contribute to the RSOP plan as of their date of hire. The dividends received by the ESOP are distributed to participants. Dividends on allocated ESOP shares are recorded as a reduction of retained earnings. ESOP employer allocations are funded with contribution...
text
13.7
monetaryItemType
text: <entity> 13.7 </entity> <entity type> monetaryItemType </entity type> <context> We sponsor an ESOP within the RSOP. Eligible employees may contribute to the RSOP plan as of their date of hire. The dividends received by the ESOP are distributed to participants. Dividends on allocated ESOP shares are recorded as a ...
us-gaap:EmployeeStockOwnershipPlanESOPCompensationExpense
We sponsor an ESOP within the RSOP. Eligible employees may contribute to the RSOP plan as of their date of hire. The dividends received by the ESOP are distributed to participants. Dividends on allocated ESOP shares are recorded as a reduction of retained earnings. ESOP employer allocations are funded with contribution...
text
12.0
monetaryItemType
text: <entity> 12.0 </entity> <entity type> monetaryItemType </entity type> <context> We sponsor an ESOP within the RSOP. Eligible employees may contribute to the RSOP plan as of their date of hire. The dividends received by the ESOP are distributed to participants. Dividends on allocated ESOP shares are recorded as a ...
us-gaap:EmployeeStockOwnershipPlanESOPCompensationExpense
Under our Executive Long-Term Incentive Compensation Plan (Executive Plan), share-based awards may be issued to key employees through a broad range of methods, including non-qualified and incentive stock options, performance shares, performance units, restricted stock, restricted stock units, stock appreciation rights ...
text
0.7
sharesItemType
text: <entity> 0.7 </entity> <entity type> sharesItemType </entity type> <context> Under our Executive Long-Term Incentive Compensation Plan (Executive Plan), share-based awards may be issued to key employees through a broad range of methods, including non-qualified and incentive stock options, performance shares, perf...
us-gaap:CommonStockCapitalSharesReservedForFutureIssuance