$ALE
ALLETE INC Stock $ale

$ale Overview Financials Valuation SEC Filings Company Website

2021 Q3 Form 10-Q Financial Statement

#000006675621000081 Filed on November 04, 2021

Income Statement

Concept	2021 Q3	2020 Q4	2020 Q3
Revenue	$345.4M	$320.4M	$293.9M
YoY Change	17.52%	5.19%	1.94%
Cost Of Revenue	$15.20M	$18.10M	$15.40M
YoY Change	-1.3%	-3.72%	4.76%
Gross Profit	$330.2M	$302.3M	$278.5M
YoY Change	18.56%	5.77%	1.79%
Gross Profit Margin	95.6%	94.35%	94.76%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$57.50M	$58.30M	$53.40M
YoY Change	7.68%	9.18%	7.88%
% of Gross Profit	17.41%	19.29%	19.17%
Operating Expenses	$299.1M	$265.9M	$236.9M
YoY Change	26.26%	12.67%	307.75%
Operating Profit	$31.10M	$36.40M	$41.60M
YoY Change	-25.24%	-26.91%	12.43%
Interest Expense	$17.30M	-$11.10M	$16.30M
YoY Change	6.13%	15.63%	1.24%
% of Operating Profit	55.63%	-30.49%	39.18%
Other Income/Expense, Net	-$11.90M	$4.500M	-$8.300M
YoY Change	43.37%	9.76%	1.22%
Pretax Income	$19.20M	$29.70M	$33.30M
YoY Change	-42.34%	-37.21%	15.63%
Income Tax	-$4.900M	-$11.70M	-$5.500M
% Of Pretax Income	-25.52%	-39.39%	-16.52%
Net Earnings	$27.60M	$47.10M	$40.70M
YoY Change	-32.19%	-5.23%	30.45%
Net Earnings / Revenue	7.99%	14.7%	13.85%
Basic Earnings Per Share	$0.53	$0.91	$0.78
Diluted Earnings Per Share	$0.53	$0.90	$0.78
COMMON SHARES
Basic Shares Outstanding	52.40M shares		51.90M shares
Diluted Shares Outstanding	52.50M shares		52.00M shares

Balance Sheet

Concept	2021 Q3	2020 Q4	2020 Q3
SHORT-TERM ASSETS
Cash & Short-Term Investments	$59.00M	$44.30M	$79.00M
YoY Change	-25.32%	-36.08%	-21.24%
Cash & Equivalents	$59.00M	$44.30M	$79.00M
Short-Term Investments
Other Short-Term Assets	$19.90M	$24.50M	$19.30M
YoY Change	3.11%	-20.97%	-26.05%
Inventory	$89.60M	$74.20M	$74.80M
Prepaid Expenses
Receivables	$110.2M	$111.9M	$92.00M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$278.7M	$254.9M	$265.1M
YoY Change	5.13%	-5.42%	-10.47%
LONG-TERM ASSETS
Property, Plant & Equipment	$5.053B	$4.841B	$4.698B
YoY Change	7.57%	10.6%	11.56%
Goodwill
YoY Change
Intangibles
YoY Change
Long-Term Investments	$317.8M	$301.2M	$291.8M
YoY Change	8.91%	52.43%	59.19%
Other Assets	$179.7M	$206.8M	$196.2M
YoY Change	-8.41%	-5.22%	2.4%
Total Long-Term Assets	$6.054B	$5.830B	$5.613B
YoY Change	7.84%	11.82%	12.73%
TOTAL ASSETS
Total Short-Term Assets	$278.7M	$254.9M	$265.1M
Total Long-Term Assets	$6.054B	$5.830B	$5.613B
Total Assets	$6.332B	$6.085B	$5.879B
YoY Change	7.72%	10.98%	11.42%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$101.9M	$110.0M	$79.00M
YoY Change	28.99%	-33.41%	-44.95%
Accrued Expenses	$20.30M	$25.70M	$22.10M
YoY Change	-8.14%	2.8%	0.0%
Deferred Revenue	$27.50M	$7.400M
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$377.4M	$203.7M	$404.5M
YoY Change	-6.7%	-4.32%	90.17%
Total Short-Term Liabilities	$646.0M	$459.6M	$630.0M
YoY Change	2.54%	-9.42%	30.35%
LONG-TERM LIABILITIES
Long-Term Debt	$1.649B	$1.593B	$1.608B
YoY Change	2.57%	13.73%	14.46%
Other Long-Term Liabilities	$278.1M	$285.3M	$285.5M
YoY Change	-2.59%	-2.63%	-2.59%
Total Long-Term Liabilities	$1.928B	$1.879B	$1.894B
YoY Change	1.8%	10.9%	11.51%
TOTAL LIABILITIES
Total Short-Term Liabilities	$646.0M	$459.6M	$630.0M
Total Long-Term Liabilities	$1.928B	$1.879B	$1.894B
Total Liabilities	$3.478B	$3.284B	$3.433B
YoY Change	1.31%	4.36%	11.89%
SHAREHOLDERS EQUITY
Retained Earnings	$873.4M	$864.8M	$849.9M
YoY Change	2.77%	5.62%	6.3%
Common Stock	$1.497B	$1.461B	$1.454B
YoY Change	2.91%	1.68%	1.33%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.340B	$2.295B	$2.281B
YoY Change
Total Liabilities & Shareholders Equity	$6.332B	$6.085B	$5.879B
YoY Change	7.72%	10.98%	11.42%

Cashflow Statement

Concept	2021 Q3	2020 Q4	2020 Q3
OPERATING ACTIVITIES
Net Income	$27.60M	$47.10M	$40.70M
YoY Change	-32.19%	-5.23%	30.45%
Depreciation, Depletion And Amortization	$57.50M	$58.30M	$53.40M
YoY Change	7.68%	9.18%	7.88%
Cash From Operating Activities	$103.5M	$55.90M	$99.40M
YoY Change	4.12%	-23.53%	22.41%
INVESTING ACTIVITIES
Capital Expenditures	-$90.90M	-$177.0M	-$120.9M
YoY Change	-24.81%	0.68%	-34.75%
Acquisitions
YoY Change
Other Investing Activities	-$500.0K	-$2.600M	-$24.90M
YoY Change	-97.99%	-72.63%	20.29%
Cash From Investing Activities	-$91.40M	-$179.6M	-$145.8M
YoY Change	-37.31%	-3.08%	-29.22%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-14.00M	103.8M	94.10M
YoY Change	-114.88%	49.35%	76.22%
NET CHANGE
Cash From Operating Activities	103.5M	55.90M	99.40M
Cash From Investing Activities	-91.40M	-179.6M	-145.8M
Cash From Financing Activities	-14.00M	103.8M	94.10M
Net Change In Cash	-1.900M	-19.90M	47.70M
YoY Change	-103.98%	-53.4%	-166.81%
FREE CASH FLOW
Cash From Operating Activities	$103.5M	$55.90M	$99.40M
Capital Expenditures	-$90.90M	-$177.0M	-$120.9M
Free Cash Flow	$194.4M	$232.9M	$220.3M
YoY Change	-11.76%	-6.43%	-17.34%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
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	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	Q3
	dei	Amendment Flag AmendmentFlag	false
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CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	52100000	shares
CY2021Q3	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	52600000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	52100000	shares
CY2021Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-100000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-100000	USD
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	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansTax	-200000	USD
	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	2	Segments
	dei	Document Type DocumentType	10-Q
	dei	Document Quarterly Report DocumentQuarterlyReport	true
	dei	Document Period End Date DocumentPeriodEndDate	2021-09-30
	dei	Document Transition Report DocumentTransitionReport	false
	dei	Entity File Number EntityFileNumber	1-3548
	dei	Entity Registrant Name EntityRegistrantName	ALLETE, Inc.
	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MN
	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	41-0418150
	dei	Entity Address Address Line1 EntityAddressAddressLine1	30 West Superior Street
	dei	Entity Address City Or Town EntityAddressCityOrTown	Duluth
	dei	Entity Address State Or Province EntityAddressStateOrProvince	MN
	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	55802-2093
	dei	City Area Code CityAreaCode	218
	dei	Local Phone Number LocalPhoneNumber	279-5000
	dei	Security12b Title Security12bTitle	Common Stock, without par value
	dei	Trading Symbol TradingSymbol	ALE
	dei	Security Exchange Name SecurityExchangeName	NYSE
	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
	dei	Entity Small Business EntitySmallBusiness	false
	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
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CY2021Q3	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2021Q3	us-gaap	Minority Interest MinorityInterest	514500000	USD
CY2020Q4	us-gaap	Minority Interest MinorityInterest	505600000	USD
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CY2021Q3	ale	Transmission Services Utility TransmissionServicesUtility	19200000	USD
CY2020Q3	ale	Transmission Services Utility TransmissionServicesUtility	14900000	USD
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CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52400000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51900000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52300000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51800000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52500000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52000000.0	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52300000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51900000	shares
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.53
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.78
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.05
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.45
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.53
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.78
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.05
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.45
CY2021Q3	us-gaap	Profit Loss ProfitLoss	24100000	USD
CY2020Q3	us-gaap	Profit Loss ProfitLoss	38800000	USD
	us-gaap	Profit Loss ProfitLoss	89200000	USD
	us-gaap	Profit Loss ProfitLoss	120200000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-400000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-200000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1200000	USD
	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-500000	USD
CY2021Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	400000	USD
CY2020Q3	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	200000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	1200000	USD
	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	500000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	24500000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	39000000.0	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	90400000	USD
	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	120700000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-3500000	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-1900000	USD
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-18100000	USD
	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-6900000	USD
CY2021Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	28000000.0	USD
CY2020Q3	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	40900000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	108500000	USD
	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	127600000	USD
	us-gaap	Profit Loss ProfitLoss	89200000	USD
	us-gaap	Profit Loss ProfitLoss	120200000	USD
	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1700000	USD
	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1800000	USD
	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	-1800000	USD
	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	2300000	USD
	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	700000	USD
	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	0	USD
	us-gaap	Depreciation Depreciation	173400000	USD
	us-gaap	Depreciation Depreciation	161300000	USD
	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	8600000	USD
	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	8500000	USD
	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	7400000	USD
	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	7500000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-19400000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-27900000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	4600000	USD
	us-gaap	Share Based Compensation ShareBasedCompensation	4700000	USD
	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	3300000	USD
	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	100000	USD
	ale	Provision Payment For Interim Rate Refund ProvisionPaymentForInterimRateRefund	0	USD
	ale	Provision Payment For Interim Rate Refund ProvisionPaymentForInterimRateRefund	5200000	USD
	ale	Provisionfor Tax Reform Refund ProvisionforTaxReformRefund	0	USD
	ale	Provisionfor Tax Reform Refund ProvisionforTaxReformRefund	100000	USD
	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	900000	USD
	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1600000	USD
	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-800000	USD
	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-2800000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	15400000	USD
	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	2000000.0	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-7900000	USD
	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-8800000	USD
	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	4000000.0	USD
	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	2200000	USD
	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	20700000	USD
	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	12500000	USD
	us-gaap	Pension Contributions PensionContributions	10300000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-7400000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65200000	USD
	us-gaap	Pension Contributions PensionContributions	10700000	USD
	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	41300000	USD
	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	23500000	USD
	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-7400000	USD
	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-8200000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	209200000	USD
	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	241900000	USD
	ale	Cash Proceeds From Sale Of Available For Sale Securities CashProceedsFromSaleOfAvailableForSaleSecurities	3300000	USD
	ale	Cash Proceeds From Sale Of Available For Sale Securities CashProceedsFromSaleOfAvailableForSaleSecurities	6800000	USD
	ale	Payments For Purchase Of Available For Sale Securities PaymentsForPurchaseOfAvailableForSaleSecurities	3000000.0	USD
	ale	Payments For Purchase Of Available For Sale Securities PaymentsForPurchaseOfAvailableForSaleSecurities	7200000	USD
	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	17400000	USD
	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	91000000.0	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	384300000	USD
	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	540800000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-4300000	USD
	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-1000000.0	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-397100000	USD
	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-631200000	USD
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	31000000.0	USD
	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	12800000	USD
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	510600000	USD
	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	607400000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	280900000	USD
	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	207400000	USD
	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	28900000	USD
	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	67800000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	98700000	USD
	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	96000000.0	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2800000	USD
	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-2700000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	188100000	USD
	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	381900000	USD
	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	200000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	92500000	USD
CY2021Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65400000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	85100000	USD
CY2021Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2854500000	USD
CY2020Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2445600000	USD
CY2021Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2854500000	USD
CY2020Q3	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2445600000	USD
CY2021Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.63
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.6175
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.89
	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	1.8525
CY2021Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	59000000.0	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	44300000	USD
CY2020Q3	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	79000000.0	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	69300000	USD
CY2021Q3	us-gaap	Restricted Cash Current RestrictedCashCurrent	4100000	USD
CY2020Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	800000	USD
CY2020Q3	us-gaap	Restricted Cash Current RestrictedCashCurrent	3200000	USD
CY2019Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	2800000	USD
CY2021Q3	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	USD
CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	20100000	USD
CY2020Q3	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2900000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	20400000	USD
CY2021Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65400000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	65200000	USD
CY2020Q3	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	85100000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	92500000	USD
CY2021Q3	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	12400000	USD
CY2020Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	23100000	USD
CY2021Q3	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	55200000	USD
CY2020Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	51100000	USD
CY2021Q3	us-gaap	Other Inventory OtherInventory	22000000.0	USD
CY2020Q4	us-gaap	Other Inventory OtherInventory	0	USD
CY2021Q3	us-gaap	Inventory Net InventoryNet	89600000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	74200000	USD
CY2021Q3	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	23400000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	25500000	USD
CY2021Q3	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	17700000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	22400000	USD
CY2021Q3	us-gaap	Real Estate Investments RealEstateInvestments	17600000	USD
CY2020Q4	us-gaap	Real Estate Investments RealEstateInvestments	18200000	USD
CY2021Q3	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	2300000	USD
CY2020Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	20100000	USD
CY2021Q3	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	35800000	USD
CY2020Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	34200000	USD
CY2021Q3	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	82900000	USD
CY2020Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	86400000	USD
CY2021Q3	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	179700000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	206800000	USD
CY2021Q3	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	27500000	USD
CY2020Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	7400000	USD
CY2021Q3	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	12600000	USD
CY2020Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	12500000	USD
CY2021Q3	ale	Public Utilities Fuel Adjustment Clause PublicUtilitiesFuelAdjustmentClause	2600000	USD
CY2020Q4	ale	Public Utilities Fuel Adjustment Clause PublicUtilitiesFuelAdjustmentClause	3700000	USD
CY2021Q3	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	5000000.0	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	5900000	USD
CY2021Q3	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	36300000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	37200000	USD
CY2021Q3	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	84000000.0	USD
CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	66700000	USD
CY2021Q3	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	170900000	USD
CY2020Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	166600000	USD
CY2021Q3	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	42600000	USD
CY2020Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	52100000	USD
CY2021Q3	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	12700000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	16500000	USD
CY2021Q3	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	51900000	USD
CY2020Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	50100000	USD
CY2021Q3	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	278100000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	285300000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	6100000	USD
	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	9100000	USD
	us-gaap	Interest Paid Net InterestPaidNet	54900000	USD
	us-gaap	Interest Paid Net InterestPaidNet	48800000	USD
	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	12100000	USD
	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	88400000	USD
	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	3500000	USD
	us-gaap	Increase Decrease In Asset Retirement Obligations IncreaseDecreaseInAssetRetirementObligations	2100000	USD
	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1700000	USD
	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1800000	USD
	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.
CY2021Q3	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	502900000	USD
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	480900000	USD
CY2021Q3	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	9000000.0	USD
CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	7600000	USD
CY2021Q3	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	509500000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	524800000	USD
CY2021Q3	us-gaap	Regulatory Liabilities RegulatoryLiabilities	518500000	USD
CY2020Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	532400000	USD
CY2021Q3	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	1500000	USD
CY2021Q3	ale	Availableforsale Securities Debt Maturities After One Year Through Three Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterOneYearThroughThreeYearsFairValue	3400000	USD
CY2021Q3	ale	Availableforsale Securities Debt Maturities After Three Years Through Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterThreeYearsThroughFiveYearsFairValue	3000000	USD
CY2021Q3	ale	Availableforsale Securities Debt Maturities After Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterFiveYearsFairValue	500000	USD
CY2021Q3	us-gaap	Long Term Debt LongTermDebt	2036100000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	1806400000	USD
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1602400000	USD
CY2021Q3	ale	Debt Current Gross DebtCurrentGross	377600000	USD
CY2021Q3	ale	Unamortized Debt Issuance Expense Debt Current UnamortizedDebtIssuanceExpenseDebtCurrent	200000	USD
CY2021Q3	us-gaap	Debt Current DebtCurrent	377400000	USD
CY2021Q3	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1658500000	USD
CY2021Q3	ale	Unamortized Debt Issuance Expense Long Term Debt Excluding Current Maturities UnamortizedDebtIssuanceExpenseLongTermDebtExcludingCurrentMaturities	9100000	USD
CY2021Q3	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1649400000	USD
CY2021Q3	ale	Debt Long Termand Short Term Combined Amount Gross DebtLongTermandShortTermCombinedAmountGross	2036100000	USD
CY2021Q3	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	9300000	USD
CY2021Q3	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	2026800000	USD
CY2020Q4	ale	Debt Current Gross DebtCurrentGross	204000000.0	USD
CY2020Q4	ale	Unamortized Debt Issuance Expense Debt Current UnamortizedDebtIssuanceExpenseDebtCurrent	300000	USD
CY2020Q4	us-gaap	Debt Current DebtCurrent	203700000	USD
CY2020Q4	ale	Unamortized Debt Issuance Expense Long Term Debt Excluding Current Maturities UnamortizedDebtIssuanceExpenseLongTermDebtExcludingCurrentMaturities	9200000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1593200000	USD
CY2020Q4	ale	Debt Long Termand Short Term Combined Amount Gross DebtLongTermandShortTermCombinedAmountGross	1806400000	USD
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	9500000	USD
CY2020Q4	us-gaap	Debt Longterm And Shortterm Combined Amount DebtLongtermAndShorttermCombinedAmount	1796900000	USD
CY2021Q3	ale	Debt Instrument Actual Indebtedness To Total Capital Ratio DebtInstrumentActualIndebtednessToTotalCapitalRatio	0.43
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	27600000	USD
CY2021Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	27600000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	40700000	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	40700000	USD
CY2021Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52400000	shares
CY2021Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2021Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52500000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51900000	shares
CY2020Q3	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2020Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52000000.0	shares
CY2021Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.53
CY2021Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.53
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.78
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.78
	us-gaap	Net Income Loss NetIncomeLoss	107300000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	107300000	USD
	us-gaap	Net Income Loss NetIncomeLoss	127100000	USD
	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	127100000	USD
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	52300000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	0	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	52300000	shares
	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51800000	shares
	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51900000	shares
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.05
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.05
	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.45
	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.45
CY2021Q3	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2020Q3	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2021Q3	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	100000	USD
CY2020Q3	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	100000	USD
	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	100000	USD
	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	100000	USD
CY2021Q3	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	100000	USD
CY2020Q3	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	100000	USD
	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	100000	USD
	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	100000	USD
CY2021Q3	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-5800000	USD
CY2020Q3	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-8300000	USD
	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-26300000	USD
	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-34500000	USD
CY2021Q3	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	900000	USD
CY2020Q3	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	2900000	USD
	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	7300000	USD
	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	7100000	USD
CY2021Q3	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-100000	USD
CY2020Q3	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-200000	USD
	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-400000	USD
	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-500000	USD
CY2021Q3	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5000000.0	USD
CY2020Q3	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-5600000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-19400000	USD
	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-27900000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-4900000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5500000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-27800000	USD
CY2021Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	19200000	USD
CY2020Q3	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	33300000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	69900000	USD
	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	92400000	USD
CY2021Q3	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2020Q3	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2021Q3	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	4000000.0	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	7000000.0	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	14700000	USD
	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	19400000	USD
CY2021Q3	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	700000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	2400000	USD
	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5800000	USD
	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	5700000	USD
CY2021Q3	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	9500000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	12500000	USD
	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	36600000	USD
	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	45900000	USD
CY2021Q3	ale	Effective Income Tax Rate Reconciliation Regulatory Differences EffectiveIncomeTaxRateReconciliationRegulatoryDifferences	-2100000	USD
CY2020Q3	ale	Effective Income Tax Rate Reconciliation Regulatory Differences EffectiveIncomeTaxRateReconciliationRegulatoryDifferences	-3200000	USD
	ale	Effective Income Tax Rate Reconciliation Regulatory Differences EffectiveIncomeTaxRateReconciliationRegulatoryDifferences	-6700000	USD
	ale	Effective Income Tax Rate Reconciliation Regulatory Differences EffectiveIncomeTaxRateReconciliationRegulatoryDifferences	-8500000	USD
CY2021Q3	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	-800000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	-400000	USD
	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	-3900000	USD
	us-gaap	Income Tax Reconciliation Minority Interest Income Expense IncomeTaxReconciliationMinorityInterestIncomeExpense	-1500000	USD
CY2021Q3	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	0	USD
CY2020Q3	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	0	USD
	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	500000	USD
	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-100000	USD
CY2021Q3	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	1200000	USD
CY2020Q3	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	400000	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	-900000	USD
	us-gaap	Income Tax Reconciliation Other Reconciling Items IncomeTaxReconciliationOtherReconcilingItems	100000	USD
CY2021Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-4900000	USD
CY2020Q3	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-5500000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-19300000	USD
	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-27800000	USD
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.276
	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-0.301
CY2021Q3	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1500000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	1400000	USD
CY2021Q3	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	600000	USD
CY2021Q3	us-gaap	Revenues Revenues	345400000	USD
CY2020Q3	us-gaap	Revenues Revenues	293900000	USD
	us-gaap	Revenues Revenues	1020200000	USD
	us-gaap	Revenues Revenues	848700000	USD
CY2021Q3	us-gaap	Net Income Loss NetIncomeLoss	27600000	USD
CY2020Q3	us-gaap	Net Income Loss NetIncomeLoss	40700000	USD
	us-gaap	Net Income Loss NetIncomeLoss	107300000	USD
	us-gaap	Net Income Loss NetIncomeLoss	127100000	USD
CY2021Q3	us-gaap	Assets Assets	6332200000	USD
CY2020Q4	us-gaap	Assets Assets	6084600000	USD

Files In Submission

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report.css	Edgar Link	pending
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$ALE
ALLETE INC Stock $ale

2021 Q3 Form 10-Q Financial Statement

#000006675621000081 Filed on November 04, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE ALLETE INC Stock $ale

2021 Q3 Form 10-Q Financial Statement

#000006675621000081 Filed on November 04, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE
ALLETE INC Stock $ale