$ALE
ALLETE INC Stock $ale

$ale Overview Financials Valuation SEC Filings Company Website

2023 Q1 Form 10-K Financial Statement

#000006675623000005 Filed on February 16, 2023

Income Statement

Concept	2023 Q1	2022 Q4	2022
Revenue	$564.9M	$425.8M	$1.571B
YoY Change	47.3%	6.72%	10.68%
Cost Of Revenue	$210.5M	$85.90M	$182.8M
YoY Change	1138.24%	309.05%	165.7%
Gross Profit	$354.4M	$339.9M	$1.388B
YoY Change	-3.3%	-10.08%	2.78%
Gross Profit Margin	62.74%	79.83%	88.36%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$62.30M	$62.70M	$242.2M
YoY Change	0.97%	3.29%	4.53%
% of Gross Profit	17.58%	18.45%	17.45%
Operating Expenses	$306.1M	$306.1M	$1.251B
YoY Change	-2.24%	-6.68%	4.33%
Operating Profit	$48.30M	$33.70M	$134.2M
YoY Change	-9.55%	-32.6%	-11.3%
Interest Expense	$19.30M	-$13.00M	$75.20M
YoY Change	5.46%	18.18%	8.83%
% of Operating Profit	39.96%	-38.58%	56.04%
Other Income/Expense, Net	-$9.200M	$4.400M	-$34.10M
YoY Change	-14.81%	131.58%	-15.59%
Pretax Income	$39.10M	$25.40M	$100.1M
YoY Change	-8.22%	-38.05%	-9.74%
Income Tax	$1.500M	-$11.80M	-$31.20M
% Of Pretax Income	3.84%	-46.46%	-31.17%
Net Earnings	$58.20M	$51.70M	$189.3M
YoY Change	-12.22%	-16.48%	11.88%
Net Earnings / Revenue	10.3%	12.14%	12.05%
Basic Earnings Per Share	$1.02	$0.90	$3.38
Diluted Earnings Per Share	$1.02	$0.90	$3.38
COMMON SHARES
Basic Shares Outstanding	57.25M shares		55.90M shares
Diluted Shares Outstanding	57.30M shares		56.00M shares

Balance Sheet

Concept	2023 Q1	2022 Q4	2022
SHORT-TERM ASSETS
Cash & Short-Term Investments	$29.90M	$36.40M	$36.40M
YoY Change	-50.25%	-19.29%	-19.29%
Cash & Equivalents	$29.90M	$36.40M	$36.40M
Short-Term Investments
Other Short-Term Assets	$72.60M	$87.80M	$87.80M
YoY Change	-31.12%	254.03%	254.03%
Inventory	$346.9M	$455.9M	$455.9M
Prepaid Expenses
Receivables	$120.3M	$134.7M	$137.9M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$569.7M	$718.0M	$718.0M
YoY Change	18.56%	146.48%	146.48%
LONG-TERM ASSETS
Property, Plant & Equipment	$4.979B	$5.004B	$5.036B
YoY Change	-1.95%	-1.89%	-1.95%
Goodwill	$154.9M	$154.9M
YoY Change
Intangibles
YoY Change
Long-Term Investments	$323.9M	$322.7M	$322.7M
YoY Change	1.03%	1.48%	1.48%
Other Assets	$207.0M	$204.3M	$592.5M
YoY Change	-2.54%	-4.04%	-11.09%
Total Long-Term Assets	$6.135B	$6.128B	$6.128B
YoY Change	0.98%	-0.26%	-0.26%
TOTAL ASSETS
Total Short-Term Assets	$569.7M	$718.0M	$718.0M
Total Long-Term Assets	$6.135B	$6.128B	$6.128B
Total Assets	$6.705B	$6.846B	$6.846B
YoY Change	2.27%	6.38%	6.38%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$84.90M	$103.0M	$103.0M
YoY Change	11.86%	-7.21%	-7.21%
Accrued Expenses	$17.90M	$23.70M	$23.70M
YoY Change	-9.14%	-4.82%	-4.82%
Deferred Revenue	$10.30M	$150.7M
YoY Change	-64.36%	454.04%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$176.4M	$272.6M	$272.6M
YoY Change	-36.57%	27.26%	27.26%
Total Short-Term Liabilities	$464.4M	$716.2M	$716.2M
YoY Change	-16.56%	31.8%	31.8%
LONG-TERM LIABILITIES
Long-Term Debt	$1.756B	$1.648B	$1.648B
YoY Change	5.16%	-6.52%	-6.52%
Other Long-Term Liabilities	$270.4M	$269.0M	$974.8M
YoY Change	-5.98%	-4.2%	-2.17%
Total Long-Term Liabilities	$2.026B	$1.917B	$2.623B
YoY Change	3.52%	-6.2%	-4.95%
TOTAL LIABILITIES
Total Short-Term Liabilities	$464.4M	$716.2M	$716.2M
Total Long-Term Liabilities	$2.026B	$1.917B	$2.623B
Total Liabilities	$3.347B	$3.497B	$4.154B
YoY Change	-1.93%	0.25%	3.28%
SHAREHOLDERS EQUITY
Retained Earnings	$954.2M	$934.8M
YoY Change	2.38%	3.84%
Common Stock	$1.786B	$1.782B
YoY Change	15.85%	15.93%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.716B	$2.692B	$2.692B
YoY Change
Total Liabilities & Shareholders Equity	$6.705B	$6.846B	$6.846B
YoY Change	2.27%	6.38%	6.38%

Cashflow Statement

Concept	2023 Q1	2022 Q4	2022
OPERATING ACTIVITIES
Net Income	$58.20M	$51.70M	$189.3M
YoY Change	-12.22%	-16.48%	11.88%
Depreciation, Depletion And Amortization	$62.30M	$62.70M	$242.2M
YoY Change	0.97%	3.29%	4.53%
Cash From Operating Activities	$92.40M	$140.1M	$221.3M
YoY Change	-2025.0%	158.01%	-16.02%
INVESTING ACTIVITIES
Capital Expenditures	$70.00M	$68.50M	$220.5M
YoY Change	22.16%	-176.97%	-53.41%
Acquisitions			$155.0M
YoY Change
Other Investing Activities	$3.900M	-$4.400M	$2.400M
YoY Change	1850.0%	-588.89%	-182.76%
Cash From Investing Activities	-$74.70M	-$72.90M	-$384.0M
YoY Change	24.29%	-17.25%	-20.86%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$248.0M
YoY Change			254.79%
Debt Paid & Issued, Net	$227.8M		$877.0M
YoY Change	-12.11%		58.62%
Cash From Financing Activities	-$18.30M	-75.60M	$155.2M
YoY Change	-119.85%	-569.57%	-24.0%
NET CHANGE
Cash From Operating Activities	$92.40M	140.1M	$221.3M
Cash From Investing Activities	-$74.70M	-72.90M	-$384.0M
Cash From Financing Activities	-$18.30M	-75.60M	$155.2M
Net Change In Cash	-$600.0K	-8.400M	-$7.500M
YoY Change	-102.2%	-52.54%	-57.14%
FREE CASH FLOW
Cash From Operating Activities	$92.40M	$140.1M	$221.3M
Capital Expenditures	$70.00M	$68.50M	$220.5M
Free Cash Flow	$22.40M	$71.60M	$800.0K
YoY Change	-136.07%	-50.03%	-100.38%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2022	dei	Entity Central Index Key EntityCentralIndexKey	0000066756
CY2022	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2022Q2	dei	Entity Public Float EntityPublicFloat	3349606300	usd
CY2023Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	57252864	shares
CY2022	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2022
CY2022	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2022	dei	Amendment Flag AmendmentFlag	false
CY2022Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2021Q4	us-gaap	Common Stock No Par Value CommonStockNoParValue	0
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	80000000.0	shares
CY2021Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	80000000.0	shares
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	57200000	shares
CY2021Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	53200000	shares
CY2022Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	57200000	shares
CY2021Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	53200000	shares
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-200000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	-100000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	100000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	100000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-3000000.0	usd
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	3100000	usd
CY2022	ale	Lengthof Notice Requiredto Terminate Contract LengthofNoticeRequiredtoTerminateContract	P4Y
CY2021	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3
CY2021	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2021	ale	Morelikelythannotdefined Morelikelythannotdefined	0.50
CY2022Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilitiesCurrent
CY2021Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilitiesCurrent
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilitiesNoncurrent
CY2021Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherLiabilitiesNoncurrent
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherAssetsNoncurrent
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2022#OtherAssetsNoncurrent
CY2021	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	usd
CY2020	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	usd
CY2020Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	0	usd
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CY2020	us-gaap	Employee Service Share Based Compensation Allocation Of Recognized Period Costs Capitalized Amount EmployeeServiceShareBasedCompensationAllocationOfRecognizedPeriodCostsCapitalizedAmount	0	usd
CY2022	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2
CY2022	dei	Document Type DocumentType	10-K
CY2022	dei	Document Annual Report DocumentAnnualReport	true
CY2022	dei	Document Period End Date DocumentPeriodEndDate	2022-12-31
CY2022	dei	Document Transition Report DocumentTransitionReport	false
CY2022	dei	Entity File Number EntityFileNumber	1-3548
CY2022	dei	Entity Registrant Name EntityRegistrantName	ALLETE, Inc.
CY2022	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MN
CY2022	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	41-0418150
CY2022	dei	Entity Address Address Line1 EntityAddressAddressLine1	30 West Superior Street
CY2022	dei	Entity Address City Or Town EntityAddressCityOrTown	Duluth
CY2022	dei	Entity Address State Or Province EntityAddressStateOrProvince	MN
CY2022	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	55802-2093
CY2022	dei	City Area Code CityAreaCode	218
CY2022	dei	Local Phone Number LocalPhoneNumber	279-5000
CY2022	dei	Security12b Title Security12bTitle	Common Stock, without par value
CY2022	dei	Trading Symbol TradingSymbol	ALE
CY2022	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2022	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2022	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2022	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2022	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2022	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2022	dei	Entity Small Business EntitySmallBusiness	false
CY2022	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2022	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2022	dei	Entity Shell Company EntityShellCompany	false
CY2022Q2	dei	Entity Public Float EntityPublicFloat	3349606300	usd
CY2023Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	57252864	shares
CY2022	dei	Auditor Name AuditorName	PricewaterhouseCoopers LLP
CY2022	dei	Auditor Location AuditorLocation	Minneapolis, MN
CY2022	dei	Auditor Firm AuditorFirmId	238
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CY2022	us-gaap	Interest Expense InterestExpense	75200000	usd
CY2021	us-gaap	Interest Expense InterestExpense	69100000	usd
CY2020	us-gaap	Interest Expense InterestExpense	65600000	usd
CY2022	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	18700000	usd
CY2021	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	20000000.0	usd
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	22100000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22400000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	8700000	usd
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	14700000	usd
CY2022	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-34100000	usd
CY2021	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-40400000	usd
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-28800000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	100100000	usd
CY2021	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	110900000	usd
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	109400000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-31200000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-26900000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-43400000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	131300000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	137800000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	152800000	usd
CY2022	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-58000000.0	usd
CY2021	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-31400000	usd
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-12600000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	189300000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	169200000	usd
CY2020	us-gaap	Net Income Loss NetIncomeLoss	165400000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55900000	shares
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52400000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51900000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56000000.0	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52500000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51900000	shares
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.23
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.18
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.23
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.18
CY2022	us-gaap	Profit Loss ProfitLoss	131300000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	137800000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	152800000	usd
CY2022	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-400000	usd
CY2021	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-100000	usd
CY2020	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	100000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	200000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-7400000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	7600000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-600000	usd
CY2021	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	7300000	usd
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-7500000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	130700000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	145100000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	145300000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-58000000.0	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-31400000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-12600000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	188700000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	176500000	usd
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	157900000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	131300000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	137800000	usd
CY2020	us-gaap	Profit Loss ProfitLoss	152800000	usd
CY2022	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2700000	usd
CY2021	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2600000	usd
CY2020	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1900000	usd
CY2022	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	-2400000	usd
CY2021	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	-2200000	usd
CY2020	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	3200000	usd
CY2022	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	-1200000	usd
CY2021	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	800000	usd
CY2020	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	1300000	usd
CY2022	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	usd
CY2021	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	usd
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	12700000	usd
CY2022	us-gaap	Depreciation Depreciation	242000000.0	usd
CY2021	us-gaap	Depreciation Depreciation	231600000	usd
CY2020	us-gaap	Depreciation Depreciation	217700000	usd
CY2022	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	7600000	usd
CY2021	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	11400000	usd
CY2020	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	11300000	usd
CY2022	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	8300000	usd
CY2021	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	9900000	usd
CY2020	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	10400000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-38500000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-26900000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-43400000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	4900000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	5900000	usd
CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	6100000	usd
CY2022	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-3000000.0	usd
CY2021	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	4300000	usd
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	100000	usd
CY2022	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1900000	usd
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1200000	usd
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	2700000	usd
CY2022	ale	Provision Payments For Tax Reform Refund ProvisionPaymentsForTaxReformRefund	0	usd
CY2021	ale	Provision Payments For Tax Reform Refund ProvisionPaymentsForTaxReformRefund	0	usd
CY2020	ale	Provision Payments For Tax Reform Refund ProvisionPaymentsForTaxReformRefund	200000	usd
CY2022	ale	Changes In Fuel Adjustment Clause Regulatory Asset And Liability ChangesInFuelAdjustmentClauseRegulatoryAssetAndLiability	15100000	usd
CY2021	ale	Changes In Fuel Adjustment Clause Regulatory Asset And Liability ChangesInFuelAdjustmentClauseRegulatoryAssetAndLiability	-56400000	usd
CY2020	ale	Changes In Fuel Adjustment Clause Regulatory Asset And Liability ChangesInFuelAdjustmentClauseRegulatoryAssetAndLiability	5000000.0	usd
CY2022	ale	Provision Payments For Interim Rate Refund ProvisionPaymentsForInterimRateRefund	18400000	usd
CY2021	ale	Provision Payments For Interim Rate Refund ProvisionPaymentsForInterimRateRefund	0	usd
CY2020	ale	Provision Payments For Interim Rate Refund ProvisionPaymentsForInterimRateRefund	0	usd
CY2022	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	14000000.0	usd
CY2021	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	13000000.0	usd
CY2020	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	18200000	usd
CY2022	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	256100000	usd
CY2021	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	23500000	usd
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	1400000	usd
CY2022	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	21500000	usd
CY2021	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	500000	usd
CY2020	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-900000	usd
CY2022	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-1300000	usd
CY2021	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	15000000.0	usd
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	11800000	usd
CY2022	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	116200000	usd
CY2021	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	28000000.0	usd
CY2020	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	11700000	usd
CY2022	us-gaap	Pension Contributions PensionContributions	0	usd
CY2021	us-gaap	Pension Contributions PensionContributions	10300000	usd
CY2020	us-gaap	Pension Contributions PensionContributions	10700000	usd
CY2022	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-24100000	usd
CY2021	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	12000000.0	usd
CY2020	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	31000000.0	usd
CY2022	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	200000	usd
CY2021	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-15000000.0	usd
CY2020	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-9500000	usd
CY2022	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	221300000	usd
CY2021	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	263500000	usd
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	299800000	usd
CY2022	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	2200000	usd
CY2021	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	6400000	usd
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	12800000	usd
CY2022	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	2400000	usd
CY2021	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	3600000	usd
CY2020	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	8700000	usd
CY2022	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	155000000.0	usd
CY2021	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	usd
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	usd
CY2022	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	5900000	usd
CY2021	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	17600000	usd
CY2020	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	99100000	usd
CY2022	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	220500000	usd
CY2021	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	479500000	usd
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	724700000	usd
CY2022	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	2400000	usd
CY2021	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-9100000	usd
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-6900000	usd
CY2022	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-384000000.0	usd
CY2021	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-485200000	usd
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-812800000	usd
CY2022	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	248000000.0	usd
CY2021	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	69900000	usd
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	18100000	usd
CY2022	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	8100000	usd
CY2021	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	usd
CY2020	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	usd
CY2022	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	785400000	usd
CY2021	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	733000000.0	usd
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	672400000	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	877000000.0	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	552900000	usd
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	488600000	usd
CY2022	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	155700000	usd
CY2021	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	90900000	usd
CY2020	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	414500000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	145900000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	131900000	usd
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	128200000	usd
CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2900000	usd
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-4800000	usd
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2500000	usd
CY2022	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	155200000	usd
CY2021	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	204200000	usd
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	485700000	usd
CY2022	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-7500000	usd
CY2021	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-17500000	usd
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-27300000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	47700000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65200000	usd
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	92500000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	40200000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	47700000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65200000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3348300000	usd
CY2021Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2937500000	usd
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2791400000	usd
CY2022	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.60
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.52
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.47
CY2022	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	36400000	usd
CY2021Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	45100000	usd
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	44300000	usd
CY2022Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	1500000	usd
CY2021Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	300000	usd
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	800000	usd
CY2022Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2021Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	20100000	usd
CY2022Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	40200000	usd
CY2021Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	47700000	usd
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65200000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	72800000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	66800000	usd
CY2020	us-gaap	Interest Paid Net InterestPaidNet	62000000.0	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	6000000.0	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	0	usd
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	-2000000.0	usd
CY2022	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	-9600000	usd
CY2021	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	-14000000.0	usd
CY2020	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	-67000000.0	usd
CY2022	ale	Reclassification Of Property Plant And Equipment To Inventory ReclassificationOfPropertyPlantAndEquipmentToInventory	99700000	usd
CY2021	ale	Reclassification Of Property Plant And Equipment To Inventory ReclassificationOfPropertyPlantAndEquipmentToInventory	0	usd
CY2020	ale	Reclassification Of Property Plant And Equipment To Inventory ReclassificationOfPropertyPlantAndEquipmentToInventory	0	usd
CY2022	ale	Non Cash Reclassification Of Redeemable Non Controlling Interest To Current Liabilities NonCashReclassificationOfRedeemableNonControllingInterestToCurrentLiabilities	0	usd
CY2021	ale	Non Cash Reclassification Of Redeemable Non Controlling Interest To Current Liabilities NonCashReclassificationOfRedeemableNonControllingInterestToCurrentLiabilities	30600000	usd
CY2020	ale	Non Cash Reclassification Of Redeemable Non Controlling Interest To Current Liabilities NonCashReclassificationOfRedeemableNonControllingInterestToCurrentLiabilities	0	usd
CY2022	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	11800000	usd
CY2021	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	16900000	usd
CY2020	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	4100000	usd
CY2022	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2700000	usd
CY2021	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2600000	usd
CY2020	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1900000	usd
CY2022Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	107100000	usd
CY2021Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	100600000	usd
CY2022Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	29200000	usd
CY2021Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	24700000	usd
CY2022Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1600000	usd
CY2021Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1800000	usd
CY2022Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	134700000	usd
CY2021Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	123500000	usd
CY2022Q4	us-gaap	Nontrade Receivables Current NontradeReceivablesCurrent	3200000	usd
CY2021Q4	us-gaap	Nontrade Receivables Current NontradeReceivablesCurrent	200000	usd
CY2022Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	137900000	usd
CY2021Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	123700000	usd
CY2022Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	33400000	usd
CY2021Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	18700000	usd
CY2022Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	75100000	usd
CY2021Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	56100000	usd
CY2022Q4	us-gaap	Other Inventory OtherInventory	347400000	usd
CY2021Q4	us-gaap	Other Inventory OtherInventory	22900000	usd
CY2022Q4	us-gaap	Inventory Net InventoryNet	455900000	usd
CY2021Q4	us-gaap	Inventory Net InventoryNet	97700000	usd
CY2022	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2022	us-gaap	Error Corrections And Prior Period Adjustments Description ErrorCorrectionsAndPriorPeriodAdjustmentsDescription	We have identified an immaterial prior period error with respect to the recognition of a non-cash impairment expense for our Northern Wind operating assets in the fourth quarter of 2020 prior to the execution of the purchase and sales agreement for a repower and sale of the wind energy facility. Specifically, the remaining net book value of the property, plant and equipment used in the recoverability test was calculated incorrectly.
CY2020	ale	Impairment Charge After Tax ImpairmentChargeAfterTax	8800000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	21000000.0	usd
CY2021Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	23300000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	12700000	usd
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	16400000	usd
CY2022Q4	us-gaap	Real Estate Investments RealEstateInvestments	19100000	usd
CY2021Q4	us-gaap	Real Estate Investments RealEstateInvestments	19400000	usd
CY2022Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2021Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2022Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	58800000	usd
CY2021Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	64800000	usd
CY2022Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	90400000	usd
CY2021Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	86700000	usd
CY2022Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	204300000	usd
CY2021Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	212900000	usd
CY2022Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	150700000	usd
CY2021Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	27200000	usd
CY2022Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	6100000	usd
CY2021Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	12600000	usd
CY2022Q4	ale	Public Utilities Reserve For Interim Rate Refund PublicUtilitiesReserveForInterimRateRefund	18400000	usd
CY2021Q4	ale	Public Utilities Reserve For Interim Rate Refund PublicUtilitiesReserveForInterimRateRefund	0	usd
CY2022Q4	ale	Manufactured Gas Plant Current ManufacturedGasPlantCurrent	14700000	usd
CY2021Q4	ale	Manufactured Gas Plant Current ManufacturedGasPlantCurrent	12800000	usd
CY2022Q4	ale	Public Utilities Fuel Adjustment Clause PublicUtilitiesFuelAdjustmentClause	0	usd
CY2021Q4	ale	Public Utilities Fuel Adjustment Clause PublicUtilitiesFuelAdjustmentClause	5000000.0	usd
CY2022Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3200000	usd
CY2021Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	4800000	usd
CY2022Q4	ale	Redeemable Non Controlling Interest RedeemableNonControllingInterest	0	usd
CY2021Q4	ale	Redeemable Non Controlling Interest RedeemableNonControllingInterest	30600000	usd
CY2022Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	57900000	usd
CY2021Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	40000000.0	usd
CY2022Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	251000000.0	usd
CY2021Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	133000000.0	usd
CY2022Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	200400000	usd
CY2021Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	184500000	usd
CY2022Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	26900000	usd
CY2021Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	39500000	usd
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	9300000	usd
CY2021Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	11600000	usd
CY2022Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	32400000	usd
CY2021Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	45200000	usd
CY2022Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	269000000.0	usd
CY2021Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	280800000	usd
CY2022	us-gaap	Lessee Operating Lease Residual Value Guarantee Description LesseeOperatingLeaseResidualValueGuaranteeDescription	Our largest operating lease is for the dragline at BNI Energy which includes a termination payment at the end of the lease term if we do not exercise our purchase option.
CY2022Q4	us-gaap	Residual Value Of Leased Asset ResidualValueOfLeasedAsset	3000000	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	6300000	usd
CY2021	us-gaap	Operating Lease Cost OperatingLeaseCost	6700000	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	6300000	usd
CY2021	us-gaap	Operating Lease Payments OperatingLeasePayments	6700000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	12700000	usd
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	16400000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	12700000	usd
CY2021Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	16400000	usd
CY2022Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3200000	usd
CY2021Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	4800000	usd
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	9300000	usd
CY2021Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	11600000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	12500000	usd
CY2021Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	16400000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	3400000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	3100000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	2900000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	2900000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3800000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1200000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	17300000	usd
CY2022Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	4800000	usd
CY2022Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	12500000	usd
CY2022Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3200000	usd
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	9300000	usd
CY2022	us-gaap	Revenue Performance Obligation Description Of Payment Terms RevenuePerformanceObligationDescriptionOfPaymentTerms	Payment terms and conditions vary across our businesses. Aside from taconite-producing Large Power Customers, payment terms generally require payment to be made within 15 to 30 days from the end of the period that the service has been rendered. In the case of its taconite-producing Large Power Customers, as permitted by the MPUC, Minnesota Power requires weekly payments for electric usage based on monthly energy usage estimates.
CY2022Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	21000000	usd
CY2021Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	23300000	usd
CY2022	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2400000	usd
CY2021	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2700000	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22400000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	8700000	usd
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	14700000	usd
CY2022	ale	Morelikelythannotdefined Morelikelythannotdefined	0.50
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5004000000	usd
CY2021Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5087500000	usd
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	166600000	usd
CY2021	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	8800000	usd
CY2021	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	4500000	usd
CY2021	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	5200000	usd
CY2021	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	9800000	usd
CY2021Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	184500000	usd
CY2022	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	9500000	usd
CY2022	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	7800000	usd
CY2022	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	4400000	usd
CY2022	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	3000000.0	usd
CY2022Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	200400000	usd
CY2022Q4	us-gaap	Jointly Owned Utility Plant Gross Ownership Amount Of Plant In Service JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService	813000000.0	usd
CY2022Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Plant Accumulated Depreciation JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation	361200000	usd
CY2022Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Construction Work In Progress JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress	3300000	usd
CY2021Q4	us-gaap	Jointly Owned Utility Plant Gross Ownership Amount Of Plant In Service JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService	783700000	usd
CY2021Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Plant Accumulated Depreciation JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation	329600000	usd
CY2021Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Construction Work In Progress JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress	30100000	usd
CY2022Q4	ale	Conservation Improvement Program Goal In2 Years ConservationImprovementProgramGoalIn2Years	10900000	usd
CY2022	us-gaap	Types Of Net Regulatory Assets Earning Returns TypesOfNetRegulatoryAssetsEarningReturns	With the exception of the regulatory asset for Boswell Units 1 and 2 net plant and equipment, no other regulatory assets are currently earning a return.
CY2022Q4	us-gaap	Regulatory Assets RegulatoryAssets	25600000	usd
CY2021Q4	us-gaap	Regulatory Assets RegulatoryAssets	0	usd
CY2022Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	441000000.0	usd
CY2021Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	511800000	usd
CY2022Q4	ale	Regulated Utility Interim Rate Refund RegulatedUtilityInterimRateRefund	18400000	usd
CY2021Q4	ale	Regulated Utility Interim Rate Refund RegulatedUtilityInterimRateRefund	0	usd
CY2022Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	23400000	usd
CY2021Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	8600000	usd
CY2022Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	526100000	usd
CY2021Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	536100000	usd
CY2022Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	700000	usd
CY2022Q4	ale	Availableforsale Securities Debt Maturities After One Year Through Three Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterOneYearThroughThreeYearsFairValue	2700000	usd
CY2022Q4	ale	Availableforsale Securities Debt Maturities After Three Years Through Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterThreeYearsThroughFiveYearsFairValue	1900000	usd
CY2022Q4	ale	Availableforsale Securities Debt Maturities After Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterFiveYearsFairValue	400000	usd
CY2022Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1929100000	usd
CY2021Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1986400000	usd
CY2022Q4	us-gaap	Equity Method Investments EquityMethodInvestments	322700000	usd
CY2021Q4	us-gaap	Equity Method Investments EquityMethodInvestments	318000000	usd
CY2022Q4	us-gaap	Goodwill Goodwill	154900000	usd
CY2022	us-gaap	Property Plant And Equipment Impairment PropertyPlantAndEquipmentImpairment	The Company assesses the impairment of property, plant, and equipment whenever events or changes in circumstances indicate that the carrying amount of property, plant, and equipment assets may not be recoverable.
CY2022Q4	us-gaap	Debt Current DebtCurrent	272600000	usd
CY2021Q4	us-gaap	Debt Current DebtCurrent	214200000	usd
CY2022Q4	us-gaap	Deferred Finance Costs Current Net DeferredFinanceCostsCurrentNet	100000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1648200000	usd
CY2021Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1763200000	usd
CY2022Q4	us-gaap	Deferred Finance Costs Noncurrent Net DeferredFinanceCostsNoncurrentNet	8200000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	91900000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	94800000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	386100000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	79400000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	122500000	usd
CY2022Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1154400000	usd
CY2022Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	8300000	usd
CY2021Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	9000000.0	usd
CY2022Q4	us-gaap	Long Term Debt LongTermDebt	1920800000	usd
CY2021Q4	us-gaap	Long Term Debt LongTermDebt	1977400000	usd
CY2022Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	272600000	usd
CY2021Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	214200000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1648200000	usd
CY2021Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1763200000	usd
CY2022Q4	ale	Debt Instrument Actual Indebtedness To Total Capital Ratio DebtInstrumentActualIndebtednessToTotalCapitalRatio	0.40
CY2022Q2	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	3700000	shares
CY2022Q2	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	224000000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	189300000	usd
CY2022	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	189300000	usd
CY2022	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	55900000	shares
CY2022	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2022	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	56000000.0	shares
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2021	us-gaap	Net Income Loss NetIncomeLoss	169200000	usd
CY2021	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	169200000	usd
CY2021	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52400000	shares
CY2021	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2021	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52500000	shares
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.23
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	0	usd
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	0	usd
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.23
CY2020	us-gaap	Net Income Loss NetIncomeLoss	165400000	usd
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	165400000	usd
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51900000	shares
CY2020	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51900000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.18
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.18
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1200000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	usd
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	usd
CY2022	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	6100000	usd
CY2021	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	usd
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	0	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	7300000	usd
CY2022	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-32800000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-37200000	usd
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-51500000	usd
CY2022	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-5200000	usd
CY2021	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	10800000	usd
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	8600000	usd
CY2022	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-500000	usd
CY2021	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-500000	usd
CY2020	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-500000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-38500000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-26900000	usd
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-43400000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-31200000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-26900000	usd
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-43400000	usd
CY2022	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	100100000	usd
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$ALE
ALLETE INC Stock $ale

2023 Q1 Form 10-K Financial Statement

#000006675623000005 Filed on February 16, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE ALLETE INC Stock $ale

2023 Q1 Form 10-K Financial Statement

#000006675623000005 Filed on February 16, 2023

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE
ALLETE INC Stock $ale