$SO
SOUTHERN CO Stock $so

$so Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 10-K Financial Statement

#000009212221000006 Filed on February 18, 2021

Income Statement

Concept	2019 Q4	2018 Q4	2018
Revenue	$4.914B	$5.337B	$23.50B
YoY Change	-7.93%	-5.19%	2.01%
Cost Of Revenue	$673.0M	$815.0M	$3.316B
YoY Change	-17.42%	-14.48%	11.39%
Gross Profit	$4.241B	$4.522B	$20.18B
YoY Change	-6.21%	-3.27%	0.62%
Gross Profit Margin	86.3%	84.73%	85.89%
Selling, General & Admin
YoY Change
% of Gross Profit
Research & Development
YoY Change
% of Gross Profit
Depreciation & Amortization	$817.0M	$902.0M	$3.549B
YoY Change	-9.42%	1.01%	2.66%
% of Gross Profit	19.26%	19.95%	17.59%
Operating Expenses	$3.568B	$3.913B	$14.97B
YoY Change	-8.82%	4.35%	3.98%
Operating Profit	$690.0M	$578.0M	$4.191B
YoY Change	19.38%	-21.79%	79.64%
Interest Expense	-$400.0M	-$416.0M	-$1.694B
YoY Change	-3.85%	-5.45%	6.68%
% of Operating Profit	-57.97%	-71.97%	-40.42%
Other Income/Expense, Net	$45.00M	-$42.00M	-$1.442B
YoY Change	-207.14%	-268.0%	13.99%
Pretax Income	$335.0M	$120.0M	$2.749B
YoY Change	179.17%	-62.96%	157.4%
Income Tax	-$74.00M	-$119.0M	$449.0M
% Of Pretax Income	-22.09%	-99.17%	16.33%
Net Earnings	$440.0M	$278.0M	$2.300B
YoY Change	58.27%	-43.95%	148.38%
Net Earnings / Revenue	8.95%	5.21%	9.79%
Basic Earnings Per Share	$0.42	$0.27	$2.18
Diluted Earnings Per Share	$0.42	$0.27	$2.17
COMMON SHARES
Basic Shares Outstanding			1.020B shares
Diluted Shares Outstanding			1.025B shares

Balance Sheet

Concept	2019 Q4	2018 Q4	2018
SHORT-TERM ASSETS
Cash & Short-Term Investments	$1.975B	$1.396B	$1.396B
YoY Change	41.48%	-34.46%	-34.46%
Cash & Equivalents	$1.975B	$1.396B	$1.396B
Short-Term Investments
Other Short-Term Assets	$188.0M	$162.0M	$2.388B
YoY Change	16.05%	161.29%	14.97%
Inventory	$2.388B	$2.394B	$2.394B
Prepaid Expenses	$314.0M	$432.0M
Receivables	$1.565B	$1.676B	$1.676B
Other Receivables	$1.245B	$1.729B	$1.729B
Total Short-Term Assets	$9.817B	$9.583B	$9.583B
YoY Change	2.44%	-4.86%	-4.86%
LONG-TERM ASSETS
Property, Plant & Equipment	$83.08B	$80.80B	$80.80B
YoY Change	2.83%	1.16%	1.16%
Goodwill	$5.280B	$5.315B
YoY Change	-0.66%	-15.2%
Intangibles	$536.0M	$613.0M
YoY Change	-12.56%	-29.78%
Long-Term Investments	$1.303B	$1.580B	$1.580B
YoY Change	-17.53%	4.43%	4.43%
Other Assets	$1.071B	$1.463B	$19.03B
YoY Change	-26.79%	-7.23%	53.35%
Total Long-Term Assets	$108.9B	$107.3B	$107.3B
YoY Change	1.45%	6.34%	6.34%
TOTAL ASSETS
Total Short-Term Assets	$9.817B	$9.583B	$9.583B
Total Long-Term Assets	$108.9B	$107.3B	$107.3B
Total Assets	$118.7B	$116.9B	$116.9B
YoY Change	1.53%	5.32%	5.32%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$2.115B	$2.580B	$3.436B
YoY Change	-18.02%	1.98%	11.52%
Accrued Expenses	$2.354B	$2.158B	$2.158B
YoY Change	9.08%	4.76%	4.76%
Deferred Revenue
YoY Change
Short-Term Debt	$2.055B	$2.915B	$2.915B
YoY Change	-29.5%	19.52%	19.52%
Long-Term Debt Due	$2.989B	$3.198B	$3.198B
YoY Change	-6.54%	-17.83%	-17.83%
Total Short-Term Liabilities	$12.55B	$14.29B	$14.29B
YoY Change	-12.18%	5.09%	5.09%
LONG-TERM LIABILITIES
Long-Term Debt	$41.80B	$40.74B	$40.74B
YoY Change	2.61%	-8.38%	-8.38%
Other Long-Term Liabilities	$609.0M	$465.0M	$17.17B
YoY Change	30.97%	-32.71%	60.01%
Total Long-Term Liabilities	$609.0M	$465.0M	$57.91B
YoY Change	30.97%	-32.71%	4.92%
TOTAL LIABILITIES
Total Short-Term Liabilities	$12.55B	$14.29B	$14.29B
Total Long-Term Liabilities	$609.0M	$465.0M	$57.91B
Total Liabilities	$86.65B	$87.58B	$91.90B
YoY Change	-1.07%	2.85%	6.23%
SHAREHOLDERS EQUITY
Retained Earnings	$10.88B	$8.706B
YoY Change	24.94%	-2.01%
Common Stock	$16.99B	$16.26B
YoY Change	4.51%	4.84%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$42.00M	$38.00M
YoY Change	10.53%	5.56%
Treasury Stock Shares	1.000M shares	1.000M shares
Shareholders Equity	$27.51B	$24.72B	$25.01B
YoY Change
Total Liabilities & Shareholders Equity	$118.7B	$116.9B	$116.9B
YoY Change	1.53%	5.32%	5.32%

Cashflow Statement

Concept	2019 Q4	2018 Q4	2018
OPERATING ACTIVITIES
Net Income	$440.0M	$278.0M	$2.300B
YoY Change	58.27%	-43.95%	148.38%
Depreciation, Depletion And Amortization	$817.0M	$902.0M	$3.549B
YoY Change	-9.42%	1.01%	2.66%
Cash From Operating Activities	$900.0M	$1.361B	$6.945B
YoY Change	-33.87%	19.18%	8.62%
INVESTING ACTIVITIES
Capital Expenditures	-$2.138B	-$2.208B	$8.001B
YoY Change	-3.17%	1.24%	7.79%
Acquisitions			$65.00M
YoY Change			-93.83%
Other Investing Activities	-$181.0M	-$52.00M	$6.000M
YoY Change	248.08%	-103.1%	-88.68%
Cash From Investing Activities	-$2.319B	-$2.260B	-$5.760B
YoY Change	2.61%	348.41%	-19.89%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net			$1.090B
YoY Change			-237.45%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	462.0M	527.0M	-$1.813B
YoY Change	-12.33%	-251.0%	-290.64%
NET CHANGE
Cash From Operating Activities	900.0M	1.361B	$6.945B
Cash From Investing Activities	-2.319B	-2.260B	-$5.760B
Cash From Financing Activities	462.0M	527.0M	-$1.813B
Net Change In Cash	-957.0M	-372.0M	-$628.0M
YoY Change	157.26%	-228.72%	-505.16%
FREE CASH FLOW
Cash From Operating Activities	$900.0M	$1.361B	$6.945B
Capital Expenditures	-$2.138B	-$2.208B	$8.001B
Free Cash Flow	$3.038B	$3.569B	-$1.056B
YoY Change	-14.88%	7.4%	2.62%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0000092122
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	so	Maximum Deductible Waiting Period MaximumDeductibleWaitingPeriod	P182D
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:LongTermDebtAndCapitalLeaseObligations
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent Statement Of Financial Position Extensible List FinanceLeaseLiabilityNoncurrentStatementOfFinancialPositionExtensibleList	us-gaap:LongTermDebtAndCapitalLeaseObligations
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	so:PlantInServiceNetOfDepreciation
CY2020Q4	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset Statement Of Financial Position Extensible List FinanceLeaseRightOfUseAssetStatementOfFinancialPositionExtensibleList	so:PlantInServiceNetOfDepreciation
CY2019Q4	us-gaap	Finance Lease Liability Current Statement Of Financial Position Extensible List FinanceLeaseLiabilityCurrentStatementOfFinancialPositionExtensibleList	us-gaap:LongTermDebtAndCapitalLeaseObligationsCurrent
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	Current Fiscal Year End Date CurrentFiscalYearEndDate	--12-31
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	1-3526
CY2020	dei	Entity Registrant Name EntityRegistrantName	The Southern Company
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	58-0690070
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	30 Ivan Allen Jr. Boulevard, N.W.
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Atlanta
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	GA
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	30308
CY2020	dei	City Area Code CityAreaCode	404
CY2020	dei	Local Phone Number LocalPhoneNumber	506-5000
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	54800000000	USD
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	1056609660	shares
CY2020	us-gaap	Revenues Revenues	20375000000	USD
CY2019	us-gaap	Revenues Revenues	21419000000	USD
CY2018	us-gaap	Revenues Revenues	23495000000	USD
CY2020	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	5413000000	USD
CY2019	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	5624000000	USD
CY2018	us-gaap	Utilities Operating Expense Maintenance And Operations UtilitiesOperatingExpenseMaintenanceAndOperations	5926000000	USD
CY2020	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3518000000	USD
CY2019	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3038000000	USD
CY2018	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3131000000	USD
CY2020	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	1234000000	USD
CY2019	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	1230000000	USD
CY2018	us-gaap	Taxes Excluding Income And Excise Taxes TaxesExcludingIncomeAndExciseTaxes	1315000000	USD
CY2020	so	Estimated Loss On Plant Vogtle Units3 And4 EstimatedLossOnPlantVogtleUnits3And4	325000000	USD
CY2019	so	Estimated Loss On Plant Vogtle Units3 And4 EstimatedLossOnPlantVogtleUnits3And4	0	USD
CY2018	so	Estimated Loss On Plant Vogtle Units3 And4 EstimatedLossOnPlantVogtleUnits3And4	1060000000	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	0	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	168000000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	210000000	USD
CY2020	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	65000000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	2569000000	USD
CY2018	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	291000000	USD
CY2020	us-gaap	Costs And Expenses CostsAndExpenses	15490000000	USD
CY2019	us-gaap	Costs And Expenses CostsAndExpenses	13683000000	USD
CY2018	us-gaap	Costs And Expenses CostsAndExpenses	19304000000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	4885000000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	7736000000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	4191000000	USD
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	149000000	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	128000000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	138000000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	153000000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	162000000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	148000000	USD
CY2020	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1821000000	USD
CY2019	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1736000000	USD
CY2018	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1842000000	USD
CY2020	so	Lease Impairment Loss LeaseImpairmentLoss	206000000	USD
CY2019	so	Lease Impairment Loss LeaseImpairmentLoss	0	USD
CY2018	so	Lease Impairment Loss LeaseImpairmentLoss	0	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	336000000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	252000000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	114000000	USD
CY2020	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-1389000000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-1194000000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-1442000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	3496000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	6542000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	2749000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	393000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1798000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	449000000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	3103000000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	4744000000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	2300000000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	15000000	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	15000000	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	16000000	USD
CY2020	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-31000000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-10000000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	58000000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	3119000000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	4739000000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2226000000	USD
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.95
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	4.53
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.18
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.93
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	4.50
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.17
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	1058000000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	1046000000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	1020000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	1065000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	1054000000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	1025000000	shares
CY2020	us-gaap	Profit Loss ProfitLoss	3103000000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	4744000000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	2300000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	3000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-39000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationTax	-16000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	10000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-115000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	-47000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	13000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	-19000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationTax	24000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	40000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-57000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossReclassificationAfterTax	-72000000	USD
CY2020	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-17000000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-31000000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodTax	-2000000	USD
CY2020	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-55000000	USD
CY2019	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-64000000	USD
CY2018	us-gaap	Other Comprehensive Income Defined Benefit Plans Net Unamortized Gain Loss Arising During Period Net Of Tax OtherComprehensiveIncomeDefinedBenefitPlansNetUnamortizedGainLossArisingDuringPeriodNetOfTax	-5000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-3000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-1000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossTax	-5000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-10000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-4000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Pension And Other Postretirement Benefit Plans For Net Gain Loss Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIPensionAndOtherPostretirementBenefitPlansForNetGainLossNetOfTax	-6000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-75000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-118000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	26000000	USD
CY2020	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	15000000	USD
CY2019	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	15000000	USD
CY2018	us-gaap	Preferred Stock Dividends Income Statement Impact PreferredStockDividendsIncomeStatementImpact	16000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-31000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-10000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	58000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	3044000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	4621000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	2252000000	USD
CY2020	us-gaap	Profit Loss ProfitLoss	3103000000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	4744000000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	2300000000	USD
CY2020	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	3905000000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	3331000000	USD
CY2018	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	3549000000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-241000000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	611000000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	89000000	USD
CY2020	us-gaap	Investment Tax Credit InvestmentTaxCredit	341000000	USD
CY2019	us-gaap	Investment Tax Credit InvestmentTaxCredit	757000000	USD
CY2018	us-gaap	Investment Tax Credit InvestmentTaxCredit	5000000	USD
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	149000000	USD
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	128000000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Cost Of Equity PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity	138000000	USD
CY2020	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-259000000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-204000000	USD
CY2018	us-gaap	Pension And Other Postretirement Benefit Expense PensionAndOtherPostretirementBenefitExpense	-103000000	USD
CY2020	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	2000000	USD
CY2019	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	1136000000	USD
CY2018	us-gaap	Pension And Other Postretirement Benefit Contributions PensionAndOtherPostretirementBenefitContributions	4000000	USD
CY2020	us-gaap	Asset Retirement Obligation Cash Paid To Settle AssetRetirementObligationCashPaidToSettle	442000000	USD
CY2019	us-gaap	Asset Retirement Obligation Cash Paid To Settle AssetRetirementObligationCashPaidToSettle	328000000	USD
CY2018	us-gaap	Asset Retirement Obligation Cash Paid To Settle AssetRetirementObligationCashPaidToSettle	244000000	USD
CY2020	us-gaap	Storm Damage Provision StormDamageProvision	325000000	USD
CY2019	us-gaap	Storm Damage Provision StormDamageProvision	168000000	USD
CY2018	us-gaap	Storm Damage Provision StormDamageProvision	74000000	USD
CY2020	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	113000000	USD
CY2019	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	107000000	USD
CY2018	us-gaap	Stock Option Plan Expense StockOptionPlanExpense	125000000	USD
CY2020	so	Estimated Loss On Plant Vogtle Units3 And4 Non Cash Adjusted EstimatedLossOnPlantVogtleUnits3And4NonCashAdjusted	325000000	USD
CY2019	so	Estimated Loss On Plant Vogtle Units3 And4 Non Cash Adjusted EstimatedLossOnPlantVogtleUnits3And4NonCashAdjusted	0	USD
CY2018	so	Estimated Loss On Plant Vogtle Units3 And4 Non Cash Adjusted EstimatedLossOnPlantVogtleUnits3And4NonCashAdjusted	1060000000	USD
CY2020	so	Lease And Asset Impairment Charges LeaseAndAssetImpairmentCharges	206000000	USD
CY2019	so	Lease And Asset Impairment Charges LeaseAndAssetImpairmentCharges	168000000	USD
CY2018	so	Lease And Asset Impairment Charges LeaseAndAssetImpairmentCharges	210000000	USD
CY2020	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	66000000	USD
CY2019	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	2588000000	USD
CY2018	us-gaap	Disposal Group Not Discontinued Operation Gain Loss On Disposal DisposalGroupNotDiscontinuedOperationGainLossOnDisposal	301000000	USD
CY2020	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	74000000	USD
CY2019	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-115000000	USD
CY2018	us-gaap	Other Noncash Income Expense OtherNoncashIncomeExpense	-47000000	USD
CY2020	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	222000000	USD
CY2019	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	-630000000	USD
CY2018	us-gaap	Increase Decrease In Receivables IncreaseDecreaseInReceivables	426000000	USD
CY2020	us-gaap	Increase Decrease In Fossil Fuel Inventories IncreaseDecreaseInFossilFuelInventories	29000000	USD
CY2019	us-gaap	Increase Decrease In Fossil Fuel Inventories IncreaseDecreaseInFossilFuelInventories	120000000	USD
CY2018	us-gaap	Increase Decrease In Fossil Fuel Inventories IncreaseDecreaseInFossilFuelInventories	-123000000	USD
CY2020	us-gaap	Increase Decrease In Materials And Supplies IncreaseDecreaseInMaterialsAndSupplies	157000000	USD
CY2019	us-gaap	Increase Decrease In Materials And Supplies IncreaseDecreaseInMaterialsAndSupplies	17000000	USD
CY2018	us-gaap	Increase Decrease In Materials And Supplies IncreaseDecreaseInMaterialsAndSupplies	176000000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	132000000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-132000000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Assets IncreaseDecreaseInOtherOperatingAssets	-98000000	USD
CY2020	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-27000000	USD
CY2019	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	-693000000	USD
CY2018	us-gaap	Increase Decrease In Accounts Payable IncreaseDecreaseInAccountsPayable	291000000	USD
CY2020	so	Increase Decrease In Accrued Taxes IncreaseDecreaseInAccruedTaxes	242000000	USD
CY2019	so	Increase Decrease In Accrued Taxes IncreaseDecreaseInAccruedTaxes	117000000	USD
CY2018	so	Increase Decrease In Accrued Taxes IncreaseDecreaseInAccruedTaxes	267000000	USD
CY2020	so	Increase Decrease Retail Fuel Cost Over Recovery Short Term IncreaseDecreaseRetailFuelCostOverRecoveryShortTerm	-96000000	USD
CY2019	so	Increase Decrease Retail Fuel Cost Over Recovery Short Term IncreaseDecreaseRetailFuelCostOverRecoveryShortTerm	-62000000	USD
CY2018	so	Increase Decrease Retail Fuel Cost Over Recovery Short Term IncreaseDecreaseRetailFuelCostOverRecoveryShortTerm	-36000000	USD
CY2020	so	Increase Decrease In Customer Refunds IncreaseDecreaseInCustomerRefunds	-236000000	USD
CY2019	so	Increase Decrease In Customer Refunds IncreaseDecreaseInCustomerRefunds	126000000	USD
CY2018	so	Increase Decrease In Customer Refunds IncreaseDecreaseInCustomerRefunds	67000000	USD
CY2020	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	76000000	USD
CY2019	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-73000000	USD
CY2018	us-gaap	Increase Decrease In Other Operating Liabilities IncreaseDecreaseInOtherOperatingLiabilities	-4000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	6696000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	5781000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	6945000000	USD
CY2020	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	81000000	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	50000000	USD
CY2018	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	65000000	USD
CY2020	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7441000000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	7555000000	USD
CY2018	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	8001000000	USD
CY2020	us-gaap	Payments To Invest In Decommissioning Fund PaymentsToInvestInDecommissioningFund	877000000	USD
CY2019	us-gaap	Payments To Invest In Decommissioning Fund PaymentsToInvestInDecommissioningFund	888000000	USD
CY2018	us-gaap	Payments To Invest In Decommissioning Fund PaymentsToInvestInDecommissioningFund	1117000000	USD
CY2020	us-gaap	Proceeds From Decommissioning Fund ProceedsFromDecommissioningFund	871000000	USD
CY2019	us-gaap	Proceeds From Decommissioning Fund ProceedsFromDecommissioningFund	882000000	USD
CY2018	us-gaap	Proceeds From Decommissioning Fund ProceedsFromDecommissioningFund	1111000000	USD
CY2020	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	1049000000	USD
CY2019	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	5122000000	USD
CY2018	us-gaap	Proceeds From Divestiture Of Businesses Net Of Cash Divested ProceedsFromDivestitureOfBusinessesNetOfCashDivested	2956000000	USD
CY2020	us-gaap	Payments For Removal Costs PaymentsForRemovalCosts	361000000	USD
CY2019	us-gaap	Payments For Removal Costs PaymentsForRemovalCosts	393000000	USD
CY2018	us-gaap	Payments For Removal Costs PaymentsForRemovalCosts	388000000	USD
CY2020	so	Change In Construction Payables ChangeInConstructionPayables	37000000	USD
CY2019	so	Change In Construction Payables ChangeInConstructionPayables	-169000000	USD
CY2018	so	Change In Construction Payables ChangeInConstructionPayables	50000000	USD
CY2020	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	80000000	USD
CY2019	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	148000000	USD
CY2018	us-gaap	Payments To Acquire Equity Method Investments PaymentsToAcquireEquityMethodInvestments	114000000	USD
CY2020	so	Prepaid Long Term Service Agreement PrepaidLongTermServiceAgreement	211000000	USD
CY2019	so	Prepaid Long Term Service Agreement PrepaidLongTermServiceAgreement	234000000	USD
CY2018	so	Prepaid Long Term Service Agreement PrepaidLongTermServiceAgreement	186000000	USD
CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-64000000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-41000000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	6000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-7030000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-3392000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-5760000000	USD
CY2020	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	1096000000	USD
CY2019	us-gaap	Proceeds From Notes Payable ProceedsFromNotesPayable	640000000	USD
CY2018	us-gaap	Repayments Of Notes Payable RepaymentsOfNotesPayable	774000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Long Term Debt And Capital Securities Net ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet	8047000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt And Capital Securities Net ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet	5220000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Long Term Debt And Capital Securities Net ProceedsFromIssuanceOfLongTermDebtAndCapitalSecuritiesNet	2478000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	74000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	844000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1090000000	USD
CY2020	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	615000000	USD
CY2019	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	350000000	USD
CY2018	us-gaap	Proceeds From Other Short Term Debt ProceedsFromOtherShortTermDebt	3150000000	USD
CY2020	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	4458000000	USD
CY2019	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	4347000000	USD
CY2018	us-gaap	Repayments Of Long Term Debt And Capital Securities RepaymentsOfLongTermDebtAndCapitalSecurities	5533000000	USD
CY2020	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2019	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	0	USD
CY2018	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	33000000	USD
CY2020	us-gaap	Repayments Of Other Short Term Debt RepaymentsOfOtherShortTermDebt	840000000	USD
CY2019	us-gaap	Repayments Of Other Short Term Debt RepaymentsOfOtherShortTermDebt	1850000000	USD
CY2018	us-gaap	Repayments Of Other Short Term Debt RepaymentsOfOtherShortTermDebt	1900000000	USD
CY2020	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	271000000	USD
CY2019	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	256000000	USD
CY2018	us-gaap	Payments To Minority Shareholders PaymentsToMinorityShareholders	153000000	USD
CY2020	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	363000000	USD
CY2019	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	196000000	USD
CY2018	us-gaap	Proceeds From Minority Shareholders ProceedsFromMinorityShareholders	2551000000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	2685000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	2570000000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	2425000000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-325000000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-157000000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-264000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-576000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1930000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1813000000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-910000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	459000000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Excluding Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseExcludingExchangeRateEffect	-628000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1978000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1519000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	2147000000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1068000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1978000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalents	1519000000	USD
CY2020	us-gaap	Interest Paid Capitalized InterestPaidCapitalized	81000000	USD
CY2019	us-gaap	Interest Paid Capitalized InterestPaidCapitalized	74000000	USD
CY2018	us-gaap	Interest Paid Capitalized InterestPaidCapitalized	72000000	USD
CY2020	us-gaap	Interest Paid Net InterestPaidNet	1683000000	USD
CY2019	us-gaap	Interest Paid Net InterestPaidNet	1651000000	USD
CY2018	us-gaap	Interest Paid Net InterestPaidNet	1794000000	USD
CY2020	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	64000000	USD
CY2019	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	276000000	USD
CY2018	us-gaap	Income Taxes Paid Net IncomeTaxesPaidNet	172000000	USD
CY2020	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	989000000	USD
CY2019	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	932000000	USD
CY2018	us-gaap	Capital Expenditures Incurred But Not Yet Paid CapitalExpendituresIncurredButNotYetPaid	1103000000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1065000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	1975000000	USD
CY2019Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	30765000000	USD
CY2020Q4	so	Plant In Service Net Of Depreciation PlantInServiceNetOfDepreciation	78119000000	USD
CY2019Q4	so	Plant In Service Net Of Depreciation PlantInServiceNetOfDepreciation	74349000000	USD
CY2020Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	276000000	USD
CY2020Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	1753000000	USD
CY2019Q4	us-gaap	Accounts Receivable Gross Current AccountsReceivableGrossCurrent	1614000000	USD
CY2020Q4	us-gaap	Energy Marketing Contracts Assets Current EnergyMarketingContractsAssetsCurrent	516000000	USD
CY2019Q4	us-gaap	Energy Marketing Contracts Assets Current EnergyMarketingContractsAssetsCurrent	428000000	USD
CY2020Q4	so	Unbilled Revenues Current UnbilledRevenuesCurrent	672000000	USD
CY2019Q4	so	Unbilled Revenues Current UnbilledRevenuesCurrent	599000000	USD
CY2020Q4	so	Other Accounts Notes And Loans Receivable OtherAccountsNotesAndLoansReceivable	512000000	USD
CY2019Q4	so	Other Accounts Notes And Loans Receivable OtherAccountsNotesAndLoansReceivable	817000000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	118000000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	49000000	USD
CY2020Q4	us-gaap	Other Inventory Supplies OtherInventorySupplies	1478000000	USD
CY2019Q4	us-gaap	Other Inventory Supplies OtherInventorySupplies	1388000000	USD
CY2020Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	550000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Other Fossil Fuel EnergyRelatedInventoryOtherFossilFuel	521000000	USD
CY2020Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	460000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	479000000	USD
CY2019Q4	us-gaap	Prepaid Expense Current PrepaidExpenseCurrent	314000000	USD
CY2020Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	147000000	USD
CY2019Q4	us-gaap	Derivative Assets Current DerivativeAssetsCurrent	183000000	USD
CY2020Q4	so	Regulatory Asset Asset Retirement Obligation Current RegulatoryAssetAssetRetirementObligationCurrent	214000000	USD
CY2019Q4	so	Regulatory Asset Asset Retirement Obligation Current RegulatoryAssetAssetRetirementObligationCurrent	287000000	USD
CY2020Q4	so	Other Regulatory Assets Current OtherRegulatoryAssetsCurrent	810000000	USD
CY2019Q4	so	Other Regulatory Assets Current OtherRegulatoryAssetsCurrent	885000000	USD
CY2020Q4	us-gaap	Assets Held For Sale Not Part Of Disposal Group Current AssetsHeldForSaleNotPartOfDisposalGroupCurrent	60000000	USD
CY2019Q4	us-gaap	Assets Held For Sale Not Part Of Disposal Group Current AssetsHeldForSaleNotPartOfDisposalGroupCurrent	188000000	USD
CY2020Q4	us-gaap	Other Assets Current OtherAssetsCurrent	222000000	USD
CY2019Q4	us-gaap	Other Assets Current OtherAssetsCurrent	188000000	USD
CY2020Q4	us-gaap	Assets Current AssetsCurrent	8617000000	USD
CY2019Q4	us-gaap	Assets Current AssetsCurrent	9817000000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	110516000000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Gross PropertyPlantAndEquipmentGross	105114000000	USD
CY2020Q4	us-gaap	Accumulated Depreciation Depletion And Amortization Property Plant And Equipment AccumulatedDepreciationDepletionAndAmortizationPropertyPlantAndEquipment	32397000000	USD
CY2020Q4	so	Nuclear Fuel At Amortized Cost NuclearFuelAtAmortizedCost	818000000	USD
CY2019Q4	so	Nuclear Fuel At Amortized Cost NuclearFuelAtAmortizedCost	851000000	USD
CY2020Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	8697000000	USD
CY2019Q4	us-gaap	Construction In Progress Gross ConstructionInProgressGross	7880000000	USD
CY2020Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	87634000000	USD
CY2019Q4	us-gaap	Property Plant And Equipment Net PropertyPlantAndEquipmentNet	83080000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2020Q4	us-gaap	Decommissioning Fund Investments DecommissioningFundInvestments	2303000000	USD
CY2019Q4	us-gaap	Decommissioning Fund Investments DecommissioningFundInvestments	2036000000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	1362000000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	1303000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	328000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	280000000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	487000000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	536000000	USD
CY2020Q4	us-gaap	Leveraged Leases Balance Sheet Investment In Leveraged Leases Net LeveragedLeasesBalanceSheetInvestmentInLeveragedLeasesNet	556000000	USD
CY2019Q4	us-gaap	Leveraged Leases Balance Sheet Investment In Leveraged Leases Net LeveragedLeasesBalanceSheetInvestmentInLeveragedLeasesNet	788000000	USD
CY2020Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	398000000	USD
CY2019Q4	us-gaap	Other Long Term Investments OtherLongTermInvestments	391000000	USD
CY2020Q4	us-gaap	Long Term Investments LongTermInvestments	10386000000	USD
CY2019Q4	us-gaap	Long Term Investments LongTermInvestments	10334000000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1802000000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1800000000	USD
CY2020Q4	so	Deferred Charges Related To Income Taxes DeferredChargesRelatedToIncomeTaxes	796000000	USD
CY2019Q4	so	Deferred Charges Related To Income Taxes DeferredChargesRelatedToIncomeTaxes	798000000	USD
CY2020Q4	us-gaap	Unamortized Loss Reacquired Debt Noncurrent UnamortizedLossReacquiredDebtNoncurrent	280000000	USD
CY2019Q4	us-gaap	Unamortized Loss Reacquired Debt Noncurrent UnamortizedLossReacquiredDebtNoncurrent	300000000	USD
CY2020Q4	so	Regulatory Asset Asset Retirement Obligation RegulatoryAssetAssetRetirementObligation	4934000000	USD
CY2019Q4	so	Regulatory Asset Asset Retirement Obligation RegulatoryAssetAssetRetirementObligation	4094000000	USD
CY2020Q4	so	Other Regulatory Assets Deferred OtherRegulatoryAssetsDeferred	7198000000	USD
CY2019Q4	so	Other Regulatory Assets Deferred OtherRegulatoryAssetsDeferred	6805000000	USD
CY2020Q4	us-gaap	Disposal Group Including Discontinued Operation Assets Noncurrent DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent	0	USD
CY2019Q4	us-gaap	Disposal Group Including Discontinued Operation Assets Noncurrent DisposalGroupIncludingDiscontinuedOperationAssetsNoncurrent	601000000	USD
CY2020Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1288000000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	1071000000	USD
CY2020Q4	so	Deferred Charges And Other Assets DeferredChargesAndOtherAssets	16298000000	USD
CY2019Q4	so	Deferred Charges And Other Assets DeferredChargesAndOtherAssets	15469000000	USD
CY2020Q4	us-gaap	Assets Assets	122935000000	USD
CY2019Q4	us-gaap	Assets Assets	118700000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	3507000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	2989000000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	609000000	USD
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	2055000000	USD
CY2020Q4	us-gaap	Energy Marketing Contract Liabilities Current EnergyMarketingContractLiabilitiesCurrent	494000000	USD
CY2019Q4	us-gaap	Energy Marketing Contract Liabilities Current EnergyMarketingContractLiabilitiesCurrent	442000000	USD
CY2020Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	2312000000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	2115000000	USD
CY2020Q4	so	Customer Deposits Current1 CustomerDepositsCurrent1	487000000	USD
CY2019Q4	so	Customer Deposits Current1 CustomerDepositsCurrent1	496000000	USD
CY2020Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	130000000	USD
CY2019Q4	us-gaap	Accrued Income Taxes Current AccruedIncomeTaxesCurrent	0	USD
CY2020Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	699000000	USD
CY2019Q4	us-gaap	Accrual For Taxes Other Than Income Taxes Current AccrualForTaxesOtherThanIncomeTaxesCurrent	659000000	USD
CY2020Q4	us-gaap	Interest Payable Current InterestPayableCurrent	513000000	USD
CY2019Q4	us-gaap	Interest Payable Current InterestPayableCurrent	474000000	USD
CY2020Q4	us-gaap	Accrued Salaries Current AccruedSalariesCurrent	1025000000	USD
CY2019Q4	us-gaap	Accrued Salaries Current AccruedSalariesCurrent	992000000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	585000000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation Current AssetRetirementObligationCurrent	504000000	USD
CY2020Q4	so	Other Regulatory Liabilities Current OtherRegulatoryLiabilitiesCurrent	509000000	USD
CY2019Q4	so	Other Regulatory Liabilities Current OtherRegulatoryLiabilitiesCurrent	756000000	USD
CY2020Q4	so	Liabilities Held For Sale Current LiabilitiesHeldForSaleCurrent	0	USD
CY2019Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	1814000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1611000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1615000000	USD
CY2019Q4	so	Liabilities Held For Sale Current LiabilitiesHeldForSaleCurrent	5000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	241000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	229000000	USD
CY2020Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	968000000	USD
CY2019Q4	us-gaap	Other Liabilities Current OtherLiabilitiesCurrent	830000000	USD
CY2020Q4	us-gaap	Liabilities Current LiabilitiesCurrent	12079000000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	12546000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	45073000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	41798000000	USD
CY2020Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	8175000000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	7888000000	USD
CY2020Q4	so	Deferred Credits Related To Income Taxes DeferredCreditsRelatedToIncomeTaxes	5767000000	USD
CY2019Q4	so	Deferred Credits Related To Income Taxes DeferredCreditsRelatedToIncomeTaxes	6078000000	USD
CY2020Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	2235000000	USD
CY2019Q4	us-gaap	Accumulated Deferred Investment Tax Credit AccumulatedDeferredInvestmentTaxCredit	2291000000	USD
CY2020Q4	us-gaap	Pension And Other Postretirement Defined Benefit Plans Liabilities Noncurrent PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent	2213000000	USD
CY2020Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	10099000000	USD
CY2019Q4	us-gaap	Asset Retirement Obligations Noncurrent AssetRetirementObligationsNoncurrent	9282000000	USD
CY2020Q4	us-gaap	Accrued Environmental Loss Contingencies Noncurrent AccruedEnvironmentalLossContingenciesNoncurrent	216000000	USD
CY2019Q4	us-gaap	Accrued Environmental Loss Contingencies Noncurrent AccruedEnvironmentalLossContingenciesNoncurrent	234000000	USD
CY2020Q4	so	Other Cost Of Removal Obligations OtherCostOfRemovalObligations	2211000000	USD
CY2019Q4	so	Other Cost Of Removal Obligations OtherCostOfRemovalObligations	2239000000	USD
CY2020Q4	so	Other Regulatory Liabilities Deferred OtherRegulatoryLiabilitiesDeferred	251000000	USD
CY2019Q4	so	Other Regulatory Liabilities Deferred OtherRegulatoryLiabilitiesDeferred	256000000	USD
CY2020Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	480000000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	609000000	USD
CY2020Q4	us-gaap	Deferred Credits And Other Liabilities DeferredCreditsAndOtherLiabilities	33258000000	USD
CY2019Q4	us-gaap	Deferred Credits And Other Liabilities DeferredCreditsAndOtherLiabilities	32306000000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	90410000000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	86650000000	USD
CY2020Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	291000000	USD
CY2019Q4	us-gaap	Temporary Equity Carrying Amount Attributable To Parent TemporaryEquityCarryingAmountAttributableToParent	291000000	USD
CY2020Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	5
CY2019Q4	us-gaap	Common Stock Par Or Stated Value Per Share CommonStockParOrStatedValuePerShare	5
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	1500000000	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	1500000000	shares
CY2020Q4	us-gaap	Common Stock Value CommonStockValue	5268000000	USD
CY2019Q4	us-gaap	Common Stock Value CommonStockValue	5257000000	USD
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	1100000000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	1100000000	shares
CY2019Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	1000000.0	shares
CY2020Q4	us-gaap	Treasury Stock Shares TreasuryStockShares	1000000.0	shares
CY2020Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	11834000000	USD
CY2019Q4	us-gaap	Additional Paid In Capital Common Stock AdditionalPaidInCapitalCommonStock	11734000000	USD
CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	46000000	USD
CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	42000000	USD
CY2020Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	11311000000	USD
CY2019Q4	us-gaap	Retained Earnings Accumulated Deficit RetainedEarningsAccumulatedDeficit	10877000000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-395000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Net Of Tax AccumulatedOtherComprehensiveIncomeLossNetOfTax	-321000000	USD
CY2020Q4	us-gaap	Stockholders Equity StockholdersEquity	27972000000	USD
CY2019Q4	us-gaap	Stockholders Equity StockholdersEquity	27505000000	USD
CY2020Q4	us-gaap	Minority Interest MinorityInterest	4262000000	USD
CY2019Q4	us-gaap	Minority Interest MinorityInterest	4254000000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	32234000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	31759000000	USD
CY2020Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	122935000000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	118700000000	USD
CY2020Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	25528000000	USD
CY2018	so	Net Income Loss Including Portion Attributable To Noncontrolling Interest Net Of Preferred Stock Dividends NetIncomeLossIncludingPortionAttributableToNoncontrollingInterestNetOfPreferredStockDividends	2284000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	26000000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	1090000000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	84000000	USD
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.3800
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	2425000000	USD
CY2018	so	Noncontrolling Interest Increasefrom Contributionsfrom Noncontrolling Interest Holders NoncontrollingInterestIncreasefromContributionsfromNoncontrollingInterestHolders	1372000000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	164000000	USD
CY2018	us-gaap	Noncontrolling Interest Increase From Sale Of Parent Equity Interest NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest	1273000000	USD
CY2018	us-gaap	Stockholders Equity Other StockholdersEquityOther	29000000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	29039000000	USD
CY2019	so	Net Income Loss Including Portion Attributable To Noncontrolling Interest Net Of Preferred Stock Dividends NetIncomeLossIncludingPortionAttributableToNoncontrollingInterestNetOfPreferredStockDividends	4729000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-118000000	USD
CY2019	so	Adjustments To Additional Paid In Capital Contract Adjustment Payments AdjustmentsToAdditionalPaidInCapitalContractAdjustmentPayments	198000000	USD
CY2019	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	844000000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	66000000	USD
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.4600
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	2570000000	USD
CY2019	so	Noncontrolling Interest Increasefrom Contributionsfrom Noncontrolling Interest Holders NoncontrollingInterestIncreasefromContributionsfromNoncontrollingInterestHolders	276000000	USD
CY2019	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	327000000	USD
CY2019	us-gaap	Stockholders Equity Other StockholdersEquityOther	-18000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	31759000000	USD
CY2020	so	Net Income Loss Including Portion Attributable To Noncontrolling Interest Net Of Preferred Stock Dividends NetIncomeLossIncludingPortionAttributableToNoncontrollingInterestNetOfPreferredStockDividends	3088000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax Portion Attributable To Parent OtherComprehensiveIncomeLossNetOfTaxPortionAttributableToParent	-75000000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	74000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	44000000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	2.5400
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	2685000000	USD
CY2020	so	Noncontrolling Interest Increasefrom Contributionsfrom Noncontrolling Interest Holders NoncontrollingInterestIncreasefromContributionsfromNoncontrollingInterestHolders	307000000	USD
CY2020	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	271000000	USD
CY2020	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	60000000	USD
CY2020	us-gaap	Noncontrolling Interest Increase From Sale Of Parent Equity Interest NoncontrollingInterestIncreaseFromSaleOfParentEquityInterest	65000000	USD
CY2020	us-gaap	Stockholders Equity Other StockholdersEquityOther	12000000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	32234000000	USD
CY2020	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	230000000	USD
CY2020Q4	so	Number Of Traditional Electric Operating Companies NumberOfTraditionalElectricOperatingCompanies	3	electric_company
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Concentration of Credit Risk</span></div><div style="margin-top:5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Southern Company Gas' wholesale gas services business has a concentration of credit risk for services it provides to its counterparties. This credit risk is generally concentrated in 20 of its counterparties and is measured by 30-day receivable exposure plus forward exposure. Counterparty credit risk is evaluated using a S&P equivalent credit rating, which is determined by a process of converting the lower of the S&P or Moody's rating to an internal rating ranging from 9 to 1, with 9 being equivalent to AAA/Aaa by S&P and Moody's, respectively, and 1 being equivalent to D/Default by S&P and Moody's, respectively. A counterparty that does not have an external rating is assigned an internal rating based on the strength of its financial ratios. As of December 31, 2020, the top 20 counterparties represented </span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">58%,</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> or </span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">$234 million</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, of the total counterparty exposure and had a weighted average S&P equivalent rating of A-.</span></div><div style="margin-top:5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Concentration of credit risk occurs at Atlanta Gas Light for amounts billed for services and other costs to its customers, which consist of</span><span style="background-color:#ffffff;color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> 16</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> Marketers in Georgia (including SouthStar). The credit risk exposure to the Marketers varies seasonally, with the lowest exposure in the non-peak summer months and the highest exposure in the peak winter months. Marketers are responsible for the retail sale of natural gas to end-use customers in Georgia. The functions of the retail sale of gas include the purchase and sale of natural gas, customer service, billings, and collections. The provisions of Atlanta Gas Light's tariff allow Atlanta Gas Light to obtain credit security support in an amount equal to a minimum of two times a Marketer's highest month's estimated bill from Atlanta Gas Light.</span></div>
CY2019	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	202000000	USD
CY2018	us-gaap	Public Utilities Allowance For Funds Used During Construction Capitalized Interest PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedInterest	210000000	USD
CY2020Q4	us-gaap	Goodwill Impairment Loss GoodwillImpairmentLoss	0	USD
CY2020Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	740000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	328000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	412000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	741000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	280000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	461000000	USD
CY2020Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	815000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	328000000	USD
CY2020Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	487000000	USD
CY2019Q4	us-gaap	Intangible Assets Gross Excluding Goodwill IntangibleAssetsGrossExcludingGoodwill	816000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	280000000	USD
CY2019Q4	us-gaap	Intangible Assets Net Excluding Goodwill IntangibleAssetsNetExcludingGoodwill	536000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	49000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	61000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	89000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	43000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	39000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	37000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	35000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	32000000	USD
CY2020	us-gaap	Property Plant And Equipment Preproduction Design And Development Costs PropertyPlantAndEquipmentPreproductionDesignAndDevelopmentCosts	<div style="margin-top:9pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%">Development Costs</span></div><div style="margin-top:5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">For Southern Power, development costs are capitalized once a project is probable of completion, primarily based on a review of its economics and operational feasibility, as well as the status of power off-take agreements and regulatory approvals, if applicable. Southern Power's capitalized development costs are included in CWIP on the balance sheets. All of Southern Power's development costs incurred prior to the determination that a project is probable of completion are expensed as incurred and included in other operations and maintenance expense in the statements of income. If it is determined that a project is no longer probable of completion, any of Southern Power's capitalized development costs are expensed and included in other operations and maintenance expense in the statements of income.</span></div>
CY2019Q4	so	Number Of Leveraged Leases NumberOfLeveragedLeases	4	leveraged_lease
CY2020Q4	so	Number Of Leveraged Leases NumberOfLeveragedLeases	4	leveraged_lease
CY2020Q4	so	Required Collateral Credit Rating Downgrade RequiredCollateralCreditRatingDowngrade	5000000	USD
CY2019Q4	so	Required Collateral Credit Rating Downgrade RequiredCollateralCreditRatingDowngrade	11000000	USD
CY2020	so	Uncollectible Accounts UncollectibleAccounts	0.01
CY2020Q4	us-gaap	Net Regulatory Assets NetRegulatoryAssets	5493000000	USD
CY2019Q4	us-gaap	Net Regulatory Assets NetRegulatoryAssets	3838000000	USD
CY2018	us-gaap	Loss Contingency Number Of Plaintiffs LossContingencyNumberOfPlaintiffs	10	plaintiff
CY2020	so	Maximum Fund Provided For Public Liability Claims MaximumFundProvidedForPublicLiabilityClaims	13800000000	USD
CY2020	so	Maximum Insurance Coverage MaximumInsuranceCoverage	450000000	USD
CY2020	so	Maximum Amount For Each Licensed Reactor MaximumAmountForEachLicensedReactor	138000000	USD
CY2020	so	Maximum Aggregate Amount For Each Incident MaximumAggregateAmountForEachIncident	20000000	USD
CY2020	so	Block Period Considered For Inflation Adjustment Against Maximum Assessment Per Reactor BlockPeriodConsideredForInflationAdjustmentAgainstMaximumAssessmentPerReactor	P5Y
CY2020	so	Maximum Coverage Per Occurrence Per Unit Limit To Obtain Replacement Power MaximumCoveragePerOccurrencePerUnitLimitToObtainReplacementPower	490000000	USD
CY2020	so	Aggregate Payment For Claims Resulting From Terrorist Acts In One Year Period AggregatePaymentForClaimsResultingFromTerroristActsInOneYearPeriod	3200000000	USD
CY2019Q4	so	Number Of Leveraged Leases NumberOfLeveragedLeases	4	leveraged_lease
CY2020Q4	so	Number Of Leveraged Leases NumberOfLeveragedLeases	4	leveraged_lease
CY2020Q4	so	Number Of Domestic Leveraged Leases NumberOfDomesticLeveragedLeases	2	leveraged_lease
CY2019Q4	so	Number Of Domestic Leveraged Leases NumberOfDomesticLeveragedLeases	2	leveraged_lease
CY2020Q4	so	Number Of International Leveraged Leases NumberOfInternationalLeveragedLeases	2	leveraged_lease
CY2019Q4	so	Number Of International Leveraged Leases NumberOfInternationalLeveragedLeases	2	leveraged_lease
CY2019Q4	so	Lease Impairment Loss LeaseImpairmentLoss	17000000	USD
CY2019Q4	so	Lease Impairment Loss After Tax LeaseImpairmentLossAfterTax	13000000	USD
CY2020Q2	so	Lease Impairment Loss LeaseImpairmentLoss	154000000	USD
CY2020Q2	so	Lease Impairment Loss After Tax LeaseImpairmentLossAfterTax	74000000	USD
CY2020Q4	so	Lease Impairment Loss LeaseImpairmentLoss	52000000	USD
CY2020Q4	so	Lease Impairment Loss After Tax LeaseImpairmentLossAfterTax	31000000	USD
CY2020Q4	so	Number Of International Leveraged Leases NumberOfInternationalLeveragedLeases	2	leveraged_lease
CY2020Q4	so	Leveraged Leases Number Of Gas Distribution Networks LeveragedLeasesNumberOfGasDistributionNetworks	9	network
CY2020Q4	so	Leveraged Leases Number Of District Heating Systems LeveragedLeasesNumberOfDistrictHeatingSystems	2	heating_system
CY2019Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	117000000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	61000000	USD
CY2020Q4	so	Leveraged Leases Number Of Assets Remaining LeveragedLeasesNumberOfAssetsRemaining	10	asset
CY2020	so	Leveraged Leases Purchase Option Notice Period LeveragedLeasesPurchaseOptionNoticePeriod	P1Y
CY2020	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	21097000000	USD
CY2020	us-gaap	Revenues Revenues	20375000000	USD
CY2019	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	22596000000	USD
CY2019	us-gaap	Revenues Revenues	21419000000	USD
CY2018	us-gaap	Revenue From Contract With Customer Including Assessed Tax RevenueFromContractWithCustomerIncludingAssessedTax	25241000000	USD
CY2018	us-gaap	Revenues Revenues	23495000000	USD
CY2020Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	2614000000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	2413000000	USD
CY2020Q4	us-gaap	Contract With Customer Asset Net ContractWithCustomerAssetNet	158000000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	52000000	USD
CY2020	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	33000000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	30000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	547000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	395000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	338000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	326000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	306000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	2634000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	52179000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	12879000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	20958000000	USD
CY2020Q4	so	Public Utilities Property Plantand Equipment General PublicUtilitiesPropertyPlantandEquipmentGeneral	5072000000	USD
CY2020Q4	so	Electric Utility Plantin Service ElectricUtilityPlantinService	91088000000	USD
CY2020Q4	so	Public Utilities Property Plantand Equipment Transportationand Distribution PublicUtilitiesPropertyPlantandEquipmentTransportationandDistribution	14610000000	USD
CY2020Q4	so	Public Utilities Property Plantand Equipment Storage Facilities PublicUtilitiesPropertyPlantandEquipmentStorageFacilities	1752000000	USD
CY2020Q4	so	Public Utilities Property Plant And Equipment Other PublicUtilitiesPropertyPlantAndEquipmentOther	1249000000	USD
CY2020Q4	so	Utility Plant In Service UtilityPlantInService	17611000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	1817000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	110516000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Generation Or Processing PublicUtilitiesPropertyPlantAndEquipmentGenerationOrProcessing	50329000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Transmission PublicUtilitiesPropertyPlantAndEquipmentTransmission	12157000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Distribution PublicUtilitiesPropertyPlantAndEquipmentDistribution	19846000000	USD
CY2019Q4	so	Public Utilities Property Plantand Equipment General PublicUtilitiesPropertyPlantandEquipmentGeneral	4650000000	USD
CY2019Q4	so	Electric Utility Plantin Service ElectricUtilityPlantinService	86982000000	USD
CY2019Q4	so	Public Utilities Property Plantand Equipment Transportationand Distribution PublicUtilitiesPropertyPlantandEquipmentTransportationandDistribution	13518000000	USD
CY2019Q4	so	Public Utilities Property Plantand Equipment Storage Facilities PublicUtilitiesPropertyPlantandEquipmentStorageFacilities	1634000000	USD
CY2019Q4	so	Public Utilities Property Plant And Equipment Other PublicUtilitiesPropertyPlantAndEquipmentOther	1192000000	USD
CY2019Q4	so	Utility Plant In Service UtilityPlantInService	16344000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Other Property Plant And Equipment PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment	1788000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	105114000000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	9394000000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	37000000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	328000000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	402000000	USD
CY2019	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	281000000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	9786000000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Incurred AssetRetirementObligationLiabilitiesIncurred	19000000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	442000000	USD
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	409000000	USD
CY2020	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	912000000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	10684000000	USD
CY2020Q4	so	Decommissioning Fund Investments Net Of Receivables DecommissioningFundInvestmentsNetOfReceivables	2301000000	USD
CY2019Q4	so	Decommissioning Fund Investments Net Of Receivables DecommissioningFundInvestmentsNetOfReceivables	2034000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	231000000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	226000000	USD
CY2020Q4	so	Unamortized Fair Value Adjustmentof Longterm Debt UnamortizedFairValueAdjustmentofLongtermDebt	393000000	USD
CY2019Q4	so	Unamortized Fair Value Adjustmentof Longterm Debt UnamortizedFairValueAdjustmentofLongtermDebt	430000000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	201000000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	152000000	USD
CY2020Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	237000000	USD
CY2019Q4	us-gaap	Unamortized Debt Issuance Expense UnamortizedDebtIssuanceExpense	247000000	USD
CY2020Q4	so	Long Term Debtand Finance Lease Obligation Net LongTermDebtandFinanceLeaseObligationNet	48580000000	USD
CY2019Q4	so	Long Term Debtand Finance Lease Obligation Net LongTermDebtandFinanceLeaseObligationNet	44787000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	3507000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	2989000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	45073000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	41798000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	3506000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	3707000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	3131000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	509000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	1191000000	USD
CY2019Q3	so	Number Of Equity Units Issued NumberOfEquityUnitsIssued	34500000	shares
CY2019Q3	so	Equity Units Per Unit Issuance Price EquityUnitsPerUnitIssuancePrice	50
CY2019Q3	us-gaap	Proceeds From Debt Net Of Issuance Costs ProceedsFromDebtNetOfIssuanceCosts	1682000000	USD
CY2019Q3	so	Equity Units Per Unit Issuance Price EquityUnitsPerUnitIssuancePrice	50
CY2019Q3	so	Equity Units Per Unit Issuance Price EquityUnitsPerUnitIssuancePrice	50
CY2019Q3	so	Equity Units Settlement Terms Maximum Number Of Shares EquityUnitsSettlementTermsMaximumNumberOfShares	30200000	shares
CY2020Q4	so	Line Of Credit Expire Year One LineOfCreditExpireYearOne	33000000	USD
CY2020Q4	so	Line Of Credit Expire Year Two LineOfCreditExpireYearTwo	675000000	USD
CY2020Q4	so	Line Of Credit Expire Year Three LineOfCreditExpireYearThree	125000000	USD
CY2020Q4	so	Line Of Credit Expire Year Four LineOfCreditExpireYearFour	6900000000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Maximum Borrowing Capacity LineOfCreditFacilityMaximumBorrowingCapacity	7733000000	USD
CY2020Q4	us-gaap	Line Of Credit Facility Remaining Borrowing Capacity LineOfCreditFacilityRemainingBorrowingCapacity	7671000000	USD
CY2020Q4	so	Bank Credit Arrangements No Term Loan Due With In One Year BankCreditArrangementsNoTermLoanDueWithInOneYear	33000000	USD
CY2020Q4	so	Ratio Of Indebtedness To Capitalization Covenant RatioOfIndebtednessToCapitalizationCovenant	0.70
CY2020Q4	so	Amount Of Variable Rate Pollution Control Revenue Bonds Outstanding Requiring Liquidity Support AmountOfVariableRatePollutionControlRevenueBondsOutstandingRequiringLiquiditySupport	1400000000	USD
CY2020Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	609000000	USD
CY2020Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.003
CY2019Q4	us-gaap	Short Term Borrowings ShortTermBorrowings	2055000000	USD
CY2019Q4	us-gaap	Short Term Debt Weighted Average Interest Rate ShortTermDebtWeightedAverageInterestRate	0.021
CY2020	so	Stock Issued During Period Shares Company Investment Plan And Employee And Director Stock Plans StockIssuedDuringPeriodSharesCompanyInvestmentPlanAndEmployeeAndDirectorStockPlans	3300000	shares
CY2020	us-gaap	Proceeds From Issuance Of Shares Under Incentive And Share Based Compensation Plans Including Stock Options ProceedsFromIssuanceOfSharesUnderIncentiveAndShareBasedCompensationPlansIncludingStockOptions	74000000	USD
CY2020	so	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Pursuant To Stock Based Compensation Plan ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesReservedForIssuancePursuantToStockBasedCompensationPlan	88000000	shares
CY2020	so	Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Reserved For Issuance Pursuant To Stock Based Compensation Plan ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesReservedForIssuancePursuantToStockBasedCompensationPlan	88000000	shares
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	1058000000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	1046000000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	1020000000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	7000000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	8000000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	5000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	1065000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	1054000000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	1025000000	shares
CY2020	so	Undistributed Retained Earnings Of Subsidiaries UndistributedRetainedEarningsOfSubsidiaries	5600000000	USD
CY2020Q4	so	Lease Liability LeaseLiability	2083000000	USD
CY2019Q4	so	Lease Liability LeaseLiability	2070000000	USD
CY2020Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1802000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	241000000	USD
CY2020Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1611000000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	1852000000	USD
CY2020Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	218000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	17000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	214000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	231000000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	1800000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	229000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	1615000000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	1844000000	USD
CY2019Q4	us-gaap	Finance Lease Right Of Use Asset FinanceLeaseRightOfUseAsset	216000000	USD
CY2019Q4	us-gaap	Finance Lease Liability Current FinanceLeaseLiabilityCurrent	21000000	USD
CY2019Q4	us-gaap	Finance Lease Liability Noncurrent FinanceLeaseLiabilityNoncurrent	205000000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	226000000	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	309000000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	26000000	USD
CY2020	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	11000000	USD
CY2020	so	Finance Lease Cost FinanceLeaseCost	37000000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	39000000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	91000000	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	0	USD
CY2020	us-gaap	Lease Cost LeaseCost	476000000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	310000000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	28000000	USD
CY2019	us-gaap	Finance Lease Interest Expense FinanceLeaseInterestExpense	12000000	USD
CY2019	so	Finance Lease Cost FinanceLeaseCost	40000000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	48000000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	105000000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	0	USD
CY2019	us-gaap	Lease Cost LeaseCost	503000000	USD
CY2018	so	Leases Rent Expense LeasesRentExpense	192000000	USD
CY2018	so	Leases Ppa Capacity Expense LeasesPPACapacityExpense	231000000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	310000000	USD
CY2020	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	9000000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	22000000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	227000000	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	10000000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	323000000	USD
CY2019	us-gaap	Finance Lease Interest Payment On Liability FinanceLeaseInterestPaymentOnLiability	10000000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	32000000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	118000000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	35000000	USD
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P14Y6M
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P18Y2M12D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0444
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0479
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P14Y2M12D
CY2019Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P18Y9M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0453
CY2019Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0504
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	300000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	287000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	230000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	187000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	165000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	1546000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	2715000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	863000000	USD
CY2020Q4	so	Operating Lease Liability Including Held For Sale OperatingLeaseLiabilityIncludingHeldForSale	1852000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Next Twelve Months FinanceLeaseLiabilityPaymentsDueNextTwelveMonths	28000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Two FinanceLeaseLiabilityPaymentsDueYearTwo	25000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Three FinanceLeaseLiabilityPaymentsDueYearThree	22000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Four FinanceLeaseLiabilityPaymentsDueYearFour	19000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due Year Five FinanceLeaseLiabilityPaymentsDueYearFive	16000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due After Year Five FinanceLeaseLiabilityPaymentsDueAfterYearFive	246000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Payments Due FinanceLeaseLiabilityPaymentsDue	356000000	USD
CY2020Q4	us-gaap	Finance Lease Liability Undiscounted Excess Amount FinanceLeaseLiabilityUndiscountedExcessAmount	125000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	231000000	USD
CY2020	us-gaap	Sales Type Lease Interest Income SalesTypeLeaseInterestIncome	16000000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	208000000	USD
CY2020	us-gaap	Variable Lease Income VariableLeaseIncome	419000000	USD
CY2020	us-gaap	Lease Income LeaseIncome	643000000	USD
CY2019	us-gaap	Sales Type Lease Interest Income SalesTypeLeaseInterestIncome	9000000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	273000000	USD
CY2019	us-gaap	Variable Lease Income VariableLeaseIncome	403000000	USD
CY2019	us-gaap	Lease Income LeaseIncome	685000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Next Twelve Months LessorOperatingLeasePaymentsToBeReceivedNextTwelveMonths	207000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Two Years LessorOperatingLeasePaymentsToBeReceivedTwoYears	187000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Three Years LessorOperatingLeasePaymentsToBeReceivedThreeYears	138000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Four Years LessorOperatingLeasePaymentsToBeReceivedFourYears	106000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Five Years LessorOperatingLeasePaymentsToBeReceivedFiveYears	99000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received Thereafter LessorOperatingLeasePaymentsToBeReceivedThereafter	978000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Payments To Be Received LessorOperatingLeasePaymentsToBeReceived	1715000000	USD
CY2020	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	199000000	USD
CY2020	so	Effective Income Tax Rate Reconciliation Tax Credit Production Percent EffectiveIncomeTaxRateReconciliationTaxCreditProductionPercent	0
CY2020	so	Effective Income Tax Rate Reconciliation Amortization Tax Credits Investment EffectiveIncomeTaxRateReconciliationAmortizationTaxCreditsInvestment	0.016
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	70000000	USD
CY2020	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	269000000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	100000000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	24000000	USD
CY2020	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	124000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	393000000	USD
CY2019	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	156000000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	1237000000	USD
CY2019	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	1393000000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	275000000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	130000000	USD
CY2019	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	405000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1798000000	USD
CY2018	us-gaap	Current Federal Tax Expense Benefit CurrentFederalTaxExpenseBenefit	167000000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	231000000	USD
CY2018	us-gaap	Federal Income Tax Expense Benefit Continuing Operations FederalIncomeTaxExpenseBenefitContinuingOperations	398000000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	188000000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-137000000	USD
CY2018	us-gaap	State And Local Income Tax Expense Benefit Continuing Operations StateAndLocalIncomeTaxExpenseBenefitContinuingOperations	51000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	449000000	USD
CY2020	so	Amortization Of Deferred Investment Tax Credits AmortizationOfDeferredInvestmentTaxCredits	84000000	USD
CY2019	so	Amortization Of Deferred Investment Tax Credits AmortizationOfDeferredInvestmentTaxCredits	181000000	USD
CY2018	so	Amortization Of Deferred Investment Tax Credits AmortizationOfDeferredInvestmentTaxCredits	87000000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2020	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.028
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Deductions Employee Stock Ownership Plan Dividends EffectiveIncomeTaxRateReconciliationDeductionsEmployeeStockOwnershipPlanDividends	0.007
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depreciation EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciation	0.007
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.088
CY2020	so	Afudc Equity AfudcEquity	0.008
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	0
CY2020Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	8043000000	USD
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Leases EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLeases	0.016
CY2020	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0.002
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.112
CY2019	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2019	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.049
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Deductions Employee Stock Ownership Plan Dividends EffectiveIncomeTaxRateReconciliationDeductionsEmployeeStockOwnershipPlanDividends	0.004
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depreciation EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciation	0.003
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.021
CY2019	so	Afudc Equity AfudcEquity	0.004
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	0.001
CY2019	so	Effective Income Tax Rate Reconciliation Amortization Tax Credits Investment EffectiveIncomeTaxRateReconciliationAmortizationTaxCreditsInvestment	0.008
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0.051
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	0
CY2019	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	0
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.275
CY2018	us-gaap	Effective Income Tax Rate Reconciliation At Federal Statutory Income Tax Rate EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate	0.210
CY2018	us-gaap	Effective Income Tax Rate Reconciliation State And Local Income Taxes EffectiveIncomeTaxRateReconciliationStateAndLocalIncomeTaxes	0.018
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Deductions Employee Stock Ownership Plan Dividends EffectiveIncomeTaxRateReconciliationDeductionsEmployeeStockOwnershipPlanDividends	0.010
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Nondeductible Expense Depreciation EffectiveIncomeTaxRateReconciliationNondeductibleExpenseDepreciation	0.008
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Prior Year Income Taxes EffectiveIncomeTaxRateReconciliationPriorYearIncomeTaxes	-0.040
CY2018	so	Afudc Equity AfudcEquity	0.010
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Tax Credits Investment EffectiveIncomeTaxRateReconciliationTaxCreditsInvestment	0.006
CY2018	so	Effective Income Tax Rate Reconciliation Tax Credit Production Percent EffectiveIncomeTaxRateReconciliationTaxCreditProductionPercent	0.047
CY2018	so	Effective Income Tax Rate Reconciliation Amortization Tax Credits Investment EffectiveIncomeTaxRateReconciliationAmortizationTaxCreditsInvestment	0.020
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Disposition Of Business EffectiveIncomeTaxRateReconciliationDispositionOfBusiness	0.086
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Change In Enacted Tax Rate EffectiveIncomeTaxRateReconciliationChangeInEnactedTaxRate	-0.014
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Minority Interest Income Expense EffectiveIncomeTaxRateReconciliationMinorityInterestIncomeExpense	0.004
CY2018	us-gaap	Effective Income Tax Rate Reconciliation Other Adjustments EffectiveIncomeTaxRateReconciliationOtherAdjustments	-0.008
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.163
CY2020Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	16781000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	8874000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	136000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	8738000000	USD
CY2020Q4	so	Accumulated Deferred Tax Assets AccumulatedDeferredTaxAssets	132000000	USD
CY2020Q4	so	Accumulated Deferred Tax Liabilities AccumulatedDeferredTaxLiabilities	8175000000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities DeferredIncomeTaxLiabilities	16261000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	8680000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Valuation Allowance DeferredTaxAssetsValuationAllowance	137000000	USD
CY2019Q4	us-gaap	Deferred Tax Assets Net DeferredTaxAssetsNet	8543000000	USD
CY2019Q4	us-gaap	Deferred Tax Liabilities DeferredTaxLiabilities	7718000000	USD
CY2019Q4	so	Accumulated Deferred Tax Assets AccumulatedDeferredTaxAssets	170000000	USD
CY2019Q4	so	Accumulated Deferred Tax Liabilities AccumulatedDeferredTaxLiabilities	7888000000	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards State And Local DeferredTaxAssetsOperatingLossCarryforwardsStateAndLocal	299000000	USD
CY2017Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	18000000	USD
CY2018	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsDecreasesResultingFromPriorPeriodTaxPositions	18000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	0	USD
CY2020	us-gaap	Unrecognized Tax Benefits Increases Resulting From Prior Period Tax Positions UnrecognizedTaxBenefitsIncreasesResultingFromPriorPeriodTaxPositions	44000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	44000000	USD
CY2020	so	Period Over Which Company Has Elected To Amortize Changes In Market Value Of All Plan Assets PeriodOverWhichCompanyHasElectedToAmortizeChangesInMarketValueOfAllPlanAssets	P5Y
CY2020Q4	us-gaap	Defined Benefit Plan Plan Assets Target Allocation Percentage DefinedBenefitPlanPlanAssetsTargetAllocationPercentage	1
CY2020Q4	us-gaap	Defined Benefit Plan Weighted Average Asset Allocations DefinedBenefitPlanWeightedAverageAssetAllocations	1
CY2019	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	482000000	USD
CY2018	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	41000000	USD
CY2020Q4	so	Number Of Employees Participatingin Stock Optionand Performance Share Units Program NumberOfEmployeesParticipatinginStockOptionandPerformanceShareUnitsProgram	1958	employee
CY2020Q1	us-gaap	Conversion Of Stock Shares Converted1 ConversionOfStockSharesConverted1	1800000	shares
CY2020Q1	so	Common Stock Conversion Price CommonStockConversionPrice	68.59
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	5900000	shares
CY2019Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	42.52
CY2020	us-gaap	Stock Issued During Period Shares Stock Options Exercised StockIssuedDuringPeriodSharesStockOptionsExercised	1600000	shares
CY2020	us-gaap	Share Based Compensation Arrangements By Share Based Payment Award Options Exercises In Period Weighted Average Exercise Price ShareBasedCompensationArrangementsByShareBasedPaymentAwardOptionsExercisesInPeriodWeightedAverageExercisePrice	41.13
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Number ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingNumber	4300000	shares
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Weighted Average Exercise Price ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingWeightedAverageExercisePrice	43.04
CY2020	us-gaap	Proceeds From Stock Options Exercised ProceedsFromStockOptionsExercised	66000000	USD
CY2020Q4	us-gaap	Sharebased Compensation Arrangement By Sharebased Payment Award Options Exercisable Intrinsic Value1 SharebasedCompensationArrangementBySharebasedPaymentAwardOptionsExercisableIntrinsicValue1	78000000	USD
CY2020Q4	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Outstanding Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOutstandingIntrinsicValue	78000000	USD
CY2020	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	38000000	USD
CY2019	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	167000000	USD
CY2018	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Options Exercises In Period Total Intrinsic Value ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodTotalIntrinsicValue	9000000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	9000000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	35000000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Exercise Of Stock Options EmployeeServiceShareBasedCompensationTaxBenefitFromExerciseOfStockOptions	2000000	USD
CY2020Q4	so	Weather Derivative Premium WeatherDerivativePremium	6000000	USD
CY2020Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	28000000	USD
CY2019Q4	so	Weather Derivative Premium WeatherDerivativePremium	4000000	USD
CY2019Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	99000000	USD
CY2020Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	48349000000	USD
CY2020Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	56264000000	USD
CY2019Q4	us-gaap	Debt Instrument Carrying Amount DebtInstrumentCarryingAmount	44561000000	USD
CY2019Q4	us-gaap	Debt Instrument Fair Value DebtInstrumentFairValue	48339000000	USD
CY2020	so	Expected Volume Of Natural Gas Subject To Option To Sell Back Excess Gas Due To Operational Constraints ExpectedVolumeOfNaturalGasSubjectToOptionToSellBackExcessGasDueToOperationalConstraints	29000000	MMBTU
CY2020Q4	us-gaap	Interest Rate Cash Flow Hedge Gain Loss To Be Reclassified During Next12 Months Net InterestRateCashFlowHedgeGainLossToBeReclassifiedDuringNext12MonthsNet	-25000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	810000000	USD
CY2020Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	621000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Asset DerivativeFairValueOfDerivativeAsset	696000000	USD
CY2019Q4	us-gaap	Derivative Fair Value Of Derivative Liability DerivativeFairValueOfDerivativeLiability	751000000	USD
CY2020Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	529000000	USD
CY2020Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	557000000	USD
CY2019Q4	us-gaap	Derivative Asset Fair Value Gross Liability DerivativeAssetFairValueGrossLiability	463000000	USD
CY2019Q4	us-gaap	Derivative Liability Fair Value Gross Asset DerivativeLiabilityFairValueGrossAsset	562000000	USD
CY2020Q4	us-gaap	Derivative Assets DerivativeAssets	281000000	USD
CY2020Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	64000000	USD
CY2019Q4	us-gaap	Derivative Assets DerivativeAssets	233000000	USD
CY2019Q4	us-gaap	Derivative Liabilities DerivativeLiabilities	189000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	14000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	-154000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss After Reclassification Before Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossAfterReclassificationBeforeTax	-62000000	USD
CY2020	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3518000000	USD
CY2019	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3038000000	USD
CY2018	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3131000000	USD
CY2020	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1821000000	USD
CY2019	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1736000000	USD
CY2018	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1842000000	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	336000000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	252000000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	114000000	USD
CY2020	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	149000000	USD
CY2019	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	233000000	USD
CY2018	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	-128000000	USD
CY2020Q4	us-gaap	Collateral Already Posted Aggregate Fair Value CollateralAlreadyPostedAggregateFairValue	28000000	USD
CY2020	us-gaap	Revenues Revenues	20375000000	USD
CY2020	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3518000000	USD
CY2020	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	37000000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	153000000	USD
CY2020	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1821000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	393000000	USD
CY2020	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	3119000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2020Q4	us-gaap	Assets Assets	122935000000	USD
CY2019	us-gaap	Revenues Revenues	21419000000	USD
CY2019	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3038000000	USD
CY2019	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	60000000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	162000000	USD
CY2019	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1736000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	1798000000	USD
CY2019	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	4739000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	5280000000	USD
CY2019Q4	us-gaap	Assets Assets	118700000000	USD
CY2018	us-gaap	Revenues Revenues	23495000000	USD
CY2018	so	Depreciation And Amortization Excluding Nuclear Fuel DepreciationAndAmortizationExcludingNuclearFuel	3131000000	USD
CY2018	us-gaap	Investment Income Interest And Dividend InvestmentIncomeInterestAndDividend	38000000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	148000000	USD
CY2018	us-gaap	Interest And Debt Expense InterestAndDebtExpense	1842000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	449000000	USD
CY2018	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	2226000000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	5315000000	USD
CY2018Q4	us-gaap	Assets Assets	116914000000	USD
CY2019Q4	so	Lease Impairment Loss LeaseImpairmentLoss	17000000	USD
CY2019Q4	so	Lease Impairment Loss After Tax LeaseImpairmentLossAfterTax	13000000	USD

Files In Submission

Name	View Source	Status
0000092122-21-000006-index-headers.html	Edgar Link	pending
0000092122-21-000006-index.html	Edgar Link	pending
0000092122-21-000006.txt	Edgar Link	pending
0000092122-21-000006-xbrl.zip	Edgar Link	pending
apc_logoxhorzreduced1a.jpg	Edgar Link	pending
FilingSummary.xml	Edgar Link	unprocessable
Financial_Report.xlsx	Edgar Link	pending
gpc_logoxhorzlh1.jpg	Edgar Link	pending
MetaLinks.json	Edgar Link	pending
R1.htm	Edgar Link	pending
R10.htm	Edgar Link	pending
R100.htm	Edgar Link	pending
R101.htm	Edgar Link	pending
R102.htm	Edgar Link	pending
R103.htm	Edgar Link	pending
R104.htm	Edgar Link	pending
R105.htm	Edgar Link	pending
R106.htm	Edgar Link	pending
R107.htm	Edgar Link	pending
R108.htm	Edgar Link	pending
R109.htm	Edgar Link	pending
R11.htm	Edgar Link	pending
R110.htm	Edgar Link	pending
R111.htm	Edgar Link	pending
R112.htm	Edgar Link	pending
R113.htm	Edgar Link	pending
R114.htm	Edgar Link	pending
R115.htm	Edgar Link	pending
R116.htm	Edgar Link	pending
R117.htm	Edgar Link	pending
R118.htm	Edgar Link	pending
R119.htm	Edgar Link	pending
R12.htm	Edgar Link	pending
R120.htm	Edgar Link	pending
R121.htm	Edgar Link	pending
R122.htm	Edgar Link	pending
R123.htm	Edgar Link	pending
R124.htm	Edgar Link	pending
R125.htm	Edgar Link	pending
R126.htm	Edgar Link	pending
R127.htm	Edgar Link	pending
R128.htm	Edgar Link	pending
R129.htm	Edgar Link	pending
R13.htm	Edgar Link	pending
R130.htm	Edgar Link	pending
R131.htm	Edgar Link	pending
R132.htm	Edgar Link	pending
R133.htm	Edgar Link	pending
R134.htm	Edgar Link	pending
R135.htm	Edgar Link	pending
R136.htm	Edgar Link	pending
R137.htm	Edgar Link	pending
R138.htm	Edgar Link	pending
R139.htm	Edgar Link	pending
R14.htm	Edgar Link	pending
R140.htm	Edgar Link	pending
R141.htm	Edgar Link	pending
R142.htm	Edgar Link	pending
R143.htm	Edgar Link	pending
R144.htm	Edgar Link	pending
R145.htm	Edgar Link	pending
R146.htm	Edgar Link	pending
R147.htm	Edgar Link	pending
R148.htm	Edgar Link	pending
R149.htm	Edgar Link	pending
R15.htm	Edgar Link	pending
R150.htm	Edgar Link	pending
R151.htm	Edgar Link	pending
R152.htm	Edgar Link	pending
R153.htm	Edgar Link	pending
R154.htm	Edgar Link	pending
R155.htm	Edgar Link	pending
R156.htm	Edgar Link	pending
R157.htm	Edgar Link	pending
R158.htm	Edgar Link	pending
R159.htm	Edgar Link	pending
R16.htm	Edgar Link	pending
R160.htm	Edgar Link	pending
R161.htm	Edgar Link	pending
R162.htm	Edgar Link	pending
R163.htm	Edgar Link	pending
R164.htm	Edgar Link	pending
R165.htm	Edgar Link	pending
R166.htm	Edgar Link	pending
R167.htm	Edgar Link	pending
R168.htm	Edgar Link	pending
R169.htm	Edgar Link	pending
R17.htm	Edgar Link	pending
R170.htm	Edgar Link	pending
R171.htm	Edgar Link	pending
R172.htm	Edgar Link	pending
R173.htm	Edgar Link	pending
R174.htm	Edgar Link	pending
R175.htm	Edgar Link	pending
R176.htm	Edgar Link	pending
R177.htm	Edgar Link	pending
R178.htm	Edgar Link	pending
R179.htm	Edgar Link	pending
R18.htm	Edgar Link	pending
R180.htm	Edgar Link	pending
R181.htm	Edgar Link	pending
R182.htm	Edgar Link	pending
R183.htm	Edgar Link	pending
R184.htm	Edgar Link	pending
R185.htm	Edgar Link	pending
R186.htm	Edgar Link	pending
R187.htm	Edgar Link	pending
R188.htm	Edgar Link	pending
R189.htm	Edgar Link	pending
R19.htm	Edgar Link	pending
R190.htm	Edgar Link	pending
R191.htm	Edgar Link	pending
R192.htm	Edgar Link	pending
R193.htm	Edgar Link	pending
R194.htm	Edgar Link	pending
R195.htm	Edgar Link	pending
R196.htm	Edgar Link	pending
R197.htm	Edgar Link	pending
R198.htm	Edgar Link	pending
R199.htm	Edgar Link	pending
R2.htm	Edgar Link	pending
R20.htm	Edgar Link	pending
R200.htm	Edgar Link	pending
R201.htm	Edgar Link	pending
R202.htm	Edgar Link	pending
R203.htm	Edgar Link	pending
R21.htm	Edgar Link	pending
R22.htm	Edgar Link	pending
R23.htm	Edgar Link	pending
R24.htm	Edgar Link	pending
R25.htm	Edgar Link	pending
R26.htm	Edgar Link	pending
R27.htm	Edgar Link	pending
R28.htm	Edgar Link	pending
R29.htm	Edgar Link	pending
R3.htm	Edgar Link	pending
R30.htm	Edgar Link	pending
R31.htm	Edgar Link	pending
R32.htm	Edgar Link	pending
R33.htm	Edgar Link	pending
R34.htm	Edgar Link	pending
R35.htm	Edgar Link	pending
R36.htm	Edgar Link	pending
R37.htm	Edgar Link	pending
R38.htm	Edgar Link	pending
R39.htm	Edgar Link	pending
R4.htm	Edgar Link	pending
R40.htm	Edgar Link	pending
R41.htm	Edgar Link	pending
R42.htm	Edgar Link	pending
R43.htm	Edgar Link	pending
R44.htm	Edgar Link	pending
R45.htm	Edgar Link	pending
R46.htm	Edgar Link	pending
R47.htm	Edgar Link	pending
R48.htm	Edgar Link	pending
R49.htm	Edgar Link	pending
R5.htm	Edgar Link	pending
R50.htm	Edgar Link	pending
R51.htm	Edgar Link	pending
R52.htm	Edgar Link	pending
R53.htm	Edgar Link	pending
R54.htm	Edgar Link	pending
R55.htm	Edgar Link	pending
R56.htm	Edgar Link	pending
R57.htm	Edgar Link	pending
R58.htm	Edgar Link	pending
R59.htm	Edgar Link	pending
R6.htm	Edgar Link	pending
R60.htm	Edgar Link	pending
R61.htm	Edgar Link	pending
R62.htm	Edgar Link	pending
R63.htm	Edgar Link	pending
R64.htm	Edgar Link	pending
R65.htm	Edgar Link	pending
R66.htm	Edgar Link	pending
R67.htm	Edgar Link	pending
R68.htm	Edgar Link	pending
R69.htm	Edgar Link	pending
R7.htm	Edgar Link	pending
R70.htm	Edgar Link	pending
R71.htm	Edgar Link	pending
R72.htm	Edgar Link	pending
R73.htm	Edgar Link	pending
R74.htm	Edgar Link	pending
R75.htm	Edgar Link	pending
R76.htm	Edgar Link	pending
R77.htm	Edgar Link	pending
R78.htm	Edgar Link	pending
R79.htm	Edgar Link	pending
R8.htm	Edgar Link	pending
R80.htm	Edgar Link	pending
R81.htm	Edgar Link	pending
R82.htm	Edgar Link	pending
R83.htm	Edgar Link	pending
R84.htm	Edgar Link	pending
R85.htm	Edgar Link	pending
R86.htm	Edgar Link	pending
R87.htm	Edgar Link	pending
R88.htm	Edgar Link	pending
R89.htm	Edgar Link	pending
R9.htm	Edgar Link	pending
R90.htm	Edgar Link	pending
R91.htm	Edgar Link	pending
R92.htm	Edgar Link	pending
R93.htm	Edgar Link	pending
R94.htm	Edgar Link	pending
R95.htm	Edgar Link	pending
R96.htm	Edgar Link	pending
R97.htm	Edgar Link	pending
R98.htm	Edgar Link	pending
R99.htm	Edgar Link	pending
report.css	Edgar Link	pending
Show.js	Edgar Link	pending
so-20201231.htm	Edgar Link	pending
so-20201231.xsd	Edgar Link	pending
so-20201231_cal.xml	Edgar Link	unprocessable
so-20201231_def.xml	Edgar Link	unprocessable
so-20201231_htm.xml	Edgar Link	completed
so-20201231_lab.xml	Edgar Link	unprocessable
so-20201231_pre.xml	Edgar Link	unprocessable
socogas_logoxhorzlh1a.jpg	Edgar Link	pending
x10a10-q42020.htm	Edgar Link	pending
x10a24-q420203rdamdefcompp.htm	Edgar Link	pending
x10a25-q420207thamsupbenpl.htm	Edgar Link	pending
x10a26-q420204thamesp.htm	Edgar Link	pending
x10a9-q42020defsttragreedir.htm	Edgar Link	pending
x21a-q42020.htm	Edgar Link	pending
x23a1-q42020soconsent.htm	Edgar Link	pending
x23b1-q42020apcconsent.htm	Edgar Link	pending
x23c1-q42020gpcconsent.htm	Edgar Link	pending
x23d1-q42020mpcconsent.htm	Edgar Link	pending
x23e1-q42020spcconsent.htm	Edgar Link	pending
x23f1-q42020gasconsent.htm	Edgar Link	pending
x23f2-q42020bdoconsent.htm	Edgar Link	pending
x24a-q42020southernpoafor2.htm	Edgar Link	pending
x24b-q42020alpoafor202010xk.htm	Edgar Link	pending
x24c1-q42020gapoafor202010.htm	Edgar Link	pending
x24c2-q42020tuckergpcpoa.htm	Edgar Link	pending
x24d1-q42020mspoafor202010.htm	Edgar Link	pending
x24d2-q42020grahammspowerp.htm	Edgar Link	pending
x24e1-q42020sopowerpoafor2.htm	Edgar Link	pending
x24e2-q42020sopowerpoafor2.htm	Edgar Link	pending
x24f1-q42020gaspoafor20201.htm	Edgar Link	pending
x24f2-q42020porochgaspoa.htm	Edgar Link	pending
x31a1-q42020.htm	Edgar Link	pending
x31a2-q42020.htm	Edgar Link	pending
x31b1-q42020.htm	Edgar Link	pending
x31b2-q42020.htm	Edgar Link	pending
x31c1-q42020.htm	Edgar Link	pending
x31c2-q42020.htm	Edgar Link	pending
x31d1-q42020.htm	Edgar Link	pending
x31d2-q42020.htm	Edgar Link	pending
x31e1-q42020.htm	Edgar Link	pending
x31e2-q42020.htm	Edgar Link	pending
x31f1-q42020.htm	Edgar Link	pending
x31f2-q42020.htm	Edgar Link	pending
x32a-q42020.htm	Edgar Link	pending
x32b-q42020.htm	Edgar Link	pending
x32c-q42020.htm	Edgar Link	pending
x32d-q42020.htm	Edgar Link	pending
x32e-q42020.htm	Edgar Link	pending
x32f-q42020.htm	Edgar Link	pending
x4a4-q42020.htm	Edgar Link	pending
x4f6-q42020nicorsupind.htm	Edgar Link	pending

Create your account

Find Stocks Worth Researching

Deeply Understand Businesses

Value Businesses Intelligently

$SO
SOUTHERN CO Stock $so

2019 Q4 Form 10-K Financial Statement

#000009212221000006 Filed on February 18, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SO SOUTHERN CO Stock $so

2019 Q4 Form 10-K Financial Statement

#000009212221000006 Filed on February 18, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$SO
SOUTHERN CO Stock $so