$NRG
NRG ENERGY, INC. Stock $nrg

$nrg Overview Financials Valuation SEC Filings Company Website

2020 Form 10-K Financial Statement

#000101387121000005 Filed on March 01, 2021

Income Statement

Concept	2020	2019 Q4	2019
Revenue	$9.093B	$2.195B	$9.821B
YoY Change	-7.41%	10.19%	3.62%
Cost Of Revenue	$6.540B	$1.654B	$7.303B
YoY Change	-10.45%	20.03%	2.74%
Gross Profit	$2.553B	$541.0M	$2.518B
YoY Change	1.39%	77.38%	6.24%
Gross Profit Margin	28.08%	24.65%	25.64%
Selling, General & Admin	$810.0M	$212.0M	$760.0M
YoY Change	6.58%	1.92%	-4.88%
% of Gross Profit	31.73%	39.19%	30.18%
Research & Development	$8.000M	$2.000M	$7.000M
YoY Change	14.29%	0.0%	-36.36%
% of Gross Profit	0.31%	0.37%	0.28%
Depreciation & Amortization	$435.0M	$134.0M	$373.0M
YoY Change	16.62%	48.89%	-11.4%
% of Gross Profit	17.04%	24.77%	14.81%
Operating Expenses	$818.0M	$326.0M	$767.0M
YoY Change	6.65%	24.9%	-5.31%
Operating Profit	$1.105B	$209.0M	$1.290B
YoY Change	-14.34%	326.53%	31.36%
Interest Expense	$401.0M	-$101.0M	$413.0M
YoY Change	-2.91%	-27.34%	-14.49%
% of Operating Profit	36.29%	-48.33%	32.02%
Other Income/Expense, Net	-$344.0M	$17.00M	-$504.0M
YoY Change	-31.75%	-22.73%	-2.14%
Pretax Income	$761.0M	$120.0M	$786.0M
YoY Change	-3.18%	-178.43%	68.31%
Income Tax	$251.0M	-$3.343B	-$3.334B
% Of Pretax Income	32.98%	-2785.83%	-424.17%
Net Earnings	$510.0M	$3.385B	$4.438B
YoY Change	-88.51%	-26138.46%	1555.97%
Net Earnings / Revenue	5.61%	154.21%	45.19%
Basic Earnings Per Share	$2.08	$13.48	$16.94
Diluted Earnings Per Share	$2.07	$13.37	$16.81
COMMON SHARES
Basic Shares Outstanding	245.0M shares	251.0M shares	262.0M shares
Diluted Shares Outstanding	246.0M shares	253.0M shares	264.0M shares

Balance Sheet

Concept	2020	2019 Q4	2019
SHORT-TERM ASSETS
Cash & Short-Term Investments	$3.905B	$345.0M	$345.0M
YoY Change	1031.88%	-38.72%	-38.72%
Cash & Equivalents	$3.905B	$345.0M	$345.0M
Short-Term Investments
Other Short-Term Assets	$892.0M	$1.335B	$1.335B
YoY Change	-33.18%	-16.61%	-16.61%
Inventory	$327.0M	$383.0M	$383.0M
Prepaid Expenses
Receivables	$904.0M	$1.025B	$1.025B
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$6.028B	$3.088B	$3.088B
YoY Change	95.21%	-14.22%	-14.22%
LONG-TERM ASSETS
Property, Plant & Equipment	$2.848B	$2.593B	$3.057B
YoY Change	-6.84%	-14.93%	0.3%
Goodwill		$579.0M
YoY Change		1.05%
Intangibles
YoY Change
Long-Term Investments	$346.0M	$388.0M	$388.0M
YoY Change	-10.82%	-5.83%	-5.83%
Other Assets	$4.433B	$240.0M	$4.630B
YoY Change	-4.25%	-16.96%	92.6%
Total Long-Term Assets	$8.874B	$9.443B	$9.443B
YoY Change	-6.03%	137.26%	34.36%
TOTAL ASSETS
Total Short-Term Assets	$6.028B	$3.088B	$3.088B
Total Long-Term Assets	$8.874B	$9.443B	$9.443B
Total Assets	$14.90B	$12.53B	$12.53B
YoY Change	18.92%	17.91%	17.91%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$649.0M	$722.0M	$722.0M
YoY Change	-10.11%	-16.34%	-16.34%
Accrued Expenses	$747.0M	$736.0M	$736.0M
YoY Change	1.49%	8.24%	8.24%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$1.000M	$88.00M	$88.00M
YoY Change	-98.86%	22.22%	22.22%
Total Short-Term Liabilities	$1.915B	$2.359B	$2.359B
YoY Change	-18.82%	-1.63%	-1.63%
LONG-TERM LIABILITIES
Long-Term Debt	$8.691B	$5.803B	$5.803B
YoY Change	49.77%	-10.02%	-10.02%
Other Long-Term Liabilities	$2.597B	$1.084B	$2.674B
YoY Change	-2.88%	-14.91%	-8.77%
Total Long-Term Liabilities	$11.29B	$8.494B	$8.477B
YoY Change	33.16%	-10.07%	-9.63%
TOTAL LIABILITIES
Total Short-Term Liabilities	$1.915B	$2.359B	$2.359B
Total Long-Term Liabilities	$11.29B	$8.494B	$8.477B
Total Liabilities	$13.22B	$10.85B	$10.87B
YoY Change	21.6%	-8.36%	-8.34%
SHAREHOLDERS EQUITY
Retained Earnings		-$1.616B
YoY Change		-73.17%
Common Stock		$8.505B
YoY Change		-0.11%
Preferred Stock
YoY Change
Treasury Stock (at cost)		$5.039B
YoY Change		38.74%
Treasury Stock Shares		172.9M shares
Shareholders Equity	$1.680B	$1.658B	$1.658B
YoY Change
Total Liabilities & Shareholders Equity	$14.90B	$12.53B	$12.53B
YoY Change	18.92%	17.91%	17.91%

Cashflow Statement

Concept	2020	2019 Q4	2019
OPERATING ACTIVITIES
Net Income	$510.0M	$3.385B	$4.438B
YoY Change	-88.51%	-26138.46%	1555.97%
Depreciation, Depletion And Amortization	$435.0M	$134.0M	$373.0M
YoY Change	16.62%	48.89%	-11.4%
Cash From Operating Activities	$1.837B	$516.0M	$1.413B
YoY Change	30.01%	159.3%	2.61%
INVESTING ACTIVITIES
Capital Expenditures	$230.0M	-$45.00M	$228.0M
YoY Change	0.88%	4.65%	-41.24%
Acquisitions			$355.0M
YoY Change			46.09%
Other Investing Activities	$0.00	-$13.00M	-$6.000M
YoY Change	-100.0%	-87.38%	-200.0%
Cash From Investing Activities	-$494.0M	-$58.00M	$556.0M
YoY Change	-188.85%	-60.27%	-371.22%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net	$228.0M		$1.437B
YoY Change	-84.13%		16.92%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	$2.204B	-350.0M	-$2.148B
YoY Change	-202.61%	-59.3%	40.76%
NET CHANGE
Cash From Operating Activities	$1.837B	516.0M	$1.413B
Cash From Investing Activities	-$494.0M	-58.00M	$556.0M
Cash From Financing Activities	$2.204B	-350.0M	-$2.148B
Net Change In Cash	$3.545B	108.0M	-$228.0M
YoY Change	-1654.82%	-113.38%	-51.8%
FREE CASH FLOW
Cash From Operating Activities	$1.837B	$516.0M	$1.413B
Capital Expenditures	$230.0M	-$45.00M	$228.0M
Free Cash Flow	$1.607B	$561.0M	$1.185B
YoY Change	35.61%	131.82%	19.82%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020	dei	Entity Central Index Key EntityCentralIndexKey	0001013871
CY2020	dei	Amendment Flag AmendmentFlag	false
CY2020	dei	Document Fiscal Year Focus DocumentFiscalYearFocus	2020
CY2020	dei	Document Fiscal Period Focus DocumentFiscalPeriodFocus	FY
CY2020	nrg	Period Beyondwhich Comapny Can Not Predict Holdingof Collateral PeriodBeyondwhichComapnyCanNotPredictHoldingofCollateral	P12M
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
CY2020	nrg	Estimated Counterparty Credit Risk Exposure To Certain Counterparties Period EstimatedCounterpartyCreditRiskExposureToCertainCounterpartiesPeriod	P5Y
CY2020	nrg	Periodofretrospectivepremiumadjustments Periodofretrospectivepremiumadjustments	P24M
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	Entity Interactive Data Current EntityInteractiveDataCurrent	Yes
CY2020	dei	Document Transition Report DocumentTransitionReport	false
CY2020	dei	Entity File Number EntityFileNumber	001-15891
CY2020	dei	Entity Registrant Name EntityRegistrantName	NRG Energy, Inc
CY2020	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	41-1724239
CY2020	dei	Entity Address Address Line1 EntityAddressAddressLine1	804 Carnegie Center
CY2020	dei	Entity Address City Or Town EntityAddressCityOrTown	Princeton
CY2020	dei	Entity Address State Or Province EntityAddressStateOrProvince	NJ
CY2020	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	08540
CY2020	dei	City Area Code CityAreaCode	609
CY2020	dei	Local Phone Number LocalPhoneNumber	524-4500
CY2020	dei	Security12b Title Security12bTitle	Common Stock, par value $0.01
CY2020	dei	Trading Symbol TradingSymbol	NRG
CY2020	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020	dei	Entity Well Known Seasoned Issuer EntityWellKnownSeasonedIssuer	Yes
CY2020	dei	Entity Voluntary Filers EntityVoluntaryFilers	No
CY2020	dei	Entity Current Reporting Status EntityCurrentReportingStatus	Yes
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	421000000	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	75000000	USD
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	6941658699	USD
CY2021Q1	dei	Entity Common Stock Shares Outstanding EntityCommonStockSharesOutstanding	244687907	shares
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CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	5000000	USD
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CY2020	us-gaap	Restructuring Costs RestructuringCosts	0	USD
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CY2020	us-gaap	Interest Expense InterestExpense	401000000	USD
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CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	1105000000	USD
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CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-515000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	761000000	USD
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CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	4120000000	USD
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CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
CY2020	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	0	USD
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CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	262000000	shares
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CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-19000000	USD
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CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	78000000	USD
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CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-14000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-98000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-22000000	USD
CY2020	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	496000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	4343000000	USD
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CY2020	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	0	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	3000000	USD
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CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	8000000	USD
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CY2019Q4	us-gaap	Inventory Net InventoryNet	383000000	USD
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CY2019Q4	us-gaap	Derivative Instruments And Hedges DerivativeInstrumentsAndHedges	860000000	USD
CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	50000000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	190000000	USD
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CY2019Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	322000000	USD
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CY2019Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	8494000000	USD
CY2020Q4	us-gaap	Liabilities Liabilities	13222000000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	10853000000	USD
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CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2020Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	423057848	shares
CY2019Q4	us-gaap	Common Stock Shares Issued CommonStockSharesIssued	421890790	shares
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CY2020Q4	us-gaap	Treasury Stock Value TreasuryStockValue	5232000000	USD
CY2019Q4	us-gaap	Treasury Stock Value TreasuryStockValue	5039000000	USD
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CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1680000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1658000000	USD
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CY2020	nrg	Amortization Of Nuclear Fuel AmortizationOfNuclearFuel	54000000	USD
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CY2020	us-gaap	Share Based Compensation ShareBasedCompensation	22000000	USD
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CY2020	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	23000000	USD
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CY2018	nrg	Changes In Nuclear Decommissioning Trust Liability ChangesInNuclearDecommissioningTrustLiability	60000000	USD
CY2020	nrg	Oil Inventory Lower Of Cost Or Market Adjustment OilInventoryLowerOfCostOrMarketAdjustment	29000000	USD
CY2019	nrg	Oil Inventory Lower Of Cost Or Market Adjustment OilInventoryLowerOfCostOrMarketAdjustment	0	USD
CY2018	nrg	Oil Inventory Lower Of Cost Or Market Adjustment OilInventoryLowerOfCostOrMarketAdjustment	2000000	USD
CY2020	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	0	USD
CY2019	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	0	USD
CY2018	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	63000000	USD
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CY2019	us-gaap	Deconsolidation Gain Or Loss Amount DeconsolidationGainOrLossAmount	0	USD
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CY2020	us-gaap	Proceeds From Sale Of Other Productive Assets ProceedsFromSaleOfOtherProductiveAssets	81000000	USD
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CY2020	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	USD
CY2019	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	USD
CY2018	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	268000000	USD
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CY2020	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	0	USD
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CY2020	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	-494000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	558000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	520000000	USD
CY2020	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	0	USD
CY2019	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-2000000	USD
CY2018	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-725000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-494000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	556000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-205000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	3234000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	1833000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Senior Long Term Debt ProceedsFromIssuanceOfSeniorLongTermDebt	1100000000	USD
CY2019	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	3000000	USD
CY2020	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	335000000	USD
CY2019	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	2571000000	USD
CY2018	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1734000000	USD
CY2020	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	-83000000	USD
CY2019	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	83000000	USD
CY2018	us-gaap	Proceeds From Repayments Of Lines Of Credit ProceedsFromRepaymentsOfLinesOfCredit	0	USD
CY2020	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	75000000	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	35000000	USD
CY2018	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	19000000	USD
CY2020	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	295000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32000000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	37000000	USD
CY2020	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	229000000	USD
CY2019	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1440000000	USD
CY2018	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	1250000000	USD
CY2020	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	5000000	USD
CY2019	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	26000000	USD
CY2018	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	32000000	USD
CY2020	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-2000000	USD
CY2019	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-2000000	USD
CY2018	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-16000000	USD
CY2020	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	1000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	3000000	USD
CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	21000000	USD
CY2020	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	0	USD
CY2019	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	0	USD
CY2018	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	26000000	USD
CY2020	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-7000000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-4000000	USD
CY2018	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-4000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	2204000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-2191000000	USD
CY2018	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	7000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-1997000000	USD
CY2020	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	0	USD
CY2019	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	43000000	USD
CY2018	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	471000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	2204000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2148000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1526000000	USD
CY2020	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	-2000000	USD
CY2019	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	0	USD
CY2018	us-gaap	Effect Of Exchange Rate On Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations EffectOfExchangeRateOnCashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1000000	USD
CY2020	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	0	USD
CY2019	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	49000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	120000000	USD
CY2020	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	3545000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-228000000	USD
CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-473000000	USD
CY2019	nrg	Cost Of Services Energy Services Unbilled CostOfServicesEnergyServicesUnbilled	103000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	385000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	613000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1086000000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	3930000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	385000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	613000000	USD
CY2017Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1968000000	USD
CY2018	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	294000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-22000000	USD
CY2018	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	2000000	USD
CY2018	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	1250000000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	6000000	USD
CY2018	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	21000000	USD
CY2018	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	37000000	USD
CY2018	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	43000000	USD
CY2018	nrg	Noncontrolling Interest Contributionsfrom Noncontrolling Interest Holders NoncontrollingInterestContributionsfromNoncontrollingInterestHolders	304000000	USD
CY2018	us-gaap	Noncontrolling Interest Decrease From Deconsolidation NoncontrollingInterestDecreaseFromDeconsolidation	2548000000	USD
CY2018	us-gaap	Adjustments To Additional Paid In Capital Equity Component Of Convertible Debt AdjustmentsToAdditionalPaidInCapitalEquityComponentOfConvertibleDebt	101000000	USD
CY2018Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	-1234000000	USD
CY2019	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	4438000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-98000000	USD
CY2019	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	3000000	USD
CY2019	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	1409000000	USD
CY2019	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	-16000000	USD
CY2019	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	6000000	USD
CY2019	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	32000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1658000000	USD
CY2020	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	510000000	USD
CY2020	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-14000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Other AdjustmentsToAdditionalPaidInCapitalOther	18000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Other AdjustmentsToAdditionalPaidInCapitalOther	18000000	USD
CY2020	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	4000000	USD
CY2020	us-gaap	Treasury Stock Value Acquired Cost Method TreasuryStockValueAcquiredCostMethod	197000000	USD
CY2020	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	-3000000	USD
CY2020	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	1000000	USD
CY2020	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	297000000	USD
CY2020Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1680000000	USD
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.20
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2020	us-gaap	Nature Of Operations NatureOfOperations	<span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Nature of Business</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%"> </span><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">General</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">NRG Energy, Inc., or NRG or the Company, is an integrated power company built on dynamic retail brands with diverse generation assets. NRG brings the power of energy to customers by producing and selling energy and related products and services in major competitive power and gas markets in the U.S. and Canada in a manner that delivers value to all of NRG's stakeholders. NRG is a customer-centric business focused on perfecting the integrated model by balancing retail load with generation supply within its deregulated markets. As of December 31, 2020, the Company sold energy, services, and innovative, sustainable products and services directly to retail customers under the names NRG, Reliant, Green Mountain Energy, Stream and XOOM Energy, as well as other brand names owned by NRG, supported by approximately 23,000 MW of generation.</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">NRG also conducts business under the brand name of Direct Energy as a result of the Company's acquisition of Direct Energy, a North American subsidiary of Centrica plc, on January 5, 2021. Direct Energy is a leading retail provider of electricity, natural gas, and home and business energy related products and services in North America, with operations in all 50 U.S. states and 8 Canadian provinces. Following the acquisition, the Company serves more than 6 million customers. In addition, Direct Energy is a participant in the wholesale gas and power markets in the United States and Canada. Note 4, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Acquisitions, Discontinued Operations and Dispositions</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> for further discussion of the acquisition of Direct Energy.</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company began managing its integrated model based on the combined results of the retail and wholesale generation businesses with a geographical focus in 2020. As a result, the Company changed its business segments from Retail and Generation to Texas, East and West/Other beginning in the first quarter of 2020. The Company's updated segment structure reflects how management makes financial decisions and allocates resources. </span></div><div style="margin-bottom:3pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">The Company's businesses are segregated as follows: </span></div><div style="margin-bottom:3pt;padding-left:36pt;text-align:justify;text-indent:-13.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%;padding-left:9.3pt">Texas, which includes all activity related to customer, plant and market operations in Texas; </span></div><div style="margin-bottom:3pt;padding-left:36pt;text-align:justify;text-indent:-13.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%;padding-left:9.3pt">East, which includes the remaining activity related to customer operations and all activity related to plant and market operations in the East; </span></div><div style="margin-bottom:3pt;padding-left:36pt;text-align:justify;text-indent:-13.5pt"><span style="color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%;padding-left:9.3pt">West/Other, which includes the following assets and activities: (i) all activity related to plant and market operations in the West, (ii) activity related to the Cottonwood power plant that was sold to Cleco on February 4, 2019 and is being leased back until 2025, (iii) the remaining renewables activity, including the Company’s equity method investments in Ivanpah Master Holdings, LLC and Agua Caliente (which was sold on February 3, 2021), the remaining Home Solar assets (which were primarily sold on November 13, 2020) and the NFL stadium solar generating assets, and (iv) activity related to the Company’s equity method investment for the Gladstone power plant in Australia; and</span></div><div style="margin-bottom:6pt;padding-left:36pt;text-align:justify;text-indent:-13.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">•</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%;padding-left:10pt">Corporate activities. </span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">All affected disclosures presented herein have been recast to reflect these changes for all periods presented. For further discussion of segment reporting, refer to Note 20, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:115%">Segment Reporting</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">.</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%">The acquired operations of Direct Energy will be integrated into the existing NRG segment structure. Domestic customer and market operations will be combined into the corresponding geographical segments of Texas, East and West/Other. The East segment will also include the deregulated customer and market operations of Canada. The West/Other segment will also include activity related to the regulated operations in Alberta, Canada and the services businesses. </span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">COVID-19</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In March 2020, the World Health Organization categorized COVID-19 as a pandemic and the President of the United States declared the COVID-19 outbreak a national emergency. Electricity was deemed a 'critical and essential business operation' under various state and federal governmental COVID-19 mandates. NRG had activated its Crisis Management Team ("CMT") in January 2020 to proactively manage the Company's response to the impacts of COVID-19. </span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">NRG continues to remain focused on protecting the health and well-being of its employees, while supporting its customers and the communities in which it operates and assuring the continuity of its operations. In June 2020, summer-critical office employees returned to the offices and safety protocols were successfully implemented. </span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The Company continues to maintain certain restrictions on business travel and face-to-face sales channels, remote work practices remain in place and there are enhanced cleaning and hygiene protocols in all of its facilities. In addition, select essential employees and contractors are continuing to report to plant and certain office locations. The Company also continues to require pre-entry screening, including temperature checks, separation of work crews, additional personal protective </span></div><div style="margin-bottom:6pt;text-align:justify"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">equipment for employees and contractors when social distancing cannot be maintained, and a ban on all non-essential visitors. The Company has not experienced any material disruptions in its ability to continue its business operations to date.</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The first COVID-19 vaccine became available in the United States in December 2020. NRG continues to advocate alongside state and federal trade groups for the high prioritization of essential electric industry personnel for inoculation against COVID-19. States are receiving weekly doses of vaccines and allocating those doses to frontline healthcare workers, elderly populations and high risk individuals. NRG continues to monitor state information, as well as dosage and allocation numbers to anticipate the latest timing of vaccine distribution to our essential employees. The Company will continue to evaluate additional return to normal work operations on a location-by-location basis as COVID-19 conditions evolve. </span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Discontinued Operations</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On December 31, 2018, as described in Note 4, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Acquisitions, Discontinued Operations and Dispositions</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">, the Company concluded that the sale of its South Central Portfolio to Cleco, excluding the Cottonwood facility, met held-for-sale criteria and should be presented as a discontinued operation, as the sale represented a strategic shift in the business in which NRG operates. The financial information for all historical periods was recast in 2018 to reflect the presentation of these entities as discontinued operations.</span></div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">On August 31, 2018, as described in Note 4, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Acquisitions, Discontinued Operations and Dispositions</span>, the Company deconsolidated NRG Yield, Inc. and its Renewables Platform for financial reporting purposes. The financial information for all historical periods was recast in 2018 to reflect the presentation of these entities, as well as the Carlsbad project, as discontinued operations. As a result of the sale of NRG Yield, the Company no longer controls the Agua Caliente project. Due to this change in control, the Company deconsolidated the Agua Caliente project from its financial results and began accounting for the project as an equity method investment.
CY2020Q4	nrg	Power Generation Capacity Megawatts PowerGenerationCapacityMegawatts	23000	MW
CY2020	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	510000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	4117000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	465000000	USD
CY2020	nrg	Income Loss From Discontinued Operations Including Adjustment For Discontinued Operations Noncontrolling Interest Net Of Tax Attributable To Parent IncomeLossFromDiscontinuedOperationsIncludingAdjustmentForDiscontinuedOperationsNoncontrollingInterestNetOfTaxAttributableToParent	0	USD
CY2019	nrg	Income Loss From Discontinued Operations Including Adjustment For Discontinued Operations Noncontrolling Interest Net Of Tax Attributable To Parent IncomeLossFromDiscontinuedOperationsIncludingAdjustmentForDiscontinuedOperationsNoncontrollingInterestNetOfTaxAttributableToParent	321000000	USD
CY2018	nrg	Income Loss From Discontinued Operations Including Adjustment For Discontinued Operations Noncontrolling Interest Net Of Tax Attributable To Parent IncomeLossFromDiscontinuedOperationsIncludingAdjustmentForDiscontinuedOperationsNoncontrollingInterestNetOfTaxAttributableToParent	-197000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	510000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	nrg	Cost Of Services Energy Services Unbilled CostOfServicesEnergyServicesUnbilled	105000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	43000000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	108000000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Write Offs AllowanceForDoubtfulAccountsReceivableWriteOffs	101000000	USD
CY2020	us-gaap	Allowance For Doubtful Accounts Receivable Recoveries AllowanceForDoubtfulAccountsReceivableRecoveries	17000000	USD
CY2020Q4	us-gaap	Allowance For Doubtful Accounts Receivable AllowanceForDoubtfulAccountsReceivable	67000000	USD
CY2020Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	3905000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	345000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	563000000	USD
CY2020Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	19000000	USD
CY2019Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	32000000	USD
CY2018Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	33000000	USD
CY2020Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	6000000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	8000000	USD
CY2018Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	17000000	USD
CY2020Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	3930000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	385000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	613000000	USD
CY2020	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	2000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1400000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1300000000	USD
CY2020Q4	us-gaap	Lessor Operating Lease Term Of Contract LessorOperatingLeaseTermOfContract	P20Y
CY2018	us-gaap	Operating Leases Income Statement Contingent Revenue OperatingLeasesIncomeStatementContingentRevenue	104000000	USD
CY2020	nrg	Gross Receipts Tax GrossReceiptsTax	107000000	USD
CY2019	nrg	Gross Receipts Tax GrossReceiptsTax	109000000	USD
CY2018	nrg	Gross Receipts Tax GrossReceiptsTax	99000000	USD
CY2020	nrg	Cost Of Services Energy Services Unbilled CostOfServicesEnergyServicesUnbilled	98000000	USD
CY2020Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-2000000	USD
CY2019Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-13000000	USD
CY2018Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-13000000	USD
CY2020	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Concentrations of Credit Risk</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Financial instruments which potentially subject the Company to concentrations of credit risk consist primarily of trust funds, accounts receivable, notes receivable, derivatives, and investments in debt securities. Trust funds are held in accounts managed by experienced investment advisors. Certain accounts receivable, notes receivable, and derivative instruments are concentrated within entities engaged in the energy industry. These industry concentrations may impact the Company's overall exposure to credit risk, either positively or negatively, in that the customers may be similarly affected by changes in economic, industry or other conditions. Receivables and other contractual arrangements are subject to collateral requirements under the </span></div><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">terms of enabling agreements. However, the Company believes that the credit risk posed by industry concentration is offset by the diversification and creditworthiness of its customer base. See Note 5, </span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:400;line-height:120%">Fair Value of Financial Instruments,</span><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%"> for a further discussion of derivative concentrations.</span>
CY2018	us-gaap	Advertising Expense AdvertisingExpense	73000000	USD
CY2017Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	78000000	USD
CY2018	nrg	Redeemable Noncontrolling Interest Cash Contributionsfrom Noncontrolling Interest Holders RedeemableNoncontrollingInterestCashContributionsfromNoncontrollingInterestHolders	26000000	USD
CY2018	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	1000000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Noncontrolling Interest IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToNoncontrollingInterest	-27000000	USD
CY2018Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	19000000	USD
CY2019	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	3000000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	20000000	USD
CY2020	us-gaap	Minority Interest Decrease From Redemptions MinorityInterestDecreaseFromRedemptions	20000000	USD
CY2020Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	0	USD
CY2020	us-gaap	Advertising Expense AdvertisingExpense	74000000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	66000000	USD
CY2020	us-gaap	Restructuring Costs RestructuringCosts	0	USD
CY2019	us-gaap	Restructuring Costs RestructuringCosts	23000000	USD
CY2018	us-gaap	Restructuring Costs RestructuringCosts	90000000	USD
CY2020	us-gaap	Use Of Estimates UseOfEstimates	<div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Use of Estimates</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">The preparation of financial statements in conformity with accounting principles generally accepted in the United States requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities at the date of the financial statements, disclosure of contingent assets and liabilities at the date of the financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from these estimates. </span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">In recording transactions and balances resulting from business operations, the Company uses estimates based on the best information available. Estimates are used for such items as plant depreciable lives, tax provisions, uncollectible accounts, actuarially determined benefit costs, the valuation of energy commodity contracts, environmental liabilities, legal costs incurred in connection with recorded loss contingencies, and assets acquired and liabilities assumed in business combinations, among others. In addition, estimates are used to test long-lived assets and goodwill for impairment and to determine the fair value of impaired assets. As better information becomes available or actual amounts are determinable, the recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates.</span></div>
CY2020	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-style:italic;font-weight:700;line-height:120%">Reclassifications</span></div><div style="margin-bottom:6pt;text-align:justify;text-indent:22.5pt"><span style="color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%">Certain prior year amounts have been reclassified for comparative purposes. The reclassifications did not affect results from operations, net assets or cash flows.</span></div>
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	668000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	289000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	47000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	36000000	USD
CY2020Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	20000000	USD
CY2020	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	18000000	USD
CY2020	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	8690000000	USD
CY2019	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	20000000	USD
CY2019	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	7991000000	USD
CY2018	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	21000000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	8148000000	USD
CY2020Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	113000000	USD
CY2019Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	133000000	USD
CY2020Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	904000000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	1025000000	USD
CY2020Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	393000000	USD
CY2019Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	402000000	USD
CY2020Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	60000000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	82000000	USD
CY2020	nrg	Contractwith Customer Liability Increase For Cash Payments Received ContractwithCustomerLiabilityIncreaseForCashPaymentsReceived	31000000	USD
CY2019	nrg	Contractwith Customer Liability Increase For Cash Payments Received ContractwithCustomerLiabilityIncreaseForCashPaymentsReceived	24000000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	13000000	USD
CY2020	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	13000000	USD
CY2020	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	17000000	USD
CY2019Q3	us-gaap	Number Of States In Which Entity Operates NumberOfStatesInWhichEntityOperates	9	state
CY2020Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	50000000	USD
CY2020Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	25000000	USD
CY2020Q4	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	1000000	USD
CY2020Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	1745000000	USD
CY2020Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	884000000	USD
CY2019Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	20000000	USD
CY2019Q4	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	1000000	USD
CY2019Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	1993000000	USD
CY2019Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	1103000000	USD
CY2020Q4	nrg	Derivative Asset Fair Value Determined Using Valuation Techniques Percentage DerivativeAssetFairValueDeterminedUsingValuationTechniquesPercentage	0.17
CY2020Q4	nrg	Derivative Liability Fair Value Determined Using Valuation Techniques Percentage DerivativeLiabilityFairValueDeterminedUsingValuationTechniquesPercentage	0.18
CY2020	nrg	Increase In Credit Reserve Increase In Cost Of Revenue IncreaseInCreditReserveIncreaseInCostOfRevenue	2000000	USD
CY2020Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	19000000	USD
CY2020Q4	nrg	Amount Of Credit Exposure To Significant Portion Of All Counterparties AmountOfCreditExposureToSignificantPortionOfAllCounterparties	210000000	USD
CY2020Q4	nrg	Collateral Held Cash And Letters Of Credit CollateralHeldCashAndLettersOfCredit	14000000	USD
CY2020Q4	nrg	Net Credit Exposure NetCreditExposure	204000000	USD
CY2020	nrg	Counterparty Credit Risk Exposure Percentage Of Credit Risk Roll Off CounterpartyCreditRiskExposurePercentageOfCreditRiskRollOff	0.54
CY2020Q4	nrg	Credit Derivative Maximum Net Exposure Percentage CreditDerivativeMaximumNetExposurePercentage	1
CY2020Q4	nrg	Credit Derivative Maximum Net Exposure Percentage CreditDerivativeMaximumNetExposurePercentage	1
CY2020Q4	nrg	Number Of Wholesale Counterparties With Credit Risk Exposure NumberOfWholesaleCounterpartiesWithCreditRiskExposure	47000000	counterparty
CY2020	nrg	Counterparty Credit Risk Exposure Percentage Threshold CounterpartyCreditRiskExposurePercentageThreshold	0.10
CY2020	nrg	Estimated Counterparty Credit Risk Exposure To Certain Counterparties EstimatedCounterpartyCreditRiskExposureToCertainCounterparties	645000000	USD
CY2020	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	108000000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	95000000	USD
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	85000000	USD
CY2018	nrg	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Divestiture Of Business Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIDivestitureOfBusinessNetOfTax	25000000	USD
CY2020	nrg	Reversal Previously Recognized Unrealized Gains Losses Settled Positions Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesSettledPositionsEconomicHedges	55000000	USD
CY2019	nrg	Reversal Previously Recognized Unrealized Gains Losses Settled Positions Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesSettledPositionsEconomicHedges	68000000	USD
CY2018	nrg	Reversal Previously Recognized Unrealized Gains Losses Settled Positions Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesSettledPositionsEconomicHedges	73000000	USD
CY2020	nrg	Reversal Previously Recognized Unrealized Gains Losses Acquiredas Partof Acquisition Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesAcquiredasPartofAcquisitionEconomicHedges	-4000000	USD
CY2019	nrg	Reversal Previously Recognized Unrealized Gains Losses Acquiredas Partof Acquisition Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesAcquiredasPartofAcquisitionEconomicHedges	-6000000	USD
CY2018	nrg	Reversal Previously Recognized Unrealized Gains Losses Acquiredas Partof Acquisition Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesAcquiredasPartofAcquisitionEconomicHedges	10000000	USD
CY2020	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	-68000000	USD
CY2019	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	42000000	USD
CY2018	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	97000000	USD
CY2020	nrg	Unrealized Gain Loss On Derivatives Mark To Market Economic Hedging Activities UnrealizedGainLossOnDerivativesMarkToMarketEconomicHedgingActivities	-119000000	USD
CY2019	nrg	Unrealized Gain Loss On Derivatives Mark To Market Economic Hedging Activities UnrealizedGainLossOnDerivativesMarkToMarketEconomicHedgingActivities	-20000000	USD
CY2018	nrg	Unrealized Gain Loss On Derivatives Mark To Market Economic Hedging Activities UnrealizedGainLossOnDerivativesMarkToMarketEconomicHedgingActivities	14000000	USD
CY2020	nrg	Reversal Previously Unrecognized Unrealized Gains Losses Settled Positions Trading Activity ReversalPreviouslyUnrecognizedUnrealizedGainsLossesSettledPositionsTradingActivity	20000000	USD
CY2019	nrg	Reversal Previously Unrecognized Unrealized Gains Losses Settled Positions Trading Activity ReversalPreviouslyUnrecognizedUnrealizedGainsLossesSettledPositionsTradingActivity	11000000	USD
CY2018	nrg	Reversal Previously Unrecognized Unrealized Gains Losses Settled Positions Trading Activity ReversalPreviouslyUnrecognizedUnrealizedGainsLossesSettledPositionsTradingActivity	12000000	USD
CY2020	nrg	Derivative Unrealized Gains On Open Positions Related To Trading Activity Net DerivativeUnrealizedGainsOnOpenPositionsRelatedToTradingActivityNet	15000000	USD
CY2019	nrg	Derivative Unrealized Gains On Open Positions Related To Trading Activity Net DerivativeUnrealizedGainsOnOpenPositionsRelatedToTradingActivityNet	31000000	USD
CY2018	nrg	Derivative Unrealized Gains On Open Positions Related To Trading Activity Net DerivativeUnrealizedGainsOnOpenPositionsRelatedToTradingActivityNet	29000000	USD
CY2020	nrg	Unrealized Gain Losson Derivatives Mark To Market Trading Activities UnrealizedGainLossonDerivativesMarkToMarketTradingActivities	-5000000	USD
CY2019	nrg	Unrealized Gain Losson Derivatives Mark To Market Trading Activities UnrealizedGainLossonDerivativesMarkToMarketTradingActivities	20000000	USD
CY2018	nrg	Unrealized Gain Losson Derivatives Mark To Market Trading Activities UnrealizedGainLossonDerivativesMarkToMarketTradingActivities	17000000	USD
CY2020	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	-124000000	USD
CY2019	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	USD
CY2018	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	31000000	USD
CY2020	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	-68000000	USD
CY2019	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	42000000	USD
CY2018	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	97000000	USD
CY2020Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	35000000	USD
CY2020Q4	us-gaap	Additional Collateral Aggregate Fair Value AdditionalCollateralAggregateFairValue	1000000	USD
CY2020Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	890000000	USD
CY2020	nrg	Decommissioning Fund Investments Unrealized Gains DecommissioningFundInvestmentsUnrealizedGains	398000000	USD
CY2020	nrg	Decommissioning Fund Investments Unrealized Loss DecommissioningFundInvestmentsUnrealizedLoss	0	USD
CY2019Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	794000000	USD
CY2019	nrg	Decommissioning Fund Investments Unrealized Gains DecommissioningFundInvestmentsUnrealizedGains	338000000	USD
CY2019	nrg	Decommissioning Fund Investments Unrealized Loss DecommissioningFundInvestmentsUnrealizedLoss	1000000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	34000000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	18000000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	17000000	USD
CY2020	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	13000000	USD
CY2019	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	9000000	USD
CY2018	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	13000000	USD
CY2020	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	439000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	381000000	USD
CY2018	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	513000000	USD
CY2020Q4	us-gaap	Energy Related Inventory Petroleum EnergyRelatedInventoryPetroleum	37000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Petroleum EnergyRelatedInventoryPetroleum	73000000	USD
CY2020Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	73000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	93000000	USD
CY2020Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	22000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	21000000	USD
CY2020Q4	us-gaap	Other Inventories Spare Parts OtherInventoriesSpareParts	195000000	USD
CY2019Q4	us-gaap	Other Inventories Spare Parts OtherInventoriesSpareParts	196000000	USD
CY2020Q4	us-gaap	Inventory Net InventoryNet	327000000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	383000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	4483000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	4345000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1936000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1752000000	USD
CY2020Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	2547000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	2593000000	USD
CY2020	us-gaap	Depreciation Depreciation	295000000	USD
CY2019	us-gaap	Depreciation Depreciation	271000000	USD
CY2018	us-gaap	Depreciation Depreciation	356000000	USD
CY2020	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	3000000	USD
CY2019	us-gaap	Finance Lease Right Of Use Asset Amortization FinanceLeaseRightOfUseAssetAmortization	0	USD
CY2020	us-gaap	Operating Lease Cost OperatingLeaseCost	100000000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	109000000	USD
CY2020	us-gaap	Short Term Lease Cost ShortTermLeaseCost	3000000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	3000000	USD
CY2020	us-gaap	Variable Lease Cost VariableLeaseCost	6000000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	6000000	USD
CY2020	us-gaap	Sublease Income SubleaseIncome	17000000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	17000000	USD
CY2020	us-gaap	Lease Cost LeaseCost	95000000	USD
CY2019	us-gaap	Lease Cost LeaseCost	101000000	USD
CY2020	us-gaap	Operating Lease Payments OperatingLeasePayments	101000000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	104000000	USD
CY2020	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	1000000	USD
CY2019	us-gaap	Finance Lease Principal Payments FinanceLeasePrincipalPayments	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	5000000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Finance Lease Liability RightOfUseAssetObtainedInExchangeForFinanceLeaseLiability	0	USD
CY2020	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	4000000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	215000000	USD
CY2020Q4	us-gaap	Finance Lease Weighted Average Remaining Lease Term1 FinanceLeaseWeightedAverageRemainingLeaseTerm1	P1Y1M6D
CY2020Q4	us-gaap	Finance Lease Weighted Average Discount Rate Percent FinanceLeaseWeightedAverageDiscountRatePercent	0.0479
CY2020Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P5Y3M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y9M18D
CY2020Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0563
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0572
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Next Twelve Months LesseeOperatingLeaseLiabilityPaymentsDueNextTwelveMonths	86000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	82000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	81000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	71000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	47000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	34000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	401000000	USD
CY2020Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	54000000	USD
CY2020Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	347000000	USD
CY2020	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	14000000	USD
CY2019	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	12000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	579000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	579000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	2051000000	USD
CY2020	nrg	Finite Lived Intangible Assets Purchases FiniteLivedIntangibleAssetsPurchases	70000000	USD
CY2020	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	22000000	USD
CY2020	nrg	Finite Lived Intangible Assets Usage And Retirements FiniteLivedIntangibleAssetsUsageAndRetirements	35000000	USD
CY2020	nrg	Finite Lived Intangible Assets Write Off Of Fully Amortized Intangible Assets FiniteLivedIntangibleAssetsWriteOffOfFullyAmortizedIntangibleAssets	74000000	USD
CY2020	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	14000000	USD
CY2020	nrg	Finite Lived Intangible Assets Other Changes FiniteLivedIntangibleAssetsOtherChanges	5000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	2025000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1357000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	668000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	1742000000	USD
CY2019	nrg	Finite Lived Intangible Assets Purchases FiniteLivedIntangibleAssetsPurchases	42000000	USD
CY2019	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	318000000	USD
CY2019	nrg	Finite Lived Intangible Assets Usage And Retirements FiniteLivedIntangibleAssetsUsageAndRetirements	21000000	USD
CY2019	nrg	Finite Lived Intangible Assets Write Off Of Fully Amortized Intangible Assets FiniteLivedIntangibleAssetsWriteOffOfFullyAmortizedIntangibleAssets	30000000	USD
CY2019	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	2000000	USD
CY2019	nrg	Finite Lived Intangible Assets Other Changes FiniteLivedIntangibleAssetsOtherChanges	2000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	2051000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1262000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	789000000	USD
CY2020	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	204000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	151000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	133000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	149000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	128000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	127000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	91000000	USD
CY2020Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	70000000	USD
CY2020Q4	us-gaap	Long Term Debt LongTermDebt	8855000000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	6042000000	USD
CY2020Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	4000000	USD
CY2019Q4	us-gaap	Finance Lease Liability FinanceLeaseLiability	0	USD
CY2020Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	8859000000	USD
CY2019Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	6042000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	1000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	88000000	USD
CY2020Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	93000000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	65000000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	74000000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	86000000	USD
CY2020Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	8691000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	5803000000	USD
CY2020Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	74000000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	86000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	1000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	2000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	1000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	600000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	500000000	USD
CY2020Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	7755000000	USD
CY2020Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	8859000000	USD
CY2019Q2	nrg	Increase Decrease In Long Term Debt IncreaseDecreaseInLongTermDebt	-594000000	USD
CY2020Q4	nrg	Put Option Agreement Semi Annual Interest Rate PutOptionAgreementSemiAnnualInterestRate	0.0165
CY2020Q4	nrg	Put Option Agreement Covenant Mandatory Exercise Of Issuance Right Consolidated Stockholders Equity Minimum PutOptionAgreementCovenantMandatoryExerciseOfIssuanceRightConsolidatedStockholdersEquityMinimum	2000000000.0	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	728000000	USD
CY2020	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	26000000	USD
CY2020	us-gaap	Costs Incurred Asset Retirement Obligation Incurred CostsIncurredAssetRetirementObligationIncurred	3000000	USD
CY2020	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	43000000	USD
CY2020	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	46000000	USD
CY2020Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	760000000	USD
CY2020Q4	nrg	Number Of Defined Benefit Plans NumberOfDefinedBenefitPlans	2	benefitPlan
CY2019Q3	us-gaap	Defined Benefit Plan Recognized Net Gain Loss Due To Curtailments DefinedBenefitPlanRecognizedNetGainLossDueToCurtailments	8000000	USD
CY2019Q3	us-gaap	Defined Benefit Plan Curtailments DefinedBenefitPlanCurtailments	-32000000	USD
CY2020	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	22000000	USD
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	22000000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	28000000	USD
CY2019Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2020Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2018Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2017Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2019Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2020Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2018Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2017Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2018	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	35234664	shares
CY2019	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	36301882	shares
CY2020	us-gaap	Stock Repurchased During Period Shares StockRepurchasedDuringPeriodShares	6062783	shares
CY2020	nrg	Common Stock Quarterly Dividends Per Share Cash Paid CommonStockQuarterlyDividendsPerShareCashPaid	0.30
CY2019	nrg	Common Stock Quarterly Dividends Per Share Cash Paid CommonStockQuarterlyDividendsPerShareCashPaid	0.03
CY2018	nrg	Common Stock Quarterly Dividends Per Share Cash Paid CommonStockQuarterlyDividendsPerShareCashPaid	0.03
CY2020	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	1.20
CY2019	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2018	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2020Q1	nrg	Common Stock Dividends Proposed Annual Amount Per Share CommonStockDividendsProposedAnnualAmountPerShare	1.20
CY2019	nrg	Common Stock Dividends Proposed Annual Amount Per Share CommonStockDividendsProposedAnnualAmountPerShare	0.12
CY2019Q4	nrg	Long Term Capital Allocation Target Allocation Cash Generated Allocated To Growth Investments Percentage LongTermCapitalAllocationTargetAllocationCashGeneratedAllocatedToGrowthInvestmentsPercentage	0.50
CY2019Q4	nrg	Long Term Capital Allocation Target Allocation Cash Generated Allocated Returned To Shareholders Percentage LongTermCapitalAllocationTargetAllocationCashGeneratedAllocatedReturnedToShareholdersPercentage	0.50
CY2019Q4	nrg	Long Term Capital Allocation Target Allocation Cash Generated Allocated Returned To Shareholders Percentage LongTermCapitalAllocationTargetAllocationCashGeneratedAllocatedReturnedToShareholdersPercentage	0.50
CY2019Q1	nrg	Employee Stock Purchase Plan Minimum Percentageof Compensation Eligible EmployeeStockPurchasePlanMinimumPercentageofCompensationEligible	0.01
CY2019Q1	nrg	Employee Stock Purchase Plan Maximum Percentage Of Compensation Eligible EmployeeStockPurchasePlanMaximumPercentageOfCompensationEligible	0.10
CY2019Q1	us-gaap	Share Based Compensation Arrangement By Share Based Payment Award Discount From Market Price Purchase Date ShareBasedCompensationArrangementByShareBasedPaymentAwardDiscountFromMarketPricePurchaseDate	0.95
CY2019Q1	nrg	Employee Stock Purchase Plan Exercise Price As Percentage Of Fair Value EmployeeStockPurchasePlanExercisePriceAsPercentageOfFairValue	0.95
CY2020	nrg	Employee Stock Purchase Plan Maximum Percentage Of Compensation Eligible EmployeeStockPurchasePlanMaximumPercentageOfCompensationEligible	0.10
CY2020	nrg	Employee Stock Purchase Plan Exercise Price As Percentage Of Fair Value EmployeeStockPurchasePlanExercisePriceAsPercentageOfFairValue	0.85
CY2020	nrg	Employee Stock Purchase Plan Exercise Price As Percentage Of Fair Value EmployeeStockPurchasePlanExercisePriceAsPercentageOfFairValue	0.85
CY2020Q4	nrg	Common Stock Capital Shares Reserved For Employee Stock Purchase Plan CommonStockCapitalSharesReservedForEmployeeStockPurchasePlan	2753591	shares
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	346000000	USD
CY2020Q4	us-gaap	Equity Method Investment Difference Between Carrying Amount And Underlying Equity EquityMethodInvestmentDifferenceBetweenCarryingAmountAndUnderlyingEquity	343000000	USD
CY2020Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	30000000	USD
CY2019Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	42000000	USD
CY2020Q4	us-gaap	Equity Method Investment Dividends Or Distributions EquityMethodInvestmentDividendsOrDistributions	50000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	510000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	245000000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	262000000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	304000000	shares
CY2020	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	2.08
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	16.94
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.88
CY2020	us-gaap	Net Income Loss NetIncomeLoss	510000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2020	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	245000000	shares
CY2019	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	262000000	shares
CY2018	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	304000000	shares
CY2020	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	1000000	shares
CY2019	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	2000000	shares
CY2018	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	4000000	shares
CY2020	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	246000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	264000000	shares
CY2019	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	264000000	shares
CY2018	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	308000000	shares
CY2020	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	2.07
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	16.81
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.87
CY2020	us-gaap	Revenues Revenues	9093000000	USD
CY2020	nrg	Costofrevenueincludingsellingmarketingandgeneraladministrative Costofrevenueincludingsellingmarketingandgeneraladministrative	7473000000	USD
CY2020	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	435000000	USD
CY2020	us-gaap	Asset Impairment Charges AssetImpairmentCharges	75000000	USD
CY2020	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	8000000	USD
CY2020	us-gaap	Costs And Expenses CostsAndExpenses	7991000000	USD
CY2020	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	3000000	USD
CY2020	us-gaap	Operating Income Loss OperatingIncomeLoss	1105000000	USD
CY2020	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	17000000	USD
CY2020	us-gaap	Impairment Of Investments ImpairmentOfInvestments	18000000	USD
CY2020	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	67000000	USD
CY2020	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-9000000	USD
CY2020	us-gaap	Interest Expense InterestExpense	401000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	761000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	251000000	USD
CY2020	us-gaap	Net Income Loss NetIncomeLoss	510000000	USD
CY2019	us-gaap	Costs And Expenses CostsAndExpenses	8538000000	USD
CY2019	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	7000000	USD
CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	1290000000	USD
CY2020Q4	us-gaap	Equity Method Investments EquityMethodInvestments	346000000	USD
CY2020Q4	nrg	Capital Expenditures CapitalExpenditures	230000000	USD
CY2020Q4	us-gaap	Goodwill Goodwill	579000000	USD
CY2020Q4	us-gaap	Assets Assets	14902000000	USD
CY2019	us-gaap	Revenues Revenues	9821000000	USD
CY2019	nrg	Costofrevenueincludingsellingmarketingandgeneraladministrative Costofrevenueincludingsellingmarketingandgeneraladministrative	8153000000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	373000000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	5000000	USD
CY2019	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	7000000	USD
CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	2000000	USD
CY2019	us-gaap	Impairment Of Investments ImpairmentOfInvestments	108000000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	66000000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-51000000	USD
CY2019	us-gaap	Interest Expense InterestExpense	413000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	786000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3334000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	4120000000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	321000000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	4441000000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	388000000	USD
CY2019Q4	nrg	Capital Expenditures CapitalExpenditures	228000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	579000000	USD
CY2019Q4	us-gaap	Assets Assets	12531000000	USD
CY2018	us-gaap	Revenues Revenues	9478000000	USD
CY2018	nrg	Costofrevenueincludingsellingmarketingandgeneraladministrative Costofrevenueincludingsellingmarketingandgeneraladministrative	7997000000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	421000000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	99000000	USD
CY2018	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	11000000	USD
CY2018	us-gaap	Costs And Expenses CostsAndExpenses	8528000000	USD
CY2018	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	32000000	USD
CY2018	us-gaap	Operating Income Loss OperatingIncomeLoss	982000000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	9000000	USD
CY2018	us-gaap	Impairment Of Investments ImpairmentOfInvestments	15000000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	18000000	USD
CY2018	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-44000000	USD
CY2018	us-gaap	Interest Expense InterestExpense	483000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	467000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	460000000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-192000000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	268000000	USD
CY2018	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	0	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2020	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	22000000	USD
CY2019	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	2000000	USD
CY2018	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	6000000	USD
CY2020	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	4000000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	4000000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	0	USD
CY2020	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	26000000	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6000000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6000000	USD
CY2020	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	168000000	USD
CY2019	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-3000000000	USD
CY2018	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-16000000	USD
CY2020	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	60000000	USD
CY2019	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-340000000	USD
CY2018	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	16000000	USD
CY2020	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	-3000000	USD
CY2019	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	0	USD
CY2018	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	1000000	USD
CY2020	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	225000000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-3340000000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	1000000	USD
CY2020	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	251000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3334000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	USD
CY2020	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.330
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-4.242
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.015
CY2019	us-gaap	Income Tax Reconciliation Change In Deferred Tax Assets Valuation Allowance IncomeTaxReconciliationChangeInDeferredTaxAssetsValuationAllowance	-3500000000	USD
CY2019	nrg	Net Operating Loss Carryforwards Utilized NetOperatingLossCarryforwardsUtilized	593000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	749000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	771000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	468000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	12000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	15000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	-1000000	USD
CY2020	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	761000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	786000000	USD
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CY2019Q4	us-gaap	Deferred Tax Assets Derivative Instruments DeferredTaxAssetsDerivativeInstruments	0	USD
CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Domestic DeferredTaxAssetsOperatingLossCarryforwardsDomestic	2117000000	USD
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CY2020Q4	us-gaap	Deferred Tax Assets Operating Loss Carryforwards Foreign DeferredTaxAssetsOperatingLossCarryforwardsForeign	102000000	USD
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CY2019Q4	us-gaap	Deferred Tax Assets Gross DeferredTaxAssetsGross	3800000000	USD
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CY2019Q4	nrg	Deferred Tax Liabilities Emissions Allowances DeferredTaxLiabilitiesEmissionsAllowances	19000000	USD
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CY2019Q4	us-gaap	Deferred Tax Liabilities Goodwill And Intangible Assets Goodwill DeferredTaxLiabilitiesGoodwillAndIntangibleAssetsGoodwill	8000000	USD
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CY2019Q4	us-gaap	Deferred Tax Liabilities Investment In Noncontrolled Affiliates DeferredTaxLiabilitiesInvestmentInNoncontrolledAffiliates	201000000	USD
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CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15000000	USD
CY2018Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	26000000	USD
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CY2020	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	3000000	USD
CY2019	us-gaap	Unrecognized Tax Benefits Decreases Resulting From Settlements With Taxing Authorities UnrecognizedTaxBenefitsDecreasesResultingFromSettlementsWithTaxingAuthorities	13000000	USD
CY2020Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15000000	USD
CY2019Q4	us-gaap	Unrecognized Tax Benefits UnrecognizedTaxBenefits	15000000	USD
CY2020	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	27000000	USD
CY2019	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	36000000	USD
CY2018	us-gaap	Payments Related To Tax Withholding For Share Based Compensation PaymentsRelatedToTaxWithholdingForShareBasedCompensation	19000000	USD
CY2020	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	27000000	USD
CY2019	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	32000000	USD
CY2018	us-gaap	Allocated Share Based Compensation Expense AllocatedShareBasedCompensationExpense	41000000	USD
CY2020Q4	us-gaap	Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized EmployeeServiceShareBasedCompensationNonvestedAwardsTotalCompensationCostNotYetRecognized	23000000	USD
CY2020	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	9000000	USD
CY2019	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	12000000	USD
CY2018	us-gaap	Employee Service Share Based Compensation Tax Benefit From Compensation Expense EmployeeServiceShareBasedCompensationTaxBenefitFromCompensationExpense	4000000	USD
CY2020	us-gaap	Revenue From Related Parties RevenueFromRelatedParties	52000000	USD
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CY2020Q4	nrg	Nuclear Insurance Per Incident Coverage Limit NuclearInsurancePerIncidentCoverageLimit	13800000000	USD
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Files In Submission

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$NRG
NRG ENERGY, INC. Stock $nrg

2020 Form 10-K Financial Statement

#000101387121000005 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NRG NRG ENERGY, INC. Stock $nrg

2020 Form 10-K Financial Statement

#000101387121000005 Filed on March 01, 2021

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NRG
NRG ENERGY, INC. Stock $nrg