$ALE
ALLETE INC Stock $ale

$ale Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000006675620000016 Filed on February 13, 2020

Income Statement

Concept	2019 Q4	2019	2018 Q4
Revenue	$304.6M	$1.241B	$448.3M
YoY Change	-32.05%	-17.22%	32.67%
Cost Of Revenue	$18.80M	$80.60M	$109.4M
YoY Change	-82.82%	-63.03%	162.35%
Gross Profit	$285.8M	$1.160B	$338.9M
YoY Change	-15.67%	-9.43%	13.65%
Gross Profit Margin	93.83%	93.5%	75.6%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$53.40M	$202.0M	$53.40M
YoY Change	0.0%	-1.75%	97.05%
% of Gross Profit	18.68%	17.42%	15.76%
Operating Expenses	$236.0M	$264.3M	$274.9M
YoY Change	-14.15%	-22.38%	3.74%
Operating Profit	$49.80M	$179.8M	$64.00M
YoY Change	-22.19%	-10.64%	98.14%
Interest Expense	-$9.600M	$64.90M	-$11.80M
YoY Change	-18.64%	-4.42%	-2.48%
% of Operating Profit	-19.28%	36.1%	-18.44%
Other Income/Expense, Net	$4.100M	-$900.0K	$2.100M
YoY Change	95.24%	-97.89%	425.0%
Pretax Income	$47.30M	$178.9M	$54.30M
YoY Change	-12.89%	12.8%	152.56%
Income Tax	-$2.300M	-$6.600M	-$23.20M
% Of Pretax Income	-4.86%	-3.69%	-42.73%
Net Earnings	$49.70M	$185.6M	$61.10M
YoY Change	-18.66%	6.61%	47.58%
Net Earnings / Revenue	16.32%	14.96%	13.63%
Basic Earnings Per Share	$0.96	$3.59	$1.19
Diluted Earnings Per Share	$0.96	$3.59	$1.18
COMMON SHARES
Basic Shares Outstanding		51.60M shares
Diluted Shares Outstanding		51.70M shares

Balance Sheet

Concept	2019 Q4	2019	2018 Q4
SHORT-TERM ASSETS
Cash & Short-Term Investments	$69.30M	$69.30M	$69.10M
YoY Change	0.29%	0.29%	-30.13%
Cash & Equivalents	$69.30M	$69.30M	$69.10M
Short-Term Investments
Other Short-Term Assets	$31.00M	$31.00M	$34.10M
YoY Change	-9.09%	-9.09%	-9.31%
Inventory	$72.80M	$72.80M	$86.70M
Prepaid Expenses
Receivables	$96.40M	$96.40M	$144.4M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$269.5M	$269.5M	$334.3M
YoY Change	-19.38%	-19.38%	-9.03%
LONG-TERM ASSETS
Property, Plant & Equipment	$4.377B	$4.377B	$3.904B
YoY Change	12.1%	11.41%	2.15%
Goodwill	$0.00		$148.5M
YoY Change	-100.0%		0.13%
Intangibles	$1.000M		$74.80M
YoY Change	-98.66%		-3.61%
Long-Term Investments	$197.6M	$197.6M	$161.1M
YoY Change	22.66%	6.35%	35.72%
Other Assets	$218.2M	$637.7M	$152.4M
YoY Change	43.18%	29.4%	41.5%
Total Long-Term Assets	$5.213B	$5.213B	$4.831B
YoY Change	7.92%	7.92%	2.51%
TOTAL ASSETS
Total Short-Term Assets	$269.5M	$269.5M	$334.3M
Total Long-Term Assets	$5.213B	$5.213B	$4.831B
Total Assets	$5.483B	$5.483B	$5.165B
YoY Change	6.15%	6.15%	1.67%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$165.2M	$165.2M	$149.8M
YoY Change	10.28%	10.28%	9.9%
Accrued Expenses	$25.00M	$25.00M	$17.90M
YoY Change	39.66%	39.66%	1.7%
Deferred Revenue	$0.00		$7.600M
YoY Change	-100.0%		-12.64%
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$212.9M	$212.9M	$57.50M
YoY Change	270.26%	270.26%	-10.3%
Total Short-Term Liabilities	$507.4M	$507.4M	$405.1M
YoY Change	25.25%	25.25%	15.35%
LONG-TERM LIABILITIES
Long-Term Debt	$1.401B	$1.401B	$1.429B
YoY Change	-1.93%	-1.93%	-0.74%
Other Long-Term Liabilities	$293.0M	$1.026B	$262.6M
YoY Change	11.58%	7.78%	-1.68%
Total Long-Term Liabilities	$1.694B	$2.427B	$1.691B
YoY Change	0.17%	1.95%	-0.89%
TOTAL LIABILITIES
Total Short-Term Liabilities	$507.4M	$507.4M	$405.1M
Total Long-Term Liabilities	$1.694B	$2.427B	$1.691B
Total Liabilities	$3.147B	$3.251B	$3.009B
YoY Change	4.59%	8.03%	-0.09%
SHAREHOLDERS EQUITY
Retained Earnings	$818.8M		$754.6M
YoY Change	8.51%		9.46%
Common Stock	$1.437B		$1.429B
YoY Change	0.57%		1.93%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$2.232B	$2.232B	$2.156B
YoY Change
Total Liabilities & Shareholders Equity	$5.483B	$5.483B	$5.165B
YoY Change	6.15%	6.15%	1.67%

Cashflow Statement

Concept	2019 Q4	2019	2018 Q4
OPERATING ACTIVITIES
Net Income	$49.70M	$185.6M	$61.10M
YoY Change	-18.66%	6.61%	47.58%
Depreciation, Depletion And Amortization	$53.40M	$202.0M	$53.40M
YoY Change	0.0%	-1.75%	97.05%
Cash From Operating Activities	$73.10M	$246.9M	$135.0M
YoY Change	-45.85%	-42.75%	41.07%
INVESTING ACTIVITIES
Capital Expenditures	-$175.8M	$597.1M	-$111.4M
YoY Change	57.81%	91.13%	42.46%
Acquisitions		$0.00
YoY Change
Other Investing Activities	-$9.500M	-$15.50M	-$29.80M
YoY Change	-68.12%	106.67%	-3411.11%
Cash From Investing Activities	-$185.3M	-$342.7M	-$141.2M
YoY Change	31.23%	-1.3%	82.66%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$1.900M
YoY Change		-90.64%
Debt Paid & Issued, Net		$72.20M
YoY Change		-24.4%
Cash From Financing Activities	69.50M	$109.3M	-56.30M
YoY Change	-223.45%	-194.88%	135.56%
NET CHANGE
Cash From Operating Activities	73.10M	$246.9M	135.0M
Cash From Investing Activities	-185.3M	-$342.7M	-141.2M
Cash From Financing Activities	69.50M	$109.3M	-56.30M
Net Change In Cash	-42.70M	$13.50M	-62.50M
YoY Change	-31.68%	-143.41%	1036.36%
FREE CASH FLOW
Cash From Operating Activities	$73.10M	$246.9M	$135.0M
Capital Expenditures	-$175.8M	$597.1M	-$111.4M
Free Cash Flow	$248.9M	-$350.2M	$246.4M
YoY Change	1.01%	-394.53%	41.69%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
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CY2019	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	MN
CY2019	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	41-0418150
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CY2017	us-gaap	Profit Loss ProfitLoss	172200000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-100000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	185600000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	174100000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	172200000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51600000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51300000	shares
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50800000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51700000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51500000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51000000.0	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.59
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.39
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.39
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.59
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2019	us-gaap	Profit Loss ProfitLoss	185500000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	174100000	USD
CY2018	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	-100000	USD
CY2018	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	23600000	USD
CY2017	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	23600000	USD
CY2019	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	13000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	900000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-3500000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-1000000.0	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-4700000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	3700000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	900000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	172200000	USD
CY2019	us-gaap	Other Comprehensive Income Unrealized Holding Gain Loss On Securities Arising During Period Net Of Tax OtherComprehensiveIncomeUnrealizedHoldingGainLossOnSecuritiesArisingDuringPeriodNetOfTax	200000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	189200000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	175000000.0	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	177800000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-100000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	0	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	0	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	189300000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	175000000.0	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	177800000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	185500000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	174100000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	172200000	USD
CY2019	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2300000	USD
CY2018	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1200000	USD
CY2017	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1200000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	5600000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	2300000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	3200000	USD
CY2019	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	0	USD
CY2018	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-2000000.0	USD
CY2017	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-700000	USD
CY2019	us-gaap	Increase Decrease In Deferred Fuel Costs IncreaseDecreaseInDeferredFuelCosts	0	USD
CY2018	us-gaap	Increase Decrease In Deferred Fuel Costs IncreaseDecreaseInDeferredFuelCosts	0	USD
CY2017	us-gaap	Increase Decrease In Deferred Fuel Costs IncreaseDecreaseInDeferredFuelCosts	-19500000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	1700000	USD
CY2018	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-1000000.0	USD
CY2017	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	-400000	USD
CY2019	us-gaap	Depreciation Depreciation	200600000	USD
CY2018	us-gaap	Depreciation Depreciation	200100000	USD
CY2017	us-gaap	Depreciation Depreciation	171900000	USD
CY2019	ale	Amortizationof Power Purchase Agreements AmortizationofPowerPurchaseAgreements	11600000	USD
CY2018	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	10400000	USD
CY2017	us-gaap	Other Depreciation And Amortization OtherDepreciationAndAmortization	10200000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-6700000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-15800000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	14400000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	6300000	USD
CY2018	us-gaap	Share Based Compensation ShareBasedCompensation	6800000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	6600000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	1200000	USD
CY2018	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	8600000	USD
CY2017	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	10100000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	-100000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	1100000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	800000	USD
CY2019	ale	Provisionfor Interim Rate Refund ProvisionforInterimRateRefund	-40000000.0	USD
CY2018	ale	Provisionfor Interim Rate Refund ProvisionforInterimRateRefund	16300000	USD
CY2017	ale	Provisionfor Interim Rate Refund ProvisionforInterimRateRefund	32300000	USD
CY2019	ale	Provisionfor Tax Reform Refund ProvisionforTaxReformRefund	10400000	USD
CY2018	ale	Provisionfor Tax Reform Refund ProvisionforTaxReformRefund	-10700000	USD
CY2017	ale	Provisionfor Tax Reform Refund ProvisionforTaxReformRefund	0	USD
	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	23600000	USD
CY2018	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2017	us-gaap	Gain Loss On Sale Of Business GainLossOnSaleOfBusiness	0	USD
CY2019	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-22600000	USD
CY2018	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	10700000	USD
CY2017	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	8000000.0	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	4100000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-55500000	USD
CY2017	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-11900000	USD
CY2019	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	-300000	USD
CY2018	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	4000000.0	USD
CY2017	us-gaap	Increase Decrease In Prepaid Deferred Expense And Other Assets IncreaseDecreaseInPrepaidDeferredExpenseAndOtherAssets	5300000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-8800000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	13600000	USD
CY2017	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-7500000	USD
CY2019	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-13700000	USD
CY2018	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	6700000	USD
CY2017	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	1800000	USD
CY2019	us-gaap	Pension Contributions PensionContributions	10400000	USD
CY2018	us-gaap	Pension Contributions PensionContributions	15000000.0	USD
CY2017	us-gaap	Pension Contributions PensionContributions	1700000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	25100000	USD
CY2018	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-6700000	USD
CY2017	us-gaap	Increase Decrease In Other Noncurrent Assets IncreaseDecreaseInOtherNoncurrentAssets	-33700000	USD
CY2019	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-15900000	USD
CY2018	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-3900000	USD
CY2017	us-gaap	Increase Decrease In Other Noncurrent Liabilities IncreaseDecreaseInOtherNoncurrentLiabilities	-31700000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	249500000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	433100000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	402900000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	12100000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	10200000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities ProceedsFromSaleOfAvailableForSaleSecurities	10100000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	12200000	USD
CY2018	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	13300000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities PaymentsToAcquireAvailableForSaleSecurities	8600000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	0	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	18500000	USD
CY2019	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	37900000	USD
CY2018	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	39200000	USD
CY2017	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	7800000	USD
CY2019	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	8300000	USD
CY2018	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	0	USD
CY2017	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	0	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	597100000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	312400000	USD
CY2017	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	208500000	USD
CY2019	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	268600000	USD
CY2018	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2017	us-gaap	Proceeds From Sale Of Productive Assets ProceedsFromSaleOfProductiveAssets	0	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-12900000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-5700000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-4300000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-345300000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-349000000.0	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-229000000.0	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1900000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	20300000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	86000000.0	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	201900000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	75600000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	131500000	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	72200000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	95500000	USD
CY2017	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	189600000	USD
CY2019	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	103800000	USD
CY2018	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2017	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2019	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	3800000	USD
CY2018	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	0	USD
CY2017	us-gaap	Payment For Contingent Consideration Liability Financing Activities PaymentForContingentConsiderationLiabilityFinancingActivities	19700000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	121400000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	115000000.0	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	108700000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-900000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-600000	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-1600000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	109300000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-115200000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-102100000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	13500000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-31100000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	71800000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	79000000.0	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	110100000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	38300000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	92500000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	79000000.0	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	110100000	USD
CY2019	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	103800000	USD
CY2018	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2017	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	0	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2335600000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2155800000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	2068200000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.35
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.24
CY2017	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.14
CY2019	us-gaap	Number Of Reportable Segments NumberOfReportableSegments	3
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	69300000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	69100000	USD
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	98900000	USD
CY2019Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	2800000	USD
CY2018Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	1300000	USD
CY2017Q4	us-gaap	Restricted Cash Current RestrictedCashCurrent	2600000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	20400000	USD
CY2018Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	8600000	USD
CY2017Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	8600000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	92500000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	79000000.0	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	110100000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	63500000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	66000000.0	USD
CY2017	us-gaap	Interest Paid Net InterestPaidNet	64500000	USD
CY2019	ale	Recognitionof Rightofuse Assetsand Lease Liabilities RecognitionofRightofuseAssetsandLeaseLiabilities	28700000	USD
CY2018	ale	Recognitionof Rightofuse Assetsand Lease Liabilities RecognitionofRightofuseAssetsandLeaseLiabilities	0	USD
CY2017	ale	Recognitionof Rightofuse Assetsand Lease Liabilities RecognitionofRightofuseAssetsandLeaseLiabilities	0	USD
CY2019	ale	Increaseto Regulatory Assets IncreasetoRegulatoryAssets	0	USD
CY2018	ale	Increaseto Regulatory Assets IncreasetoRegulatoryAssets	0	USD
CY2017	ale	Increaseto Regulatory Assets IncreasetoRegulatoryAssets	80900000	USD
CY2019Q4	ale	Decreasein Investmentof Equity Method Investee DecreaseinInvestmentofEquityMethodInvestee	0	USD
CY2018Q4	ale	Decreasein Investmentof Equity Method Investee DecreaseinInvestmentofEquityMethodInvestee	0	USD
CY2017Q4	ale	Decreasein Investmentof Equity Method Investee DecreaseinInvestmentofEquityMethodInvestee	-27900000	USD
CY2019	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	0	USD
CY2018	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	0	USD
CY2017	us-gaap	Increase Decrease In Deferred Income Taxes IncreaseDecreaseInDeferredIncomeTaxes	-353600000	USD
CY2019	ale	Increaseto Regulatory Liabilities IncreasetoRegulatoryLiabilities	0	USD
CY2018	ale	Increaseto Regulatory Liabilities IncreasetoRegulatoryLiabilities	0	USD
CY2017	ale	Increaseto Regulatory Liabilities IncreasetoRegulatoryLiabilities	393600000	USD
CY2019	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	33900000	USD
CY2018	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	-100000	USD
CY2017	ale	Increase Decreasein Accounts Payablefor Capital Additionsto Property Plantand Equipment IncreaseDecreaseinAccountsPayableforCapitalAdditionstoPropertyPlantandEquipment	67200000	USD
CY2019	ale	Reclassificationof Property Plantand Equipmentto Inventory ReclassificationofPropertyPlantandEquipmenttoInventory	0	USD
CY2018	ale	Reclassificationof Property Plantand Equipmentto Inventory ReclassificationofPropertyPlantandEquipmenttoInventory	46300000	USD
CY2017	ale	Reclassificationof Property Plantand Equipmentto Inventory ReclassificationofPropertyPlantandEquipmenttoInventory	0	USD
CY2019	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	20700000	USD
CY2018	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	14200000	USD
CY2017	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	-15600000	USD
CY2019	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	2300000	USD
CY2018	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1200000	USD
CY2017	us-gaap	Increase Decrease In Allowance For Equity Funds Used During Construction IncreaseDecreaseInAllowanceForEquityFundsUsedDuringConstruction	1200000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	0	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	0	USD
CY2017	us-gaap	Stock Issued During Period Value Employee Benefit Plan StockIssuedDuringPeriodValueEmployeeBenefitPlan	13500000	USD
CY2018	ale	Reclassificationof Property Plantand Equipmentto Inventory ReclassificationofPropertyPlantandEquipmenttoInventory	46300000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	77200000	USD
CY2018Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	121700000	USD
CY2019Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	20100000	USD
CY2018Q4	us-gaap	Unbilled Receivables Current UnbilledReceivablesCurrent	24400000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	900000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	1700000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	96400000	USD
CY2018Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	144400000	USD
CY2019Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	25900000	USD
CY2018Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	26000000.0	USD
CY2019Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	46900000	USD
CY2018Q4	us-gaap	Inventory Supplies Net Of Reserves InventorySuppliesNetOfReserves	44200000	USD
CY2019Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	0	USD
CY2018Q4	us-gaap	Inventory Raw Materials InventoryRawMaterials	2800000	USD
CY2019Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	0	USD
CY2018Q4	us-gaap	Inventory Work In Process InventoryWorkInProcess	6100000	USD
CY2019Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	0	USD
CY2018Q4	us-gaap	Inventory Finished Goods InventoryFinishedGoods	8400000	USD
CY2019Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	0	USD
CY2018Q4	us-gaap	Inventory Valuation Reserves InventoryValuationReserves	800000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	72800000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	86700000	USD
CY2019	us-gaap	Impairment Of Real Estate ImpairmentOfRealEstate	0	USD
CY2019Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	28000000.0	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	30700000	USD
CY2019Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	0	USD
CY2018Q4	us-gaap	Notes Receivable Gross NotesReceivableGross	10400000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	28600000	USD
CY2018Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	0	USD
CY2019Q4	us-gaap	Real Estate Investments RealEstateInvestments	21900000	USD
CY2018Q4	us-gaap	Real Estate Investments RealEstateInvestments	24400000	USD
CY2019Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	20400000	USD
CY2018Q4	us-gaap	Restricted Cash Noncurrent RestrictedCashNoncurrent	8600000	USD
CY2019Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	37500000	USD
CY2018Q4	ale	Other Postretirement Benefit Plans OtherPostretirementBenefitPlans	400000	USD
CY2019Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	80800000	USD
CY2018Q4	us-gaap	Other Assets Miscellaneous Noncurrent OtherAssetsMiscellaneousNoncurrent	77900000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	217200000	USD
CY2018Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	152400000	USD
CY2019Q4	ale	Provisionfor Interim Rate Refunds ProvisionforInterimRateRefunds	0	USD
CY2018Q4	ale	Provisionfor Interim Rate Refunds ProvisionforInterimRateRefunds	40000000.0	USD
CY2019Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	12300000	USD
CY2018Q4	ale	Power Purchase Agreement Current Liability PowerPurchaseAgreementCurrentLiability	12600000	USD
CY2019Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	0	USD
CY2018Q4	us-gaap	Contract With Customer Liability Current ContractWithCustomerLiabilityCurrent	7600000	USD
CY2019Q4	ale	Provisionfor Tax Reform Refunds ProvisionforTaxReformRefunds	200000	USD
CY2018Q4	ale	Provisionfor Tax Reform Refunds ProvisionforTaxReformRefunds	10700000	USD
CY2019Q4	us-gaap	Business Combination Contingent Consideration Liability Current BusinessCombinationContingentConsiderationLiabilityCurrent	0	USD
CY2018Q4	us-gaap	Business Combination Contingent Consideration Liability Current BusinessCombinationContingentConsiderationLiabilityCurrent	3800000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	6900000	USD
CY2018Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	0	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	41000000.0	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	53800000	USD
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	60400000	USD
CY2018Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	128500000	USD
CY2019Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	160300000	USD
CY2018Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	138600000	USD
CY2019Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	64600000	USD
CY2018Q4	ale	Power Purchase Agreement Noncurrent Liability PowerPurchaseAgreementNoncurrentLiability	76900000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	21800000	USD
CY2018Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	0	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	46300000	USD
CY2018Q4	us-gaap	Other Accrued Liabilities Noncurrent OtherAccruedLiabilitiesNoncurrent	47100000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	293000000.0	USD
CY2018Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	262600000	USD
CY2019	us-gaap	Lessee Operating Lease Residual Value Guarantee Description LesseeOperatingLeaseResidualValueGuaranteeDescription	Our largest operating lease is for the dragline at BNI Energy which includes a termination payment at the end of the lease term if we do not exercise our purchase option.
CY2019Q4	us-gaap	Residual Value Of Leased Asset ResidualValueOfLeasedAsset	3000000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	9400000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	9400000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	28600000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	28600000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	6900000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	21800000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	28700000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	6600000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	6000000.0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	5000000.0	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	3200000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	2900000	USD
CY2019Q4	us-gaap	Operating Leases Future Minimum Payments Due Thereafter OperatingLeasesFutureMinimumPaymentsDueThereafter	11500000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	35200000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	6500000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	28700000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	6900000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	21800000	USD
CY2019Q4	ale	Large Power Customer Contracts LargePowerCustomerContracts	8
CY2019	us-gaap	Revenue Performance Obligation Description Of Payment Terms RevenuePerformanceObligationDescriptionOfPaymentTerms	Payment terms and conditions vary across our businesses. Aside from taconite-producing Large Power Customers, payment terms generally require payment to be made within 15 to 30 days from the end of the period that the service has been rendered or goods provided. In the case of its taconite-producing Large Power Customers, as permitted by the MPUC, Minnesota Power requires weekly payments for electric usage based on monthly energy usage estimates.
CY2019Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	28000000.0	USD
CY2018Q4	us-gaap	Contract With Customer Asset Net Noncurrent ContractWithCustomerAssetNetNoncurrent	30700000	USD
CY2019	us-gaap	Capitalized Contract Cost Amortization CapitalizedContractCostAmortization	2600000	USD
CY2019	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	0	USD
CY2018	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-2000000.0	USD
CY2017	us-gaap	Business Combination Contingent Consideration Arrangements Change In Amount Of Contingent Consideration Liability1 BusinessCombinationContingentConsiderationArrangementsChangeInAmountOfContingentConsiderationLiability1	-700000	USD
CY2019	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	0	USD
CY2018	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	2000000.0	USD
CY2017	us-gaap	Other Operating Income Expense Net OtherOperatingIncomeExpenseNet	700000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	4377000000.0	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	18700000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	7800000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	6300000	USD
CY2019	ale	Morelikelythannotdefined Morelikelythannotdefined	0.50
CY2018Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	3904400000	USD
CY2017Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	122700000	USD
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	7000000.0	USD
CY2018	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	5300000	USD
CY2018	ale	Costs Incurred Capitalized Asset Retirement Obligation Costs CostsIncurredCapitalizedAssetRetirementObligationCosts	14200000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	138600000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	7200000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	1400000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	4600000	USD
CY2019	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	17700000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	160300000	USD
CY2019Q4	us-gaap	Jointly Owned Utility Plant Gross Ownership Amount Of Plant In Service JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService	763700000	USD
CY2019Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Plant Accumulated Depreciation JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation	272400000	USD
CY2019Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Construction Work In Progress JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress	5700000	USD
CY2018Q4	us-gaap	Jointly Owned Utility Plant Gross Ownership Amount Of Plant In Service JointlyOwnedUtilityPlantGrossOwnershipAmountOfPlantInService	751100000	USD
CY2018Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Plant Accumulated Depreciation JointlyOwnedUtilityPlantOwnershipAmountOfPlantAccumulatedDepreciation	240900000	USD
CY2018Q4	us-gaap	Jointly Owned Utility Plant Ownership Amount Of Construction Work In Progress JointlyOwnedUtilityPlantOwnershipAmountOfConstructionWorkInProgress	6400000	USD
CY2019	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.
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	420500000	USD
CY2018Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	389500000	USD
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	1900000	USD
CY2018Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	55100000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	560300000	USD
CY2018Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	512100000	USD
CY2019Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	562200000	USD
CY2018Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	567200000	USD
CY2019	us-gaap	Proceeds From Equity Method Investment Dividends Or Distributions Return Of Capital ProceedsFromEquityMethodInvestmentDividendsOrDistributionsReturnOfCapital	8300000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	0	USD
CY2018Q4	us-gaap	Goodwill Goodwill	148500000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	58200000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1500000	USD
CY2019	ale	Finite Lived Intangible Assets Other Changes FiniteLivedIntangibleAssetsOtherChanges	55700000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	1000000.0	USD
CY2018Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	74800000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1500000	USD
CY2019	ale	Intangible Assets Other Changes IntangibleAssetsOtherChanges	72300000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	1000000.0	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	1500000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	5600000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Maturities Within One Year Fair Value AvailableForSaleSecuritiesDebtMaturitiesWithinOneYearFairValue	2100000	USD
CY2019Q4	ale	Availableforsale Securities Debt Maturities After One Year Through Three Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterOneYearThroughThreeYearsFairValue	7200000	USD
CY2019Q4	ale	Availableforsale Securities Debt Maturities After Three Years Through Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterThreeYearsThroughFiveYearsFairValue	0	USD
CY2019Q4	ale	Availableforsale Securities Debt Maturities After Five Years Fair Value AvailableforsaleSecuritiesDebtMaturitiesAfterFiveYearsFairValue	400000	USD
CY2019	us-gaap	Fair Value Measurement With Unobservable Inputs Reconciliation Recurring Basis Liability Period Increase Decrease FairValueMeasurementWithUnobservableInputsReconciliationRecurringBasisLiabilityPeriodIncreaseDecrease	3800000	USD
CY2019Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1622600000	USD
CY2018Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	1495200000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	197600000	USD
CY2018Q4	us-gaap	Equity Method Investments EquityMethodInvestments	161100000	USD
CY2019	us-gaap	Property Plant And Equipment Impairment PropertyPlantAndEquipmentImpairment	The Company assesses the impairment of property, plant, and equipment whenever events or changes in circumstances indicate that the carrying amount of property, plant, and equipment assets may not be recoverable.
CY2019Q4	us-gaap	Debt Current DebtCurrent	212900000	USD
CY2018Q4	us-gaap	Debt Current DebtCurrent	57500000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Current Net DeferredFinanceCostsCurrentNet	400000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1400900000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1428500000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Noncurrent Net DeferredFinanceCostsNoncurrentNet	8400000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	213300000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	98600000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	88800000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	88800000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	73500000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	1059600000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	8800000	USD
CY2018Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	9200000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	1613800000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	1486000000.0	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	212900000	USD
CY2018Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	57500000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1400900000	USD
CY2018Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	1428500000	USD
CY2019Q4	ale	Debt Instrument Required Indebtedness To Total Capital Ratio DebtInstrumentRequiredIndebtednessToTotalCapitalRatio	0.65
CY2019Q4	ale	Debt Instrument Actual Indebtedness To Total Capital Ratio DebtInstrumentActualIndebtednessToTotalCapitalRatio	0.42
CY2019	us-gaap	Net Income Loss NetIncomeLoss	185600000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	185600000	USD
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51600000	shares
CY2019	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	100000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51700000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.59
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.59
CY2018	us-gaap	Net Income Loss NetIncomeLoss	174100000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	174100000	USD
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	51300000	shares
CY2018	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	200000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51500000	shares
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.39
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2017	us-gaap	Net Income Loss NetIncomeLoss	172200000	USD
CY2017	us-gaap	Weighted Average Number Diluted Shares Outstanding Adjustment WeightedAverageNumberDilutedSharesOutstandingAdjustment	200000	shares
CY2017	us-gaap	Net Income Loss Available To Common Stockholders Diluted NetIncomeLossAvailableToCommonStockholdersDiluted	172200000	USD
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	50800000	shares
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	51000000.0	shares
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.39
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.38
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2017	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	100000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	300000	USD
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	300000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	100000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	300000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	300000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-27800000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-26200000	USD
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	12100000	USD
CY2019	ale	Deferred Federal Income Tax Expense Benefit Remeasurementof Deferred Income Taxes DeferredFederalIncomeTaxExpenseBenefitRemeasurementofDeferredIncomeTaxes	0	USD
CY2018	ale	Deferred Federal Income Tax Expense Benefit Remeasurementof Deferred Income Taxes DeferredFederalIncomeTaxExpenseBenefitRemeasurementofDeferredIncomeTaxes	0	USD
CY2017	ale	Deferred Federal Income Tax Expense Benefit Remeasurementof Deferred Income Taxes DeferredFederalIncomeTaxExpenseBenefitRemeasurementofDeferredIncomeTaxes	13000000.0	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	21700000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	11000000.0	USD
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	15800000	USD
CY2019	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-600000	USD
CY2018	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-600000	USD
CY2017	us-gaap	Deferred Other Tax Expense Benefit DeferredOtherTaxExpenseBenefit	-500000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-6700000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-15800000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	14400000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-6600000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-15500000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	14700000	USD
CY2017	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.35
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.21
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	178900000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	158600000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	186900000	USD
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Files In Submission

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$ALE
ALLETE INC Stock $ale

2019 Q4 Form 10-K Financial Statement

#000006675620000016 Filed on February 13, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE ALLETE INC Stock $ale

2019 Q4 Form 10-K Financial Statement

#000006675620000016 Filed on February 13, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$ALE
ALLETE INC Stock $ale