$ALE
ALLETE INC Stock $ale

$ale Overview Financials Valuation SEC Filings Company Website

2024 Q1 Form 10-K Financial Statement

#000006675624000007 Filed on February 20, 2024

Income Statement

Concept	2024 Q1	2023 Q4	2023
Revenue	$403.3M	$402.7M	$1.880B
YoY Change	-28.61%	-5.43%	19.68%
Cost Of Revenue	$24.40M	$36.80M	$473.5M
YoY Change	-88.41%	-57.16%	159.03%
Gross Profit	$378.9M	$365.9M	$1.406B
YoY Change	6.91%	7.65%	1.33%
Gross Profit Margin	93.95%	90.86%	74.81%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$65.00M	$65.30M	$251.8M
YoY Change	4.33%	4.15%	3.96%
% of Gross Profit	17.15%	17.85%	17.91%
Operating Expenses	$331.6M	$322.8M	$1.225B
YoY Change	8.33%	5.46%	-2.05%
Operating Profit	$47.30M	$43.10M	$180.9M
YoY Change	-2.07%	27.89%	34.8%
Interest Expense	$20.40M	-$12.70M	$80.80M
YoY Change	5.7%	-2.31%	7.45%
% of Operating Profit	43.13%	-29.47%	44.67%
Other Income/Expense, Net	-$6.300M	$6.800M	$25.90M
YoY Change	-31.52%	54.55%	-175.95%
Pretax Income	$41.00M	$38.50M	$206.8M
YoY Change	4.86%	51.57%	106.59%
Income Tax	$4.000M	$7.500M	$27.90M
% Of Pretax Income	9.76%	19.48%	13.49%
Net Earnings	$50.70M	$51.50M	$247.1M
YoY Change	-12.89%	-0.39%	30.53%
Net Earnings / Revenue	12.57%	12.79%	13.15%
Basic Earnings Per Share	$0.88	$0.89	$4.31
Diluted Earnings Per Share	$0.88	$0.89	$4.30
COMMON SHARES
Basic Shares Outstanding	57.58M shares		57.30M shares
Diluted Shares Outstanding	57.70M shares		57.40M shares

Balance Sheet

Concept	2024 Q1	2023 Q4	2023
SHORT-TERM ASSETS
Cash & Short-Term Investments	$32.00M	$71.90M	$71.90M
YoY Change	7.02%	97.53%	97.53%
Cash & Equivalents	$32.00M	$71.90M	$71.90M
Short-Term Investments
Other Short-Term Assets	$76.30M	$83.60M	$107.4M
YoY Change	5.1%	-4.78%	22.32%
Inventory	$182.7M	$175.4M	$175.4M
Prepaid Expenses
Receivables	$142.2M	$129.0M	$105.2M
Other Receivables	$0.00	$0.00	$8.200M
Total Short-Term Assets	$433.2M	$468.1M	$468.1M
YoY Change	-23.96%	-34.81%	-34.81%
LONG-TERM ASSETS
Property, Plant & Equipment	$5.009B	$5.013B	$5.037B
YoY Change	0.6%	0.19%	0.02%
Goodwill	$154.9M	$154.9M
YoY Change	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments	$333.1M	$331.2M	$331.2M
YoY Change	2.84%	2.63%	2.63%
Other Assets	$264.8M	$262.9M	$646.2M
YoY Change	27.92%	28.68%	9.06%
Total Long-Term Assets	$6.171B	$6.188B	$6.188B
YoY Change	0.6%	0.99%	0.99%
TOTAL ASSETS
Total Short-Term Assets	$433.2M	$468.1M	$468.1M
Total Long-Term Assets	$6.171B	$6.188B	$6.188B
Total Assets	$6.605B	$6.656B	$6.656B
YoY Change	-1.49%	-2.76%	-2.76%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$84.20M	$102.2M	$102.2M
YoY Change	-0.82%	-0.78%	-0.78%
Accrued Expenses	$19.40M	$24.10M	$24.10M
YoY Change	8.38%	1.69%	1.69%
Deferred Revenue	$5.700M	$7.400M
YoY Change	-44.66%	-95.09%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$17.20M	$111.4M	$111.8M
YoY Change	-90.25%	-59.13%	-58.99%
Total Short-Term Liabilities	$260.8M	$377.6M	$377.6M
YoY Change	-43.84%	-47.28%	-47.28%
LONG-TERM LIABILITIES
Long-Term Debt	$1.772B	$1.680B	$1.682B
YoY Change	0.96%	1.92%	2.02%
Other Long-Term Liabilities	$268.0M	$264.3M	$998.0M
YoY Change	-0.89%	-1.75%	2.38%
Total Long-Term Liabilities	$2.040B	$1.944B	$2.680B
YoY Change	0.72%	1.41%	2.15%
TOTAL LIABILITIES
Total Short-Term Liabilities	$260.8M	$377.6M	$377.6M
Total Long-Term Liabilities	$2.040B	$1.944B	$2.680B
Total Liabilities	$3.196B	$3.249B	$3.847B
YoY Change	-4.52%	-7.09%	-7.39%
SHAREHOLDERS EQUITY
Retained Earnings	$1.037B	$1.026B
YoY Change	8.63%	9.8%
Common Stock	$1.807B	$1.804B
YoY Change	1.22%	1.25%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.823B	$2.810B	$2.810B
YoY Change
Total Liabilities & Shareholders Equity	$6.605B	$6.656B	$6.656B
YoY Change	-1.49%	-2.76%	-2.76%

Cashflow Statement

Concept	2024 Q1	2023 Q4	2023
OPERATING ACTIVITIES
Net Income	$50.70M	$51.50M	$247.1M
YoY Change	-12.89%	-0.39%	30.53%
Depreciation, Depletion And Amortization	$65.00M	$65.30M	$251.8M
YoY Change	4.33%	4.15%	3.96%
Cash From Operating Activities	$60.10M	$65.30M	$585.3M
YoY Change	-34.96%	-53.39%	164.48%
INVESTING ACTIVITIES
Capital Expenditures	$60.60M	$87.10M	$271.2M
YoY Change	-13.43%	27.15%	22.99%
Acquisitions			$0.00
YoY Change			-100.0%
Other Investing Activities	-$1.500M	$4.100M	$4.000M
YoY Change	-138.46%	-193.18%	66.67%
Cash From Investing Activities	-$60.80M	-$83.00M	-$283.6M
YoY Change	-18.61%	13.85%	-26.15%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$14.90M
YoY Change			-93.99%
Debt Paid & Issued, Net	$158.0M		$566.7M
YoY Change	-30.64%		-35.38%
Cash From Financing Activities	-$38.40M	-34.10M	-$262.5M
YoY Change	109.84%	-54.89%	-269.14%
NET CHANGE
Cash From Operating Activities	$60.10M	65.30M	$585.3M
Cash From Investing Activities	-$60.80M	-83.00M	-$283.6M
Cash From Financing Activities	-$38.40M	-34.10M	-$262.5M
Net Change In Cash	-$39.10M	-51.80M	$39.20M
YoY Change	6416.67%	516.67%	-622.67%
FREE CASH FLOW
Cash From Operating Activities	$60.10M	$65.30M	$585.3M
Capital Expenditures	$60.60M	$87.10M	$271.2M
Free Cash Flow	-$500.0K	-$21.80M	$314.1M
YoY Change	-102.23%	-130.45%	39162.5%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.30
CY2022	us-gaap	Profit Loss ProfitLoss	131300000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-68200000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	251000000.0	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	188700000	usd
CY2021	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	9900000	usd
CY2022	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-38500000	usd
CY2023	us-gaap	Share Based Compensation ShareBasedCompensation	7300000	usd
CY2023	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1300000	usd
CY2023	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-3600000	usd
CY2022	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-600000	usd
CY2021	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	145100000	usd
CY2021	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	800000	usd
CY2023	dei	Entity Central Index Key EntityCentralIndexKey	0000066756
CY2023Q2	dei	Entity Public Float EntityPublicFloat	3320941939	usd
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	57578222	shares
CY2023	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2023
CY2023	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2023	dei	Amendment Flag AmendmentFlag	false
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset Statement Of Financial Position Extensible List OperatingLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2023Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2022Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherAssetsNoncurrent
CY2023Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2022Q4	us-gaap	Operating Lease Liability Current Statement Of Financial Position Extensible List OperatingLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2023Q4	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2022Q4	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesCurrent
CY2023Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent Statement Of Financial Position Extensible List OperatingLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2022Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2023Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	http://fasb.org/us-gaap/2023#OtherLiabilitiesNoncurrent
CY2023	dei	Document Annual Report DocumentAnnualReport	true
CY2023	dei	Document Period End Date DocumentPeriodEndDate	2023-12-31
CY2023	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2023	dei	Document Transition Report DocumentTransitionReport	false
CY2023	dei	Entity File Number EntityFileNumber	1-3548
CY2023	dei	Entity Registrant Name EntityRegistrantName	ALLETE, Inc.
CY2023	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MN
CY2023	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	41-0418150
CY2023	dei	Entity Address Address Line1 EntityAddressAddressLine1	30 West Superior Street
CY2023	dei	Entity Address City Or Town EntityAddressCityOrTown	Duluth
CY2023	dei	Entity Address State Or Province EntityAddressStateOrProvince	MN
CY2023	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	55802-2093
CY2023	dei	City Area Code CityAreaCode	218
CY2023	dei	Local Phone Number LocalPhoneNumber	279-5000
CY2023	dei	Security12b Title Security12bTitle	Common Stock, without par value
CY2023	dei	Trading Symbol TradingSymbol	ALE
CY2023	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2023	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2023	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2023	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2023	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2023	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2023	dei	Entity Small Business EntitySmallBusiness	false
CY2023	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2023	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2023	dei	Document Fin Stmt Error Correction Flag DocumentFinStmtErrorCorrectionFlag	false
CY2023	dei	Entity Shell Company EntityShellCompany	false
CY2023Q2	dei	Entity Public Float EntityPublicFloat	3320941939	usd
CY2024Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	57578222	shares
CY2023Q4	ecd	Non Rule10b51 Arr Adopted Flag NonRule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Rule10b51 Arr Adopted Flag Rule10b51ArrAdoptedFlag	false
CY2023Q4	ecd	Non Rule10b51 Arr Trmntd Flag NonRule10b51ArrTrmntdFlag	false
CY2023Q4	ecd	Rule10b51 Arr Trmntd Flag Rule10b51ArrTrmntdFlag	false
CY2023	dei	Auditor Name AuditorName	PricewaterhouseCoopers LLP
CY2023	dei	Auditor Location AuditorLocation	Minneapolis, MN
CY2023	dei	Auditor Firm AuditorFirmId	238
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	71900000	usd
CY2022Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	36400000	usd
CY2023Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1600000	usd
CY2022Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1600000	usd
CY2023Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	137200000	usd
CY2022Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	137900000	usd
CY2023Q4	us-gaap	Inventory Net InventoryNet	175400000	usd
CY2022Q4	us-gaap	Inventory Net InventoryNet	455900000	usd
CY2023Q4	us-gaap	Other Assets Current OtherAssetsCurrent	83600000	usd
CY2022Q4	us-gaap	Other Assets Current OtherAssetsCurrent	87800000	usd
CY2023Q4	us-gaap	Assets Current AssetsCurrent	468100000	usd
CY2022Q4	us-gaap	Assets Current AssetsCurrent	718000000.0	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5013400000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5004000000	usd
CY2023Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	425400000	usd
CY2022Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	441000000.0	usd
CY2023Q4	us-gaap	Equity Method Investments EquityMethodInvestments	331200000	usd
CY2022Q4	us-gaap	Equity Method Investments EquityMethodInvestments	322700000	usd
CY2023Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	155400000	usd
CY2022Q4	us-gaap	Intangible Assets Net Including Goodwill IntangibleAssetsNetIncludingGoodwill	155600000	usd
CY2023Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	262900000	usd
CY2022Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	204300000	usd
CY2021	us-gaap	Regulated Operating Revenue RegulatedOperatingRevenue	1227900000	usd
CY2023	us-gaap	Unregulated Operating Revenue UnregulatedOperatingRevenue	636400000	usd
CY2022	us-gaap	Unregulated Operating Revenue UnregulatedOperatingRevenue	303800000	usd
CY2023Q4	us-gaap	Assets Assets	6656400000	usd
CY2022Q4	us-gaap	Assets Assets	6845600000	usd
CY2023Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	102200000	usd
CY2022Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	103000000.0	usd
CY2023Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	51000000.0	usd
CY2022Q4	us-gaap	Taxes Payable Current TaxesPayableCurrent	69100000	usd
CY2023Q4	us-gaap	Interest Payable Current InterestPayableCurrent	21100000	usd
CY2022Q4	us-gaap	Interest Payable Current InterestPayableCurrent	20500000	usd
CY2023Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	111400000	usd
CY2022Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	272600000	usd
CY2023Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	91900000	usd
CY2022Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	251000000.0	usd
CY2023Q4	us-gaap	Liabilities Current LiabilitiesCurrent	377600000	usd
CY2022Q4	us-gaap	Liabilities Current LiabilitiesCurrent	716200000	usd
CY2023Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1679900000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1648200000	usd
CY2023Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	192700000	usd
CY2022Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	158100000	usd
CY2023Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	574000000.0	usd
CY2022Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	526100000	usd
CY2023Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	160800000	usd
CY2022Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	179700000	usd
CY2023Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	264300000	usd
CY2022Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	269000000.0	usd
CY2023Q4	us-gaap	Liabilities Liabilities	3249300000	usd
CY2022Q4	us-gaap	Liabilities Liabilities	3497300000	usd
CY2023Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2022Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		usd
CY2023Q4	us-gaap	Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests	500000	usd
CY2022Q4	us-gaap	Temporary Equity Carrying Amount Including Portion Attributable To Noncontrolling Interests TemporaryEquityCarryingAmountIncludingPortionAttributableToNoncontrollingInterests	0	usd
CY2022Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	80000000.0	shares
CY2023Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	80000000.0	shares
CY2023Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	57600000	shares
CY2023Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	57600000	shares
CY2022Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	57200000	shares
CY2022Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	57200000	shares
CY2023Q4	us-gaap	Common Stock Value CommonStockValue	1803700000	usd
CY2022Q4	us-gaap	Common Stock Value CommonStockValue	1781500000	usd
CY2023Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-20500000	usd
CY2022Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-24400000	usd
CY2023Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	1026400000	usd
CY2022Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	934800000	usd
CY2023Q4	us-gaap	Stockholders Equity StockholdersEquity	2809600000	usd
CY2022Q4	us-gaap	Stockholders Equity StockholdersEquity	2691900000	usd
CY2023Q4	us-gaap	Minority Interest MinorityInterest	597000000.0	usd
CY2022Q4	us-gaap	Minority Interest MinorityInterest	656400000	usd
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3406600000	usd
CY2022Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3348300000	usd
CY2023Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	6656400000	usd
CY2022Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	6845600000	usd
CY2023	us-gaap	Regulated Operating Revenue RegulatedOperatingRevenue	1238300000	usd
CY2022	us-gaap	Regulated Operating Revenue RegulatedOperatingRevenue	1259300000	usd
CY2021	us-gaap	Unregulated Operating Revenue UnregulatedOperatingRevenue	179900000	usd
CY2023	us-gaap	Revenue Not From Contract With Customer Other RevenueNotFromContractWithCustomerOther	5100000	usd
CY2022	us-gaap	Revenue Not From Contract With Customer Other RevenueNotFromContractWithCustomerOther	7600000	usd
CY2021	us-gaap	Revenue Not From Contract With Customer Other RevenueNotFromContractWithCustomerOther	11400000	usd
CY2023	us-gaap	Revenues Revenues	1879800000	usd
CY2022	us-gaap	Revenues Revenues	1570700000	usd
CY2021	us-gaap	Revenues Revenues	1419200000	usd
CY2023	ale	Fuel Purchased Powerand Gas Utility FuelPurchasedPowerandGasUtility	482900000	usd
CY2022	ale	Fuel Purchased Powerand Gas Utility FuelPurchasedPowerandGasUtility	545500000	usd
CY2021	ale	Fuel Purchased Powerand Gas Utility FuelPurchasedPowerandGasUtility	562400000	usd
CY2023	ale	Transmission Services Utility TransmissionServicesUtility	88200000	usd
CY2022	ale	Transmission Services Utility TransmissionServicesUtility	76700000	usd
CY2021	ale	Transmission Services Utility TransmissionServicesUtility	75300000	usd
CY2023	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	473500000	usd
CY2022	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	182800000	usd
CY2021	us-gaap	Cost Of Goods And Services Sold CostOfGoodsAndServicesSold	68800000	usd
CY2023	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	345300000	usd
CY2022	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	318900000	usd
CY2021	us-gaap	Other General And Administrative Expense OtherGeneralAndAdministrativeExpense	259200000	usd
CY2023	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	251800000	usd
CY2022	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	242200000	usd
CY2021	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	231700000	usd
CY2023	us-gaap	Taxes Other TaxesOther	57200000	usd
CY2022	us-gaap	Taxes Other TaxesOther	70400000	usd
CY2021	us-gaap	Taxes Other TaxesOther	70500000	usd
CY2023	us-gaap	Costs And Expenses CostsAndExpenses	1698900000	usd
CY2022	us-gaap	Costs And Expenses CostsAndExpenses	1436500000	usd
CY2021	us-gaap	Costs And Expenses CostsAndExpenses	1267900000	usd
CY2023	us-gaap	Operating Income Loss OperatingIncomeLoss	180900000	usd
CY2022	us-gaap	Operating Income Loss OperatingIncomeLoss	134200000	usd
CY2021	us-gaap	Operating Income Loss OperatingIncomeLoss	151300000	usd
CY2023	us-gaap	Interest Expense InterestExpense	80800000	usd
CY2022	us-gaap	Interest Expense InterestExpense	75200000	usd
CY2021	us-gaap	Interest Expense InterestExpense	69100000	usd
CY2023	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	21700000	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
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	85000000.0	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22400000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	8700000	usd
CY2023	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	25900000	usd
CY2022	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-34100000	usd
CY2021	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-40400000	usd
CY2023	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	206800000	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
CY2023	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	27900000	usd
CY2022	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-31200000	usd
CY2021	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-26900000	usd
CY2023	us-gaap	Profit Loss ProfitLoss	178900000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	131300000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	137800000	usd
CY2023	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-68200000	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
CY2023	us-gaap	Net Income Loss NetIncomeLoss	247100000	usd
CY2022	us-gaap	Net Income Loss NetIncomeLoss	189300000	usd
CY2021	us-gaap	Net Income Loss NetIncomeLoss	169200000	usd
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	57300000	shares
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
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	57400000	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
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.31
CY2022	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.38
CY2021	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.23
CY2022	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2021	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.23
CY2021	us-gaap	Profit Loss ProfitLoss	137800000	usd
CY2023	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodTax	100000	usd
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
CY2023	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3900000	usd
CY2023	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	182800000	usd
CY2022	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	130700000	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
CY2021	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	176500000	usd
CY2023	us-gaap	Profit Loss ProfitLoss	178900000	usd
CY2022	us-gaap	Profit Loss ProfitLoss	131300000	usd
CY2021	us-gaap	Profit Loss ProfitLoss	137800000	usd
CY2023	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	3600000	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
CY2023	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	-1000000.0	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
CY2023	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	0	usd
CY2022	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	-1200000	usd
CY2023	us-gaap	Depreciation Depreciation	251700000	usd
CY2022	us-gaap	Depreciation Depreciation	242000000.0	usd
CY2023	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	5200000	usd
CY2022	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	7600000	usd
CY2021	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	11400000	usd
CY2021	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-26900000	usd
CY2022	us-gaap	Share Based Compensation ShareBasedCompensation	4900000	usd
CY2021	us-gaap	Share Based Compensation ShareBasedCompensation	5900000	usd
CY2023	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-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
CY2022	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1900000	usd
CY2021	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1200000	usd
CY2023	ale	Changes In Fuel Adjustment Clause Regulatory Asset And Liability ChangesInFuelAdjustmentClauseRegulatoryAssetAndLiability	44000000.0	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
CY2023	ale	Provision Payments For Interim Rate Refund ProvisionPaymentsForInterimRateRefund	-18400000	usd
CY2022	ale	Provision Payments For Interim Rate Refund ProvisionPaymentsForInterimRateRefund	18400000	usd
CY2021	ale	Provision Payments For Interim Rate Refund ProvisionPaymentsForInterimRateRefund	0	usd
CY2023	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-1800000	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
CY2023	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-277100000	usd
CY2022	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	256100000	usd
CY2021	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	23500000	usd
CY2023	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	7900000	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
CY2023	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-4000000.0	usd
CY2022	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-1300000	usd
CY2021	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	15000000.0	usd
CY2023	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-157600000	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
CY2023	us-gaap	Pension Contributions PensionContributions	17300000	usd
CY2022	us-gaap	Pension Contributions PensionContributions	0	usd
CY2021	us-gaap	Pension Contributions PensionContributions	10300000	usd
CY2023	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-15600000	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
CY2023	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	2000000.0	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
CY2023	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	585300000	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
CY2023	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	1000000.0	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
CY2023	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	1200000	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
CY2023	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	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
CY2023	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	8200000	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
CY2023	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	271200000	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
CY2023	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	4000000.0	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
CY2023	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-283600000	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
CY2023	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	14900000	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
CY2023	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	usd
CY2022	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	8100000	usd
CY2021	us-gaap	Payments Of Stock Issuance Costs PaymentsOfStockIssuanceCosts	0	usd
CY2023	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	437000000.0	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
CY2023	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	566700000	usd
CY2022	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	877000000.0	usd
CY2021	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	552900000	usd
CY2023	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	17800000	usd
CY2022	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	155700000	usd
CY2021	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	90900000	usd
CY2023	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	8500000	usd
CY2022	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	1700000	usd
CY2021	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	3100000	usd
CY2023	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	155500000	usd
CY2022	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	145900000	usd
CY2021	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	131900000	usd
CY2023	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1500000	usd
CY2022	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1200000	usd
CY2021	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1700000	usd
CY2023	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-262500000	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
CY2023	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	39200000	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
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
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	79400000	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
CY2023Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	3406600000	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
CY2022Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	0	usd
CY2021Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	0	usd
CY2020Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	0	usd
CY2023	us-gaap	Temporary Equity Interest In Subsidiary Earnings TemporaryEquityInterestInSubsidiaryEarnings	7900000	usd
CY2022	us-gaap	Temporary Equity Interest In Subsidiary Earnings TemporaryEquityInterestInSubsidiaryEarnings	0	usd
CY2021	us-gaap	Temporary Equity Interest In Subsidiary Earnings TemporaryEquityInterestInSubsidiaryEarnings	0	usd
CY2023	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	-7400000	usd
CY2022	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	0	usd
CY2021	us-gaap	Temporary Equity Net Income TemporaryEquityNetIncome	0	usd
CY2023Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	500000	usd
CY2022Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	0	usd
CY2021Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	0	usd
CY2023	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.71
CY2022	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.60
CY2021	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.52
CY2023	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	segment
CY2023Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	71900000	usd
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
CY2023Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	5100000	usd
CY2022Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	1500000	usd
CY2021Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	300000	usd
CY2023Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2400000	usd
CY2022Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2021Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2023Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	79400000	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
CY2023	us-gaap	Interest Paid Net InterestPaidNet	80500000	usd
CY2022	us-gaap	Interest Paid Net InterestPaidNet	72800000	usd
CY2021	us-gaap	Interest Paid Net InterestPaidNet	66800000	usd
CY2023	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	19500000	usd
CY2022	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	6000000.0	usd
CY2021	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	0	usd
CY2023	ale	Increase Decrease In Accounts Payable For Capital Additions To Property Plant And Equipment IncreaseDecreaseInAccountsPayableForCapitalAdditionsToPropertyPlantAndEquipment	2200000	usd
CY2022	ale	Increase Decrease In Accounts Payable For Capital Additions To Property Plant And Equipment IncreaseDecreaseInAccountsPayableForCapitalAdditionsToPropertyPlantAndEquipment	-9600000	usd
CY2021	ale	Increase Decrease In Accounts Payable For Capital Additions To Property Plant And Equipment IncreaseDecreaseInAccountsPayableForCapitalAdditionsToPropertyPlantAndEquipment	-14000000.0	usd
CY2023	ale	Reclassification Of Property Plant And Equipment To Inventory ReclassificationOfPropertyPlantAndEquipmentToInventory	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
CY2023	ale	Non Cash Reclassification Of Redeemable Non Controlling Interest To Current Liabilities NonCashReclassificationOfRedeemableNonControllingInterestToCurrentLiabilities	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
CY2023	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	5800000	usd
CY2022	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	11800000	usd
CY2021	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	16900000	usd
CY2023	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	3600000	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
CY2023Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	106800000	usd
CY2022Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	107100000	usd
CY2023Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	23800000	usd
CY2022Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	29200000	usd
CY2023Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1600000	usd
CY2022Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1600000	usd
CY2023Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	129000000.0	usd
CY2022Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	134700000	usd
CY2023Q4	us-gaap	Nontrade Receivables Current NontradeReceivablesCurrent	8200000	usd
CY2022Q4	us-gaap	Nontrade Receivables Current NontradeReceivablesCurrent	3200000	usd
CY2023Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	137200000	usd
CY2022Q4	us-gaap	Accounts And Other Receivables Net Current AccountsAndOtherReceivablesNetCurrent	137900000	usd
CY2023Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	27200000	usd
CY2022Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	33400000	usd
CY2023Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	115700000	usd
CY2022Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	75100000	usd
CY2023Q4	us-gaap	Other Inventory OtherInventory	32500000	usd
CY2022Q4	us-gaap	Other Inventory OtherInventory	347400000	usd
CY2023Q4	us-gaap	Inventory Net InventoryNet	175400000	usd
CY2022Q4	us-gaap	Inventory Net InventoryNet	455900000	usd
CY2022	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2021	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2023	us-gaap	Impairment Of Long Lived Assets Held For Use ImpairmentOfLongLivedAssetsHeldForUse	0	usd
CY2023Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	18500000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	21000000.0	usd
CY2023Q4	us-gaap	Real Estate Investments RealEstateInvestments	10800000	usd
CY2022Q4	us-gaap	Real Estate Investments RealEstateInvestments	19100000	usd
CY2023Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2400000	usd
CY2022Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	usd
CY2023Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	106300000	usd
CY2022Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	58800000	usd
CY2023Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	124900000	usd
CY2022Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	103100000	usd
CY2023Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	262900000	usd
CY2022Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	204300000	usd
CY2023Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	7400000	usd
CY2022Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	150700000	usd
CY2023Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	6000000.0	usd
CY2022Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	6100000	usd
CY2023Q4	ale	Public Utilities Reserve For Interim Rates PublicUtilitiesReserveForInterimRates	0	usd
CY2022Q4	ale	Public Utilities Reserve For Interim Rates PublicUtilitiesReserveForInterimRates	18400000	usd
CY2023Q4	ale	Manufactured Gas Plant Current ManufacturedGasPlantCurrent	800000	usd
CY2022Q4	ale	Manufactured Gas Plant Current ManufacturedGasPlantCurrent	14700000	usd
CY2023Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	77700000	usd
CY2022Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	61100000	usd
CY2023Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	91900000	usd
CY2022Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	251000000.0	usd
CY2023Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	202900000	usd
CY2022Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	200400000	usd
CY2023Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	20900000	usd
CY2022Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	26900000	usd
CY2023Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	40500000	usd
CY2022Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	41700000	usd
CY2023Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	264300000	usd
CY2022Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	269000000.0	usd
CY2023Q4	us-gaap	Residual Value Of Leased Asset ResidualValueOfLeasedAsset	3000000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	5000000.0	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	6300000	usd
CY2023	ale	Finance Lease Cost FinanceLeaseCost	100000	usd
CY2022	ale	Finance Lease Cost FinanceLeaseCost	0	usd
CY2023	us-gaap	Operating Lease Payments OperatingLeasePayments	5000000.0	usd
CY2022	us-gaap	Operating Lease Payments OperatingLeasePayments	6300000	usd
CY2023	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	200000	usd
CY2022	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	0	usd
CY2023Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	10700000	usd
CY2022Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	12700000	usd
CY2023Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	2100000	usd
CY2022Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	0	usd
CY2023Q4	ale	Lease Right Of Use Asset LeaseRightOfUseAsset	12800000	usd
CY2022Q4	ale	Lease Right Of Use Asset LeaseRightOfUseAsset	12700000	usd
CY2023Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3000000.0	usd
CY2022Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3200000	usd
CY2023Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	400000	usd
CY2022Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	0	usd
CY2023Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	7700000	usd
CY2022Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	9300000	usd
CY2023Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	1600000	usd
CY2022Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	0	usd
CY2023Q4	ale	Lease Liability LeaseLiability	12700000	usd
CY2022Q4	ale	Lease Liability LeaseLiability	12500000	usd
CY2023	us-gaap	Operating Lease Cost OperatingLeaseCost	5000000.0	usd
CY2022	us-gaap	Operating Lease Cost OperatingLeaseCost	6300000	usd
CY2023	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	100000	usd
CY2022	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	0	usd
CY2023	us-gaap	Lease Cost LeaseCost	5100000	usd
CY2022	us-gaap	Lease Cost LeaseCost	6300000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	3200000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	400000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	3200000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	400000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	3200000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	400000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4100000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	500000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	200000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	600000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1200000	usd
CY2023Q4	ale	Finance Lease Liability To Be Paid Due After Year Five FinanceLeaseLiabilityToBePaidDueAfterYearFive	0	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	15100000	usd
CY2023Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	2300000	usd
CY2023Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	4400000	usd
CY2023Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	300000	usd
CY2023Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	10700000	usd
CY2023Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	2000000.0	usd
CY2023Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	3000000.0	usd
CY2023Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	400000	usd
CY2023Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	7700000	usd
CY2023Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	1600000	usd
CY2023Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	18500000	usd
CY2022Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	21000000	usd
CY2023	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2400000	usd
CY2022	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2400000	usd
CY2023	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	10300000	usd
CY2023	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	10200000	usd
CY2023	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	2400000	usd
CY2023Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	202900000	usd
CY2023	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	85000000.0	usd
CY2022	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	22400000	usd
CY2021	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	8700000	usd
CY2023Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5013400000	usd
CY2022Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	5004000000	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
CY2023Q4	us-gaap	Jointly Owned Utility Plant Gross Ownership Amount Of Plant In Service JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService	826900000	usd
CY2023Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Plant Accumulated Depreciation JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation	393400000	usd
CY2023Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Construction Work In Progress JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress	2800000	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
CY2023Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	9300000	usd
CY2022Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	25600000	usd
CY2023Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	425400000	usd
CY2022Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	441000000.0	usd
CY2023Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	3900000	usd
CY2022Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	23400000	usd
CY2023Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	574000000.0	usd
CY2022Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	526100000	usd
CY2023Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1300000	usd
CY2023Q4	ale	Availableforsale Securities Debt Maturities After One Year Through Three Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterOneYearThroughThreeYearsFairValue	3200000	usd
CY2023Q4	ale	Availableforsale Securities Debt Maturities After Three Years Through Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterThreeYearsThroughFiveYearsFairValue	1000000	usd
CY2023Q4	ale	Availableforsale Securities Debt Maturities After Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterFiveYearsFairValue	500000	usd
CY2023Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1799400000	usd
CY2022Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1929100000	usd
CY2023Q4	us-gaap	Equity Method Investments EquityMethodInvestments	331200000	usd
CY2022Q4	us-gaap	Equity Method Investments EquityMethodInvestments	322700000	usd
CY2023Q4	us-gaap	Goodwill Goodwill	154900000	usd
CY2023	us-gaap	Property Plant And Equipment Impairment PropertyPlantAndEquipmentImpairment	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Property, Plant and Equipment. </span>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.
CY2023Q4	us-gaap	Debt Current DebtCurrent	111400000	usd
CY2022Q4	us-gaap	Debt Current DebtCurrent	272600000	usd
CY2023Q4	us-gaap	Deferred Finance Costs Current Net DeferredFinanceCostsCurrentNet	100000	usd
CY2023Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1679900000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1648200000	usd
CY2023Q4	us-gaap	Deferred Finance Costs Noncurrent Net DeferredFinanceCostsNoncurrentNet	8000000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	111400000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	244700000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	80200000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	162500000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	55800000	usd
CY2023Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1144800000	usd
CY2023Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	8100000	usd
CY2022Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	8300000	usd
CY2023Q4	us-gaap	Long Term Debt LongTermDebt	1791300000	usd
CY2022Q4	us-gaap	Long Term Debt LongTermDebt	1920800000	usd
CY2023Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	111400000	usd
CY2022Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	272600000	usd
CY2023Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1679900000	usd
CY2022Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1648200000	usd
CY2023Q4	ale	Debt Instrument Actual Indebtedness To Total Capital Ratio DebtInstrumentActualIndebtednessToTotalCapitalRatio	0.36
CY2023Q3	ale	Proceeds From Legal Settlements Gross ProceedsFromLegalSettlementsGross	68300000	usd
CY2023Q3	ale	Litigation Settlement Amount Awarded From Other Party Prejudgment Interest LitigationSettlementAmountAwardedFromOtherPartyPrejudgmentInterest	5100000	usd
CY2023Q3	ale	Litigation Settlement Amount Awarded From Other Party Arbitration Costs Recovery LitigationSettlementAmountAwardedFromOtherPartyArbitrationCostsRecovery	3600000	usd
CY2023Q3	ale	Litigation Settlement Amount Awarded From Other Party Pre Tax Gain LitigationSettlementAmountAwardedFromOtherPartyPreTaxGain	58400000	usd
CY2023Q3	us-gaap	Proceeds From Legal Settlements ProceedsFromLegalSettlements	60000000	usd
CY2021	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	51000000	usd
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	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-32800000	usd
CY2021	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-37200000	usd
CY2023	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	24000000.0	usd
CY2023	us-gaap	Net Income Loss NetIncomeLoss	247100000	usd
CY2023	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	247100000	usd
CY2023	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	57300000	shares
CY2023	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2023	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	57400000	shares
CY2023	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.31
CY2023	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.30
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	Earnings Per Share Diluted EarningsPerShareDiluted	3.23
CY2023	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	9400000	usd
CY2022	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	1200000	usd
CY2021	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	usd
CY2023	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	900000	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
CY2023	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	10300000	usd
CY2022	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	7300000	usd
CY2021	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	0	usd
CY2023	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-6000000.0	usd
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$ALE
ALLETE INC Stock $ale

2024 Q1 Form 10-K Financial Statement

#000006675624000007 Filed on February 20, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE ALLETE INC Stock $ale

2024 Q1 Form 10-K Financial Statement

#000006675624000007 Filed on February 20, 2024

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE
ALLETE INC Stock $ale