$WEC
WEC ENERGY GROUP, INC. Stock $wec

$wec Overview Financials Valuation SEC Filings Company Website

2020 Q4 Form 10-K Financial Statement

#000010781521000079 Filed on February 25, 2021

Income Statement

Concept	2020 Q4	2020 Q3	2020 Q2
Revenue	$1.933B	$1.651B	$1.549B
YoY Change	-0.72%	2.67%	-2.61%
Cost Of Revenue	$657.5M	$482.8M	$444.5M
YoY Change	0.77%	-0.31%	-9.64%
Gross Profit	$1.276B	$1.168B	$1.104B
YoY Change	-1.47%	3.96%	0.54%
Gross Profit Margin	65.99%	70.76%	71.3%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$249.3M	$245.0M	$242.5M
YoY Change	5.55%	4.79%	5.48%
% of Gross Profit	19.54%	20.97%	21.96%
Operating Expenses	$905.4M	$798.0M	$765.4M
YoY Change	1.57%	-1.82%	-2.34%
Operating Profit	$370.5M	$370.2M	$338.8M
YoY Change	2.04%	19.07%	7.69%
Interest Expense	-$66.60M	$122.0M	$124.4M
YoY Change	-49.0%	-3.02%	0.24%
% of Operating Profit	-17.98%	32.96%	36.72%
Other Income/Expense, Net	$11.30M	-$56.20M	-$42.90M
YoY Change	140.43%	-13.94%	-32.55%
Pretax Income	$276.8M	$314.0M	$295.9M
YoY Change	-0.32%	27.85%	17.89%
Income Tax	$37.20M	$46.90M	$53.80M
% Of Pretax Income	13.44%	14.94%	18.18%
Net Earnings	$239.0M	$267.1M	$242.1M
YoY Change	-2.01%	14.0%	2.67%
Net Earnings / Revenue	12.36%	16.18%	15.63%
Basic Earnings Per Share	$0.76	$0.85	$0.77
Diluted Earnings Per Share	$0.76	$0.84	$0.76
COMMON SHARES
Basic Shares Outstanding		315.4M shares	315.4M shares
Diluted Shares Outstanding		316.5M shares	316.5M shares

Balance Sheet

Concept	2020 Q4	2020 Q3	2020 Q2
SHORT-TERM ASSETS
Cash & Short-Term Investments	$25.00M	$13.00M	$13.00M
YoY Change	-34.21%	-35.0%	-65.79%
Cash & Equivalents	$24.80M	$13.10M	$13.30M
Short-Term Investments
Other Short-Term Assets	$63.40M	$59.40M	$64.20M
YoY Change	-6.76%	-27.38%	-20.05%
Inventory	$529.0M	$573.0M	$468.0M
Prepaid Expenses	$263.4M	$169.5M	$210.3M
Receivables	$1.203B	$911.8M	$957.9M
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$2.083B	$1.727B	$1.713B
YoY Change	-0.51%	-2.58%	-6.81%
LONG-TERM ASSETS
Property, Plant & Equipment	$25.71B	$24.55B	$24.17B
YoY Change	8.84%	6.58%	7.26%
Goodwill	$3.053B	$3.053B	$3.053B
YoY Change	0.0%	0.0%	0.0%
Intangibles
YoY Change
Long-Term Investments	$1.764B	$1.750B	$1.745B
YoY Change	2.51%	1.74%	2.84%
Other Assets	$295.6M	$877.7M	$848.9M
YoY Change	-69.14%	10.26%	5.65%
Total Long-Term Assets	$34.95B	$33.69B	$33.33B
YoY Change	6.35%	3.34%	3.84%
TOTAL ASSETS
Total Short-Term Assets	$2.083B	$1.727B	$1.713B
Total Long-Term Assets	$34.95B	$33.69B	$33.33B
Total Assets	$37.03B	$35.42B	$35.04B
YoY Change	5.94%	3.04%	3.26%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$880.7M	$751.3M	$696.6M
YoY Change	-3.02%	-2.3%	-2.66%
Accrued Expenses	$174.0M	$174.0M	$162.0M
YoY Change	-14.71%	1.75%	-1.22%
Deferred Revenue
YoY Change
Short-Term Debt	$1.777B	$771.0M	$1.212B
YoY Change	113.88%	12.39%	-4.08%
Long-Term Debt Due	$777.7M	$596.0M	$895.0M
YoY Change	13.22%	-14.0%	16.69%
Total Short-Term Liabilities	$4.148B	$2.840B	$3.485B
YoY Change	30.33%	0.77%	3.65%
LONG-TERM LIABILITIES
Long-Term Debt	$11.67B	$11.65B	$10.72B
YoY Change	4.49%	6.93%	8.07%
Other Long-Term Liabilities	$1.229B	$1.129B	$1.093B
YoY Change	8.9%	1.09%	-1.21%
Total Long-Term Liabilities	$22.22B	$22.02B	$21.06B
YoY Change	3.27%	3.04%	3.14%
TOTAL LIABILITIES
Total Short-Term Liabilities	$4.148B	$2.840B	$3.485B
Total Long-Term Liabilities	$22.22B	$22.02B	$21.06B
Total Liabilities	$26.37B	$24.86B	$24.55B
YoY Change	6.76%	2.78%	3.21%
SHAREHOLDERS EQUITY
Retained Earnings	$6.330B	$6.290B	$6.223B
YoY Change	6.78%	7.16%	6.89%
Common Stock	$4.147B	$4.167B	$4.168B
YoY Change	-1.02%	130118.75%	130156.25%
Preferred Stock
YoY Change
Treasury Stock (at cost)
YoY Change
Treasury Stock Shares
Shareholders Equity	$10.50B	$10.48B	$10.41B
YoY Change
Total Liabilities & Shareholders Equity	$37.03B	$35.42B	$35.04B
YoY Change	5.94%	3.04%	3.26%

Cashflow Statement

Concept	2020 Q4	2020 Q3	2020 Q2
OPERATING ACTIVITIES
Net Income	$239.0M	$267.1M	$242.1M
YoY Change	-2.01%	14.0%	2.67%
Depreciation, Depletion And Amortization	$249.3M	$245.0M	$242.5M
YoY Change	5.55%	4.79%	5.48%
Cash From Operating Activities	$246.3M	$570.1M	$689.1M
YoY Change	-51.21%	3.75%	24.05%
INVESTING ACTIVITIES
Capital Expenditures	$620.1M	$581.5M	$541.1M
YoY Change	-17.24%	-11.4%	9.0%
Acquisitions
YoY Change
Other Investing Activities	-$623.6M	$24.60M	-$2.100M
YoY Change	5518.02%	-308.47%	-105.74%
Cash From Investing Activities	-$1.244B	-$556.9M	-$543.2M
YoY Change	63.56%	-16.64%	18.14%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net
YoY Change
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	1.009B	-14.40M	-149.2M
YoY Change	271.84%	-115.24%	58.55%
NET CHANGE
Cash From Operating Activities	246.3M	570.1M	689.1M
Cash From Investing Activities	-1.244B	-556.9M	-543.2M
Cash From Financing Activities	1.009B	-14.40M	-149.2M
Net Change In Cash	11.40M	-1.200M	-3.300M
YoY Change	-27.39%	-95.02%	-306.25%
FREE CASH FLOW
Cash From Operating Activities	$246.3M	$570.1M	$689.1M
Capital Expenditures	$620.1M	$581.5M	$541.1M
Free Cash Flow	-$373.8M	-$11.40M	$148.0M
YoY Change	52.88%	-89.33%	150.42%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000783325
CY2020	dei	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	231 West Michigan Street
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Type DocumentType	10-K
CY2020	dei	Document Annual Report DocumentAnnualReport	true
CY2020	dei	Document Period End Date DocumentPeriodEndDate	2020-12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-09057
CY2020	dei	Entity Registrant Name EntityRegistrantName	WEC ENERGY GROUP, INC.
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	39-1391525
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	WI
CY2020	dei	Entity Address Address Line2 EntityAddressAddressLine2	P.O. Box 1331
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Milwaukee
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	WI
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	53201
CY2020	dei	City Area Code CityAreaCode	414
CY2020	dei	Local Phone Number LocalPhoneNumber	221-2345
CY2020	dei	Security12b Title Security12bTitle	Common Stock, $.01 Par Value
CY2020	dei	Trading Symbol TradingSymbol	WEC
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2020	dei	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Entity Filer Category EntityFilerCategory	Large Accelerated Filer
CY2020	dei	Entity Small Business EntitySmallBusiness	false
CY2020	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2020	dei	Icfr Auditor Attestation Flag IcfrAuditorAttestationFlag	true
CY2020	dei	Entity Shell Company EntityShellCompany	false
CY2020Q2	dei	Entity Public Float EntityPublicFloat	27600000000	USD
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	315434531	shares
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CY2020Q4	us-gaap	Deferred Revenue Noncurrent DeferredRevenueNoncurrent	412200000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	3992800000	USD
CY2020Q4	us-gaap	Accrued Environmental Loss Contingencies Noncurrent AccruedEnvironmentalLossContingenciesNoncurrent	532900000	USD
CY2019Q4	us-gaap	Deferred Revenue Noncurrent DeferredRevenueNoncurrent	497100000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	3928100000	USD
CY2019Q4	us-gaap	Accrued Environmental Loss Contingencies Noncurrent AccruedEnvironmentalLossContingenciesNoncurrent	589200000	USD
CY2020Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	327000000.0	USD
CY2019Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	326200000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1229400000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1128900000	USD
CY2020Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	22217500000	USD
CY2019Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	21514500000	USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	0.01
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	325000000	shares
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	3200000	USD
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	3200000	USD
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	325000000	shares
CY2019Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	315434531	shares
CY2020Q4	us-gaap	Common Stock Shares Outstanding CommonStockSharesOutstanding	315434531	shares
CY2020Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	4143700000	USD
CY2019Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	4186600000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	6329600000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	5927700000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-6800000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-4100000	USD
CY2020Q4	wec	Total Common Shareholders Equity TotalCommonShareholdersEquity	10469700000	USD
CY2019Q4	wec	Total Common Shareholders Equity TotalCommonShareholdersEquity	10113400000	USD
CY2020Q4	us-gaap	Preferred Stock Value PreferredStockValue	30400000	USD
CY2019Q4	us-gaap	Preferred Stock Value PreferredStockValue	30400000	USD
CY2020Q4	us-gaap	Other Minority Interests OtherMinorityInterests	162400000	USD
CY2019Q4	us-gaap	Other Minority Interests OtherMinorityInterests	110800000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	37028100000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	34951800000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	1201400000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	1134700000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	1060500000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	975900000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	926300000	USD
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	845800000	USD
CY2020	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	209400000	USD
CY2019	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	162900000	USD
CY2018	us-gaap	Deferred Income Taxes And Tax Credits DeferredIncomeTaxesAndTaxCredits	297300000	USD
CY2020	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	113200000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	65900000	USD
CY2018	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	77600000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	29100000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	2900000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments Net Of Dividends Or Distributions IncomeLossFromEquityMethodInvestmentsNetOfDividendsOrDistributions	18600000	USD
CY2020	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-16100000	USD
CY2019	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-98200000	USD
CY2018	us-gaap	Increase Decrease In Accounts And Other Receivables IncreaseDecreaseInAccountsAndOtherReceivables	-23500000	USD
CY2020	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	-21200000	USD
CY2019	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	1500000	USD
CY2018	us-gaap	Increase Decrease In Inventories IncreaseDecreaseInInventories	8800000	USD
CY2020	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	-13400000	USD
CY2019	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	7100000	USD
CY2018	us-gaap	Increase Decrease In Other Current Assets IncreaseDecreaseInOtherCurrentAssets	10000000.0	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-61300000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	1500000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	110600000	USD
CY2020	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-41200000	USD
CY2019	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	78700000	USD
CY2020	us-gaap	Payments To Acquire Business Two Net Of Cash Acquired PaymentsToAcquireBusinessTwoNetOfCashAcquired	0	USD
CY2018	us-gaap	Increase Decrease In Other Current Liabilities IncreaseDecreaseInOtherCurrentLiabilities	-67600000	USD
CY2020	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	3400000	USD
CY2019	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	20600000	USD
CY2018	us-gaap	Other Operating Activities Cash Flow Statement OtherOperatingActivitiesCashFlowStatement	290400000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2196000000.0	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2345500000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	2445500000	USD
CY2020	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	2238800000	USD
CY2019	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	2260800000	USD
CY2018	us-gaap	Payments To Acquire Other Property Plant And Equipment PaymentsToAcquireOtherPropertyPlantAndEquipment	2115700000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	364600000	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
CY2020	us-gaap	Payments To Acquire Assets Investing Activities PaymentsToAcquireAssetsInvestingActivities	239900000	USD
CY2019	us-gaap	Payments To Acquire Assets Investing Activities PaymentsToAcquireAssetsInvestingActivities	0	USD
CY2018	us-gaap	Payments To Acquire Assets Investing Activities PaymentsToAcquireAssetsInvestingActivities	0	USD
CY2019	us-gaap	Payments To Acquire Business Two Net Of Cash Acquired PaymentsToAcquireBusinessTwoNetOfCashAcquired	268200000	USD
CY2018	us-gaap	Payments To Acquire Business Two Net Of Cash Acquired PaymentsToAcquireBusinessTwoNetOfCashAcquired	0	USD
CY2020	us-gaap	Payments To Acquire Business Three Net Of Cash Acquired PaymentsToAcquireBusinessThreeNetOfCashAcquired	0	USD
CY2019	us-gaap	Payments To Acquire Business Three Net Of Cash Acquired PaymentsToAcquireBusinessThreeNetOfCashAcquired	0	USD
CY2018	us-gaap	Payments To Acquire Business Three Net Of Cash Acquired PaymentsToAcquireBusinessThreeNetOfCashAcquired	162900000	USD
CY2020	wec	Payments To Acquire Business Five PaymentsToAcquireBusinessFive	0	USD
CY2019	wec	Payments To Acquire Business Five PaymentsToAcquireBusinessFive	0	USD
CY2018	wec	Payments To Acquire Business Five PaymentsToAcquireBusinessFive	77100000	USD
CY2020	wec	Payments To Acquire Business Four PaymentsToAcquireBusinessFour	0	USD
CY2019	wec	Payments To Acquire Business Four PaymentsToAcquireBusinessFour	0	USD
CY2018	wec	Payments To Acquire Business Four PaymentsToAcquireBusinessFour	61400000	USD
CY2020	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	21200000	USD
CY2019	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	52600000	USD
CY2018	us-gaap	Payments To Acquire Interest In Subsidiaries And Affiliates PaymentsToAcquireInterestInSubsidiariesAndAffiliates	53500000	USD
CY2020	us-gaap	Proceeds From Sales Of Business Affiliate And Productive Assets ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets	20300000	USD
CY2019	us-gaap	Proceeds From Sales Of Business Affiliate And Productive Assets ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets	37600000	USD
CY2018	us-gaap	Proceeds From Sales Of Business Affiliate And Productive Assets ProceedsFromSalesOfBusinessAffiliateAndProductiveAssets	12100000	USD
CY2020	us-gaap	Proceeds From Sale Of Restricted Investments ProceedsFromSaleOfRestrictedInvestments	56200000	USD
CY2019	us-gaap	Proceeds From Sale Of Restricted Investments ProceedsFromSaleOfRestrictedInvestments	200000	USD
CY2018	us-gaap	Proceeds From Sale Of Restricted Investments ProceedsFromSaleOfRestrictedInvestments	118600000	USD
CY2020	us-gaap	Payments To Acquire Restricted Investments PaymentsToAcquireRestrictedInvestments	37800000	USD
CY2019	us-gaap	Payments To Acquire Restricted Investments PaymentsToAcquireRestrictedInvestments	0	USD
CY2018	us-gaap	Payments To Acquire Restricted Investments PaymentsToAcquireRestrictedInvestments	65000000.0	USD
CY2020	us-gaap	Proceeds From Collection Of Other Receivables ProceedsFromCollectionOfOtherReceivables	1100000	USD
CY2019	us-gaap	Proceeds From Collection Of Other Receivables ProceedsFromCollectionOfOtherReceivables	32400000	USD
CY2018	us-gaap	Proceeds From Collection Of Other Receivables ProceedsFromCollectionOfOtherReceivables	0	USD
CY2020	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	23200000	USD
CY2019	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	0	USD
CY2018	us-gaap	Proceeds From Insurance Settlement Investing Activities ProceedsFromInsuranceSettlementInvestingActivities	0	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	5300000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-16500000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-20500000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2806800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2494900000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-2384400000	USD
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	43800000	USD
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	67000000.0	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	29100000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	99200000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	140100000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	72400000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	798000000.0	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	744500000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	697300000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	2373600000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1895000000.0	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1740000000.0	USD
CY2020	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	1767000000.0	USD
CY2019	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	360100000	USD
CY2018	us-gaap	Repayments Of Long Term Debt RepaymentsOfLongTermDebt	953300000	USD
CY2020	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	340000000.0	USD
CY2019	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	0	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-5700000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	601100000	USD
CY2018	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	0	USD
CY2020	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	606100000	USD
CY2019	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-609300000	USD
CY2018	us-gaap	Proceeds From Repayments Of Short Term Debt Maturing In Three Months Or Less ProceedsFromRepaymentsOfShortTermDebtMaturingInThreeMonthsOrLess	-4500000	USD
CY2020	wec	Payments For Debt Extinguishment And Issuance Costs PaymentsForDebtExtinguishmentAndIssuanceCosts	55800000	USD
CY2019	wec	Payments For Debt Extinguishment And Issuance Costs PaymentsForDebtExtinguishmentAndIssuanceCosts	12500000	USD
CY2018	wec	Payments For Debt Extinguishment And Issuance Costs PaymentsForDebtExtinguishmentAndIssuanceCosts	9500000	USD
CY2020	us-gaap	Payments For Repurchase Of Redeemable Noncontrolling Interest PaymentsForRepurchaseOfRedeemableNoncontrollingInterest	31000000.0	USD
CY2019	us-gaap	Payments For Repurchase Of Redeemable Noncontrolling Interest PaymentsForRepurchaseOfRedeemableNoncontrollingInterest	0	USD
CY2018	us-gaap	Payments For Repurchase Of Redeemable Noncontrolling Interest PaymentsForRepurchaseOfRedeemableNoncontrollingInterest	0	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-11400000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-9900000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-63800000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	85600000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	26400000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-9700000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	87500000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	82300000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	146100000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	58600000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	72600000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	82300000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	146100000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.21
CY2019	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.36
CY2020	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	2.53
CY2020	us-gaap	Use Of Estimates UseOfEstimates	We prepare our financial statements in conformity with GAAP. We make estimates and assumptions that affect the reported amounts of assets and liabilities, the disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results may differ from these estimates.
CY2020	wec	Maximum Term Of Original Maturity To Classify Instrument As Cash Equivalent MaximumTermOfOriginalMaturityToClassifyInstrumentAsCashEquivalent	three months
CY2020Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	224900000	USD
CY2019Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	227700000	USD
CY2020Q4	us-gaap	Inventory Raw Materials And Supplies Net Of Reserves InventoryRawMaterialsAndSuppliesNetOfReserves	218100000	USD
CY2019Q4	us-gaap	Inventory Raw Materials And Supplies Net Of Reserves InventoryRawMaterialsAndSuppliesNetOfReserves	234200000	USD
CY2020Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	85600000	USD
CY2019Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	87900000	USD
CY2020Q4	us-gaap	Energy Related Inventory EnergyRelatedInventory	528600000	USD
CY2019Q4	us-gaap	Energy Related Inventory EnergyRelatedInventory	549800000	USD
CY2020Q4	us-gaap	Percentage Of Lifo Inventory PercentageOfLIFOInventory	0.22
CY2019Q4	us-gaap	Percentage Of Lifo Inventory PercentageOfLIFOInventory	0.19
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	8000000.0	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	5900000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	6900000	USD
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	20900000	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	14400000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	15200000	USD
CY2020Q4	us-gaap	Hosting Arrangement Service Contract Implementation Cost Capitalized After Accumulated Amortization HostingArrangementServiceContractImplementationCostCapitalizedAfterAccumulatedAmortization	1800000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized	34300000	shares
CY2020	us-gaap	Guarantees Indemnifications And Warranties Policies GuaranteesIndemnificationsAndWarrantiesPolicies	We follow the guidance of the Guarantees Topic of the FASB ASC, which requires, under certain circumstances, that the guarantor recognize a liability for the fair value of the obligation undertaken in issuing the guarantee at its inception.
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	The geographic concentration of our customers did not contribute significantly to our overall exposure to credit risk. We periodically review customers' credit ratings, financial statements, and historical payment performance and require them to provide collateral or other security as needed. Credit risk exposure at WE, WPS, WG, PGL, and NSG is mitigated by their recovery mechanisms for uncollectible expense discussed in Note 1(d), Operating Revenues. As a result, we did not have any significant concentrations of credit risk at December 31, 2020. In addition, there were no customers that accounted for more than 10% of our revenues for the year ended December 31, 2020
CY2020	us-gaap	Revenues Revenues	7241700000	USD
CY2019	us-gaap	Revenues Revenues	7523100000	USD
CY2018	us-gaap	Revenues Revenues	7679500000	USD
CY2020Q4	us-gaap	Accounts Receivable Gross AccountsReceivableGross	1422900000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	220100000	USD
CY2020Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	1202800000	USD
CY2020Q4	wec	Accounts Receivable Past Due Greaterthan90 Days AccountsReceivablePastDueGreaterthan90Days	122800000	USD
CY2020Q4	wec	Percentofaccountsreceivablepastduegreaterthan90dayswithregulatorymechanismstocollect Percentofaccountsreceivablepastduegreaterthan90dayswithregulatorymechanismstocollect	0.955
CY2020Q4	wec	Amountofnetaccountsreceivablewithregulatoryprotections Amountofnetaccountsreceivablewithregulatoryprotections	679400000	USD
CY2020Q4	wec	Percentofnetaccountsreceivablewithregulatoryprotections Percentofnetaccountsreceivablewithregulatoryprotections	0.565
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	140000000.0	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	102900000	USD
CY2020	us-gaap	Increase Decrease In Regulatory Assets And Liabilities IncreaseDecreaseInRegulatoryAssetsAndLiabilities	55200000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	132300000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	54400000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	220100000	USD
CY2020Q4	us-gaap	Regulatory Assets RegulatoryAssets	3544100000	USD
CY2019Q4	us-gaap	Regulatory Assets RegulatoryAssets	3527600000	USD
CY2020Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	20000000.0	USD
CY2019Q4	us-gaap	Regulatory Assets Current RegulatoryAssetsCurrent	20900000	USD
CY2020Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	3524100000	USD
CY2019Q4	us-gaap	Regulatory Assets Noncurrent RegulatoryAssetsNoncurrent	3506700000	USD
CY2020Q4	us-gaap	Regulatory Assets RegulatoryAssets	3544100000	USD
CY2019Q4	us-gaap	Regulatory Assets RegulatoryAssets	3527600000	USD
CY2020Q4	us-gaap	Public Utilities Amount Of Allowance For Earnings On Equity Capitalized For Rate Making Purposes PublicUtilitiesAmountOfAllowanceForEarningsOnEquityCapitalizedForRateMakingPurposes	34200000	USD
CY2019Q4	us-gaap	Public Utilities Amount Of Allowance For Earnings On Equity Capitalized For Rate Making Purposes PublicUtilitiesAmountOfAllowanceForEarningsOnEquityCapitalizedForRateMakingPurposes	24300000	USD
CY2020Q4	us-gaap	Remaining Amounts Of Regulatory Assets For Which No Return On Investment During Recovery Period Is Provided RemainingAmountsOfRegulatoryAssetsForWhichNoReturnOnInvestmentDuringRecoveryPeriodIsProvided	238800000	USD
CY2020Q4	wec	Remaining Amounts Of Regulatory Assets Earning Short Term Interest Rate Return On Investment RemainingAmountsOfRegulatoryAssetsEarningShortTermInterestRateReturnOnInvestment	9700000	USD
CY2020Q4	wec	Remaining Amounts Of Regulatory Assets Earning Long Term Interest Rate Return On Investment RemainingAmountsOfRegulatoryAssetsEarningLongTermInterestRateReturnOnInvestment	135600000	USD
CY2020Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	3979100000	USD
CY2019Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	4080400000	USD
CY2020Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	51000000.0	USD
CY2019Q4	us-gaap	Regulatory Liability Current RegulatoryLiabilityCurrent	87600000	USD
CY2020Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	3928100000	USD
CY2019Q4	us-gaap	Regulatory Liability Noncurrent RegulatoryLiabilityNoncurrent	3992800000	USD
CY2020Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	3979100000	USD
CY2019Q4	us-gaap	Regulatory Liabilities RegulatoryLiabilities	4080400000	USD
CY2018Q4	us-gaap	Restructuring Reserve RestructuringReserve	15700000	USD
CY2017Q4	us-gaap	Restructuring Reserve RestructuringReserve	29400000	USD
CY2017Q4	us-gaap	Restructuring Reserve RestructuringReserve	29400000	USD
CY2019Q4	us-gaap	Restructuring Reserve RestructuringReserve	2100000	USD
CY2020	us-gaap	Payments For Restructuring PaymentsForRestructuring	100000	USD
CY2019	us-gaap	Payments For Restructuring PaymentsForRestructuring	7200000	USD
CY2018	us-gaap	Payments For Restructuring PaymentsForRestructuring	10700000	USD
CY2020	us-gaap	Restructuring Reserve Accrual Adjustment1 RestructuringReserveAccrualAdjustment1	-1300000	USD
CY2019	us-gaap	Restructuring Reserve Accrual Adjustment1 RestructuringReserveAccrualAdjustment1	-6400000	USD
CY2018	us-gaap	Restructuring Reserve Accrual Adjustment1 RestructuringReserveAccrualAdjustment1	-3000000.0	USD
CY2020Q4	us-gaap	Restructuring Reserve RestructuringReserve	700000	USD
CY2019Q4	us-gaap	Restructuring Reserve RestructuringReserve	2100000	USD
CY2018Q4	us-gaap	Restructuring Reserve RestructuringReserve	15700000	USD
CY2019	wec	Asset Retirement Obligation Addition Revision Of Estimate AssetRetirementObligationAdditionRevisionOfEstimate	39100000	USD
CY2020	wec	Psb Building Repair And Restoration Costs In Other Operation And Maintenance Expense PSBBuildingRepairAndRestorationCostsInOtherOperationAndMaintenanceExpense	12500000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	25707400000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	23620100000	USD
CY2020Q4	wec	Costs Incurred For Repairs And Restorations CostsIncurredForRepairsAndRestorations	35200000	USD
CY2020	wec	Insurance Proceeds Received To Cover Damage To Psb Building InsuranceProceedsReceivedToCoverDamageToPSBBuilding	20000000.0	USD
CY2020Q4	wec	Receivable Recorded For Future Insurance Recoveries ReceivableRecordedForFutureInsuranceRecoveries	2700000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	483500000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	461400000	USD
CY2017Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	573700000	USD
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	20700000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	22100000	USD
CY2018	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	28000000.0	USD
CY2020	wec	Asset Retirement Obligation Addition Revision Of Estimate AssetRetirementObligationAdditionRevisionOfEstimate	39700000	USD
CY2018	wec	Asset Retirement Obligation Addition Revision Of Estimate AssetRetirementObligationAdditionRevisionOfEstimate	-104500000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	30400000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	39100000	USD
CY2018	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	35800000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	513500000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	483500000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	461400000	USD
CY2020	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0	USD
CY2019	us-gaap	Goodwill Period Increase Decrease GoodwillPeriodIncreaseDecrease	0	USD
CY2020Q4	us-gaap	Goodwill Goodwill	3052800000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	3052800000	USD
CY2020Q4	us-gaap	Goodwill Impaired Accumulated Impairment Loss GoodwillImpairedAccumulatedImpairmentLoss	0	USD
CY2020Q3	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2019	us-gaap	Indefinite Lived Intangible Assets Period Increase Decrease IndefiniteLivedIntangibleAssetsPeriodIncreaseDecrease	0	USD
CY2020	us-gaap	Indefinite Lived Intangible Assets Period Increase Decrease IndefiniteLivedIntangibleAssetsPeriodIncreaseDecrease	0	USD
CY2020	wec	Period Of Amortization PeriodOfAmortization	P5Y
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	35700000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	50200000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	36100000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	9800000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	13800000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	9900000	USD
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1800000	shares
CY2020Q4	wec	Juniornotesminimuminterestdeferralpaymentperiodinperiods Juniornotesminimuminterestdeferralpaymentperiodinperiods	1	period
CY2020	wec	Maximuminterestpaymentdeferralperiod Maximuminterestpaymentdeferralperiod	P10Y
CY2020Q4	us-gaap	Amount Of Restricted Net Assets For Consolidated And Unconsolidated Subsidiaries AmountOfRestrictedNetAssetsForConsolidatedAndUnconsolidatedSubsidiaries	8600000000	USD
CY2020Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	386000000	USD
CY2020	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	0	shares
CY2019	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	0	shares
CY2018	us-gaap	Stock Issued During Period Shares New Issues StockIssuedDuringPeriodSharesNewIssues	0	shares
CY2020	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1000000.0	shares
CY2018	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	1100000	shares
CY2020	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	99200000	USD
CY2019	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	140100000	USD
CY2018	us-gaap	Stock Repurchased During Period Value StockRepurchasedDuringPeriodValue	72400000	USD
CY2020Q1	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.6325
CY2020Q2	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.6325
CY2020Q3	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.6325
CY2020Q4	us-gaap	Common Stock Dividends Per Share Declared CommonStockDividendsPerShareDeclared	0.6325
CY2020Q4	us-gaap	Preferred Stock Value PreferredStockValue	30400000	USD
CY2019Q4	us-gaap	Preferred Stock Value PreferredStockValue	30400000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	3140000000.0	USD
CY2020Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	1360800000	USD
CY2020Q4	wec	Numberofextensionsavailableonacreditfacility Numberofextensionsavailableonacreditfacility	2	extension
CY2020	wec	Lengthofcreditfacilityextension Lengthofcreditfacilityextension	P1Y
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	12529200000	USD
CY2019Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	11922500000	USD
CY2020Q4	wec	Integrys Fair Value Adjustment Long Term Debt IntegrysFairValueAdjustmentLongTermDebt	8400000	USD
CY2019Q4	wec	Integrys Fair Value Adjustment Long Term Debt IntegrysFairValueAdjustmentLongTermDebt	14300000	USD
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	65200000	USD
CY2019Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	52900000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	21900000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	25600000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	12450500000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	11858300000	USD
CY2020Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	777700000	USD
CY2019Q4	us-gaap	Long Term Debt Current LongTermDebtCurrent	686900000	USD
CY2020Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	11672800000	USD
CY2019Q4	us-gaap	Long Term Debt Noncurrent LongTermDebtNoncurrent	11171400000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	63400000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	45900000	USD
CY2020Q4	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-27900000	USD
CY2020Q4	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-10500000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	777700000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	777700000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	83300000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	784900000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	613700000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	1156700000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	9112900000	USD
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	12529200000	USD
CY2018	wec	Capital Lease Expense Under Asc840 CapitalLeaseExpenseUnderASC840	7700000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	5400000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	6300000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	4900000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	2500000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	3300000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	5500000	USD
CY2018	us-gaap	Operating Lease Cost OperatingLeaseCost	5600000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	300000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	600000	USD
CY2018	us-gaap	Short Term Lease Cost ShortTermLeaseCost	1500000	USD
CY2020	us-gaap	Lease Cost LeaseCost	14500000	USD
CY2019	us-gaap	Lease Cost LeaseCost	14300000	USD
CY2018	us-gaap	Lease Cost LeaseCost	14800000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	2500000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	6300000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	4900000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	22800000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	27200000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	3300000	USD
CY2018	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	7700000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	6700000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	6000000.0	USD
CY2018	us-gaap	Operating Lease Payments OperatingLeasePayments	6500000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	0	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	49000000.0	USD
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P41Y6M
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P31Y6M
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P13Y
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P12Y10M24D
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.049
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.067
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.034
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.044
CY2020Q4	us-gaap	Property Plant And Equipment Other Net PropertyPlantAndEquipmentOtherNet	57000000.0	USD
CY2019Q4	us-gaap	Property Plant And Equipment Other Net PropertyPlantAndEquipmentOtherNet	40600000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	20700000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	41400000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	4500000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	10600000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	4400000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	5400000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	4500000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	1600000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	4300000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	1600000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	63400000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	8100000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	55300000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	3800000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	1600000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	24500000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	130300000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	46000000.0	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	151100000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	10200000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	87700000	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	49200000	USD
CY2020	wec	Effective Income Tax Rate Reconciliation Allowance For Funds Used During Construction Capitalized Cost Of Equity EffectiveIncomeTaxRateReconciliationAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	0.003
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-37900000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	-127500000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	182200000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	167700000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	300100000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	3500000	USD
CY2019	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	4800000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	2800000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	227900000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	125000000.0	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	169800000	USD
CY2020	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	299900000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	264400000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	258100000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	90500000	USD
CY2020	wec	Effective Income Tax Rate Reconciliation State And Local Income Taxes Net Of Federal Tax Benefit EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxesNetOfFederalTaxBenefit	0.063
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	80400000	USD
CY2019	wec	Effective Income Tax Rate Reconciliation State And Local Income Taxes Net Of Federal Tax Benefit EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxesNetOfFederalTaxBenefit	0.064
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	71800000	USD
CY2018	wec	Effective Income Tax Rate Reconciliation State And Local Income Taxes Net Of Federal Tax Benefit EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxesNetOfFederalTaxBenefit	0.058
CY2020	wec	Effective Income Tax Reconciliation Taxexpensebenefitfederalexcessdeferredtaxamortization Wisconsinunprotected EffectiveIncomeTaxReconciliationTaxexpensebenefitfederalexcessdeferredtaxamortizationWisconsinunprotected	-57600000	USD
CY2020	wec	Effective Income Taxreconciliation Federalexcessdeferredtaxamortization Wi Unprotectedpercent EffectiveIncomeTaxreconciliationFederalexcessdeferredtaxamortizationWIUnprotectedpercent	-0.040
CY2019	wec	Effective Income Tax Reconciliation Taxexpensebenefitfederalexcessdeferredtaxamortization Wisconsinunprotected EffectiveIncomeTaxReconciliationTaxexpensebenefitfederalexcessdeferredtaxamortizationWisconsinunprotected	0	USD
CY2019	wec	Effective Income Taxreconciliation Federalexcessdeferredtaxamortization Wi Unprotectedpercent EffectiveIncomeTaxreconciliationFederalexcessdeferredtaxamortizationWIUnprotectedpercent	0
CY2018	wec	Effective Income Tax Reconciliation Taxexpensebenefitfederalexcessdeferredtaxamortization Wisconsinunprotected EffectiveIncomeTaxReconciliationTaxexpensebenefitfederalexcessdeferredtaxamortizationWisconsinunprotected	0	USD
CY2018	wec	Effective Income Taxreconciliation Federalexcessdeferredtaxamortization Wi Unprotectedpercent EffectiveIncomeTaxreconciliationFederalexcessdeferredtaxamortizationWIUnprotectedpercent	0
CY2020	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	51500000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Other EffectiveIncomeTaxRateReconciliationTaxCreditsOther	0.036
CY2019	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	34100000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Other EffectiveIncomeTaxRateReconciliationTaxCreditsOther	0.027
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Other IncomeTaxReconciliationTaxCreditsOther	12100000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Other EffectiveIncomeTaxRateReconciliationTaxCreditsOther	0.010
CY2020	wec	Federalexcessamortizationamount Federalexcessamortizationamount	-36700000	USD
CY2020	wec	Federalexcessamortizationeffectivetaxrate Federalexcessamortizationeffectivetaxrate	-0.026
CY2019	wec	Federalexcessamortizationamount Federalexcessamortizationamount	-34900000	USD
CY2019	wec	Federalexcessamortizationeffectivetaxrate Federalexcessamortizationeffectivetaxrate	-0.028
CY2018	wec	Federalexcessamortizationamount Federalexcessamortizationamount	-16800000	USD
CY2018	wec	Federalexcessamortizationeffectivetaxrate Federalexcessamortizationeffectivetaxrate	-0.014
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-12300000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.009
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-15800000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.013
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Share Based Compensation Excess Tax Benefit Amount EffectiveIncomeTaxRateReconciliationShareBasedCompensationExcessTaxBenefitAmount	-5900000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Share Based Compensation Cost EffectiveIncomeTaxRateReconciliationNondeductibleExpenseShareBasedCompensationCost	-0.005
CY2020	wec	Income Tax Reconciliation Allowance For Funds Used During Construction Capitalized Cost Of Equity IncomeTaxReconciliationAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	4400000	USD
CY2020	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	3500000	USD
CY2018	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	2800000	USD
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	0.002
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	0.002
CY2019	us-gaap	Income Tax Reconciliation Tax Credits Investment IncomeTaxReconciliationTaxCreditsInvestment	4800000	USD
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	0.004
CY2019	wec	Income Tax Reconciliation Allowance For Funds Used During Construction Capitalized Cost Of Equity IncomeTaxReconciliationAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	3000000.0	USD
CY2019	wec	Effective Income Tax Rate Reconciliation Allowance For Funds Used During Construction Capitalized Cost Of Equity EffectiveIncomeTaxRateReconciliationAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	0.002
CY2018	wec	Income Tax Reconciliation Allowance For Funds Used During Construction Capitalized Cost Of Equity IncomeTaxReconciliationAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	3200000	USD
CY2018	wec	Effective Income Tax Rate Reconciliation Allowance For Funds Used During Construction Capitalized Cost Of Equity EffectiveIncomeTaxRateReconciliationAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	0.003
CY2020	wec	Taxrepairsamount Taxrepairsamount	3300000	USD
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CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	4653900000	USD
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	4059800000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	3769300000	USD
CY2020Q4	wec	Balanceof Tax Benefit Carryforward BalanceofTaxBenefitCarryforward	88800000	USD
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CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	2300000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17900000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	20000000.0	USD
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CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	1900000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	100000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Increases Resulting From Current Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromCurrentPeriodTaxPositions	200000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	7700000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	4200000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	11900000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	17900000	USD
CY2020Q4	wec	Deferred Tax Assets Uncertainty In Income Taxes DeferredTaxAssetsUncertaintyInIncomeTaxes	1900000	USD
CY2019Q4	wec	Deferred Tax Assets Uncertainty In Income Taxes DeferredTaxAssetsUncertaintyInIncomeTaxes	2000000.0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	10100000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits That Would Impact Effective Tax Rate UnrecognizedTaxBenefitsThatWouldImpactEffectiveTaxRate	15900000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	-300000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	100000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Expense UnrecognizedTaxBenefitsInterestOnIncomeTaxesExpense	500000	USD
CY2020	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	USD
CY2018	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	USD
CY2019	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Expense UnrecognizedTaxBenefitsIncomeTaxPenaltiesExpense	0	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	500000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Interest On Income Taxes Accrued UnrecognizedTaxBenefitsInterestOnIncomeTaxesAccrued	800000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits Income Tax Penalties Accrued UnrecognizedTaxBenefitsIncomeTaxPenaltiesAccrued	0	USD
CY2020	wec	Unrecognizedtaxbenefitsdecreaseresultingfromstatuteoflimitations Unrecognizedtaxbenefitsdecreaseresultingfromstatuteoflimitations	7500000	USD
CY2020	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	6300000	USD
CY2019	us-gaap	Equity Securities Fv Ni Unrealized Gain Loss EquitySecuritiesFvNiUnrealizedGainLoss	18700000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Settlements FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements	15400000	USD
CY2020Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	2400000	USD
CY2019Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	3100000	USD
CY2018Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	7400000	USD
CY2019Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	3100000	USD
CY2018Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	7400000	USD
CY2017Q4	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis With Unobservable Inputs FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisWithUnobservableInputs	4400000	USD
CY2020	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Purchases FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases	7600000	USD
CY2019	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Purchases FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases	12800000	USD
CY2018	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Purchases FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationPurchases	18400000	USD
CY2020	us-gaap	Fair Value Net Derivative Asset Liability Measured On Recurring Basis Unobservable Inputs Reconciliation Settlements FairValueNetDerivativeAssetLiabilityMeasuredOnRecurringBasisUnobservableInputsReconciliationSettlements	8300000	USD
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CY2019Q4	us-gaap	Derivative Instruments And Hedges DerivativeInstrumentsAndHedges	6700000	USD
CY2019Q4	wec	Derivative Instruments And Hedges Liabilities Gross Current DerivativeInstrumentsAndHedgesLiabilitiesGrossCurrent	24800000	USD
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CY2019Q4	us-gaap	Derivative Instruments And Hedges Noncurrent DerivativeInstrumentsAndHedgesNoncurrent	200000	USD
CY2019Q4	us-gaap	Derivative Instruments And Hedges Liabilities Noncurrent DerivativeInstrumentsAndHedgesLiabilitiesNoncurrent	4100000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	17900000	USD
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CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	6900000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	28900000	USD
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CY2019	us-gaap	Derivative Gain Loss On Derivative Net DerivativeGainLossOnDerivativeNet	-10800000	USD
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CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	18900000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	34400000	USD
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CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Asset Including Not Subject To Master Netting Arrangement DerivativeAssetFairValueGrossAssetIncludingNotSubjectToMasterNettingArrangement	6900000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Liability Including Not Subject To Master Netting Arrangement DerivativeLiabilityFairValueGrossLiabilityIncludingNotSubjectToMasterNettingArrangement	28900000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Gross Liability And Obligation To Return Cash Offset DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset	6900000	USD
CY2020Q4	us-gaap	Derivative Liability Fair Value Gross Asset And Right To Reclaim Cash Offset DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset	7700000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Liability And Obligation To Return Cash Offset DerivativeAssetFairValueGrossLiabilityAndObligationToReturnCashOffset	1400000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Asset And Right To Reclaim Cash Offset DerivativeLiabilityFairValueGrossAssetAndRightToReclaimCashOffset	21400000	USD
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CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	14400000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	5500000	USD
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CY2020	us-gaap	Interest Expense InterestExpense	493700000	USD
CY2019	us-gaap	Interest Expense InterestExpense	501500000	USD
CY2018	us-gaap	Interest Expense InterestExpense	445100000	USD
CY2020	us-gaap	Cash Flow Hedge Gain Loss To Be Reclassified Within Twelve Months CashFlowHedgeGainLossToBeReclassifiedWithinTwelveMonths	-5500000	USD
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CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	49700000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	50900000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	49300000	USD
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CY2020	us-gaap	Revenues Revenues	7241700000	USD
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CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	175800000	USD
CY2020	us-gaap	Interest Expense InterestExpense	493700000	USD
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CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	227900000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	1201400000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1199900000	USD
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CY2020Q4	us-gaap	Assets Assets	37028100000	USD
CY2019	us-gaap	Revenues Revenues	7523100000	USD
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CY2019	us-gaap	Interest Expense InterestExpense	501500000	USD
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CY2020Q4	us-gaap	Purchase Obligation PurchaseObligation	10979400000	USD
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CY2020	us-gaap	Gain Loss On Investments GainLossOnInvestments	12700000	USD
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CY2018	us-gaap	Gain Loss On Investments GainLossOnInvestments	-1800000	USD
CY2020	wec	Other Unclassified Nonoperating Income Expense OtherUnclassifiedNonoperatingIncomeExpense	4700000	USD
CY2020Q3	us-gaap	Revenues Revenues	1651000000.0	USD
CY2020Q4	us-gaap	Revenues Revenues	1933400000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	1706100000	USD
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CY2020Q1	us-gaap	Revenues Revenues	2108600000	USD
CY2020Q2	us-gaap	Revenues Revenues	1548700000	USD
CY2020	us-gaap	Revenues Revenues	7241700000	USD
CY2020Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	626600000	USD
CY2020Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	338800000	USD
CY2020Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	370200000	USD
CY2020Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	370500000	USD
CY2020Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	266800000	USD
CY2020Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	239000000.0	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1199900000	USD
CY2020Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.43
CY2020Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.77
CY2020Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.85
CY2020Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.80
CY2020Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.43
CY2020Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.76
CY2020Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.84
CY2020Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.76
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.79
CY2019Q1	us-gaap	Revenues Revenues	2377400000	USD
CY2019Q2	us-gaap	Revenues Revenues	1590200000	USD
CY2019Q3	us-gaap	Revenues Revenues	1608000000.0	USD
CY2019Q4	us-gaap	Revenues Revenues	1947500000	USD
CY2019	us-gaap	Revenues Revenues	7523100000	USD
CY2019Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	542800000	USD
CY2019Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	314600000	USD
CY2019Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	310900000	USD
CY2019Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	363100000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	1531400000	USD
CY2019Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	420100000	USD
CY2019Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	235700000	USD
CY2019Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	234300000	USD
CY2019Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	243900000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	1134000000.0	USD
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.33
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.75
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.74
CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.77
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	3.60
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.33
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.74
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.74
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.77
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	3.58
CY2019Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	140000000.0	USD
CY2020	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	102800000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	55300000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	77900000	USD
CY2020	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	-100000	USD
CY2020Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	220100000	USD
CY2018Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	149200000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	85800000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	11400000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	106400000	USD
CY2019	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	0	USD
CY2019Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	140000000.0	USD
CY2017Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	143200000	USD
CY2018	us-gaap	Valuation Allowances And Reserves Charged To Cost And Expense ValuationAllowancesAndReservesChargedToCostAndExpense	94700000	USD
CY2018	us-gaap	Valuation Allowances And Reserves Charged To Other Accounts ValuationAllowancesAndReservesChargedToOtherAccounts	-5500000	USD
CY2018	us-gaap	Valuation Allowances And Reserves Deductions ValuationAllowancesAndReservesDeductions	83200000	USD
CY2018	us-gaap	Valuation Allowances And Reserves Adjustments ValuationAllowancesAndReservesAdjustments	0	USD
CY2018Q4	us-gaap	Valuation Allowances And Reserves Balance ValuationAllowancesAndReservesBalance	149200000	USD

Files In Submission

Name	View Source	Status
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0000107815-21-000079.txt	Edgar Link	pending
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$WEC
WEC ENERGY GROUP, INC. Stock $wec

2020 Q4 Form 10-K Financial Statement

#000010781521000079 Filed on February 25, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WEC WEC ENERGY GROUP, INC. Stock $wec

2020 Q4 Form 10-K Financial Statement

#000010781521000079 Filed on February 25, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$WEC
WEC ENERGY GROUP, INC. Stock $wec