$NRG
NRG ENERGY, INC. Stock $nrg

$nrg Overview Financials Valuation SEC Filings Company Website

2019 Q4 Form 8-K Financial Statement

#000101387120000027 Filed on May 07, 2020

Income Statement

Concept	2019 Q4	2019 Q1	2019
Revenue	$2.195B	$2.165B	$9.821B
YoY Change	10.19%	4.84%	3.62%
Cost Of Revenue	$1.654B	$1.651B	$7.303B
YoY Change	20.03%	19.21%	2.74%
Gross Profit	$541.0M	$514.0M	$2.518B
YoY Change	77.38%	-24.41%	6.24%
Gross Profit Margin	24.65%	23.74%	25.64%
Selling, General & Admin	$212.0M	$194.0M	$760.0M
YoY Change	1.92%	10.23%	-4.88%
% of Gross Profit	39.19%	37.74%	30.18%
Research & Development	$2.000M	$2.000M	$7.000M
YoY Change	0.0%	-60.0%	-36.36%
% of Gross Profit	0.37%	0.39%	0.28%
Depreciation & Amortization	$134.0M	$85.00M	$373.0M
YoY Change	48.89%	-29.17%	-11.4%
% of Gross Profit	24.77%	16.54%	14.81%
Operating Expenses	$326.0M	$196.0M	$767.0M
YoY Change	24.9%	8.29%	-5.31%
Operating Profit	$209.0M	$221.0M	$1.290B
YoY Change	326.53%	-38.78%	31.36%
Interest Expense	-$101.0M	$114.0M	$413.0M
YoY Change	-27.34%	-1.72%	-14.49%
% of Operating Profit	-48.33%	51.58%	32.02%
Other Income/Expense, Net	$17.00M	-$123.0M	-$504.0M
YoY Change	-22.73%	5.13%	-2.14%
Pretax Income	$120.0M	$98.00M	$786.0M
YoY Change	-178.43%	-59.84%	68.31%
Income Tax	-$3.343B	$4.000M	-$3.334B
% Of Pretax Income	-2785.83%	4.08%	-424.17%
Net Earnings	$3.385B	$482.0M	$4.438B
YoY Change	-26138.46%	72.76%	1555.97%
Net Earnings / Revenue	154.21%	22.26%	45.19%
Basic Earnings Per Share	$13.48	$1.73	$16.94
Diluted Earnings Per Share	$13.37	$1.72	$16.81
COMMON SHARES
Basic Shares Outstanding	251.0M shares	278.0M shares	262.0M shares
Diluted Shares Outstanding	253.0M shares	280.0M shares	264.0M shares

Balance Sheet

Concept	2019 Q4	2019 Q1	2019
SHORT-TERM ASSETS
Cash & Short-Term Investments	$345.0M	$859.0M	$345.0M
YoY Change	-38.72%	12.43%	-38.72%
Cash & Equivalents	$345.0M	$859.0M	$345.0M
Short-Term Investments
Other Short-Term Assets	$1.335B	$1.310B	$1.335B
YoY Change	-16.61%	-42.77%	-16.61%
Inventory	$383.0M	$391.0M	$383.0M
Prepaid Expenses
Receivables	$1.025B	$898.0M	$1.025B
Other Receivables	$0.00	$0.00	$0.00
Total Short-Term Assets	$3.088B	$3.458B	$3.088B
YoY Change	-14.22%	-24.12%	-14.22%
LONG-TERM ASSETS
Property, Plant & Equipment	$2.593B	$2.650B	$3.057B
YoY Change	-14.93%	-80.95%	0.3%
Goodwill	$579.0M	$573.0M
YoY Change	1.05%	6.31%
Intangibles
YoY Change
Long-Term Investments	$388.0M	$387.0M	$388.0M
YoY Change	-5.83%	-61.72%	-5.83%
Other Assets	$240.0M	$255.0M	$4.630B
YoY Change	-16.96%	-62.56%	92.6%
Total Long-Term Assets	$9.443B	$3.422B	$9.443B
YoY Change	137.26%	-35.24%	34.36%
TOTAL ASSETS
Total Short-Term Assets	$3.088B	$3.458B	$3.088B
Total Long-Term Assets	$9.443B	$3.422B	$9.443B
Total Assets	$12.53B	$9.530B	$12.53B
YoY Change	17.91%	-59.88%	17.91%
SHORT-TERM LIABILITIES
YoY Change
Accounts Payable	$722.0M	$697.0M	$722.0M
YoY Change	-16.34%	-11.44%	-16.34%
Accrued Expenses	$736.0M	$624.0M	$736.0M
YoY Change	8.24%	-24.18%	8.24%
Deferred Revenue
YoY Change
Short-Term Debt	$0.00	$0.00	$0.00
YoY Change
Long-Term Debt Due	$88.00M	$124.0M	$88.00M
YoY Change	22.22%	-87.03%	22.22%
Total Short-Term Liabilities	$2.359B	$1.945B	$2.359B
YoY Change	-1.63%	-47.55%	-1.63%
LONG-TERM LIABILITIES
Long-Term Debt	$5.803B	$6.366B	$5.803B
YoY Change	-10.02%	-58.68%	-10.02%
Other Long-Term Liabilities	$1.084B	$1.089B	$2.674B
YoY Change	-14.91%	-4.14%	-8.77%
Total Long-Term Liabilities	$8.494B	$9.105B	$8.477B
YoY Change	-10.07%	-48.58%	-9.63%
TOTAL LIABILITIES
Total Short-Term Liabilities	$2.359B	$1.945B	$2.359B
Total Long-Term Liabilities	$8.494B	$9.105B	$8.477B
Total Liabilities	$10.85B	$11.05B	$10.87B
YoY Change	-8.36%	-48.4%	-8.34%
SHAREHOLDERS EQUITY
Retained Earnings	-$1.616B	-$5.548B
YoY Change	-73.17%	-7.26%
Common Stock	$8.505B	$8.477B
YoY Change	-0.11%	1.12%
Preferred Stock
YoY Change
Treasury Stock (at cost)	$5.039B	$4.371B
YoY Change	38.74%	76.68%
Treasury Stock Shares	172.9M shares	154.2M shares
Shareholders Equity	$1.658B	-$1.538B	$1.658B
YoY Change
Total Liabilities & Shareholders Equity	$12.53B	$9.530B	$12.53B
YoY Change	17.91%	-59.88%	17.91%

Cashflow Statement

Concept	2019 Q4	2019 Q1	2019
OPERATING ACTIVITIES
Net Income	$3.385B	$482.0M	$4.438B
YoY Change	-26138.46%	72.76%	1555.97%
Depreciation, Depletion And Amortization	$134.0M	$85.00M	$373.0M
YoY Change	48.89%	-29.17%	-11.4%
Cash From Operating Activities	$516.0M	-$91.00M	$1.413B
YoY Change	159.3%	-126.0%	2.61%
INVESTING ACTIVITIES
Capital Expenditures	-$45.00M	$49.00M	$228.0M
YoY Change	4.65%	-68.39%	-41.24%
Acquisitions		$16.00M	$355.0M
YoY Change		700.0%	46.09%
Other Investing Activities	-$13.00M	$1.000M	-$6.000M
YoY Change	-87.38%		-200.0%
Cash From Investing Activities	-$58.00M	$1.196B	$556.0M
YoY Change	-60.27%	-360.0%	-371.22%
FINANCING ACTIVITIES
Cash Dividend Paid
YoY Change
Common Stock Issuance & Retirement, Net		$2.000M	$1.437B
YoY Change		-71.43%	16.92%
Debt Paid & Issued, Net
YoY Change
Cash From Financing Activities	-350.0M	-$784.0M	-$2.148B
YoY Change	-59.3%	5500.0%	40.76%
NET CHANGE
Cash From Operating Activities	516.0M	-$91.00M	$1.413B
Cash From Investing Activities	-58.00M	$1.196B	$556.0M
Cash From Financing Activities	-350.0M	-$784.0M	-$2.148B
Net Change In Cash	108.0M	$272.0M	-$228.0M
YoY Change	-113.38%	-488.57%	-51.8%
FREE CASH FLOW
Cash From Operating Activities	$516.0M	-$91.00M	$1.413B
Capital Expenditures	-$45.00M	$49.00M	$228.0M
Free Cash Flow	$561.0M	-$140.0M	$1.185B
YoY Change	131.82%	-171.79%	19.82%

Facts In Submission

Frame	Concept Type	Concept / XBRL Key	Value	Unit
CY2020Q2	dei	Entity Central Index Key EntityCentralIndexKey	0001013871
CY2020Q2	dei	Amendment Flag AmendmentFlag	true
CY2019	nrg	Period Beyondwhich Comapny Can Not Predict Holdingof Collateral PeriodBeyondwhichComapnyCanNotPredictHoldingofCollateral	P12M
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation Expected Timing Of Satisfaction Period1 RevenueRemainingPerformanceObligationExpectedTimingOfSatisfactionPeriod1	P1Y
CY2019	nrg	Estimated Counterparty Credit Risk Exposure To Certain Counterparties Period EstimatedCounterpartyCreditRiskExposureToCertainCounterpartiesPeriod	P5Y
CY2019	nrg	Periodofretrospectivepremiumadjustments Periodofretrospectivepremiumadjustments	P24M
CY2020Q2	dei	Document Type DocumentType	8-K
CY2020Q2	dei	Document Period End Date DocumentPeriodEndDate	2020-05-07
CY2020Q2	dei	Entity Registrant Name EntityRegistrantName	NRG ENERGY, INC.
CY2020Q2	dei	Entity Incorporation State Country Code EntityIncorporationStateCountryCode	DE
CY2020Q2	dei	Entity File Number EntityFileNumber	001-15891
CY2020Q2	dei	Entity Tax Identification Number EntityTaxIdentificationNumber	41-1724239
CY2020Q2	dei	Entity Address Address Line1 EntityAddressAddressLine1	804 Carnegie Center
CY2020Q2	dei	Entity Address City Or Town EntityAddressCityOrTown	Princeton
CY2020Q2	dei	Entity Address State Or Province EntityAddressStateOrProvince	NJ
CY2020Q2	dei	Entity Address Postal Zip Code EntityAddressPostalZipCode	08540
CY2020Q2	dei	City Area Code CityAreaCode	609
CY2020Q2	dei	Local Phone Number LocalPhoneNumber	524-4500
CY2020Q2	dei	Written Communications WrittenCommunications	false
CY2020Q2	dei	Soliciting Material SolicitingMaterial	false
CY2020Q2	dei	Pre Commencement Tender Offer PreCommencementTenderOffer	false
CY2020Q2	dei	Pre Commencement Issuer Tender Offer PreCommencementIssuerTenderOffer	false
CY2020Q2	dei	Security12b Title Security12bTitle	Common Stock, par value $0.01
CY2020Q2	dei	Trading Symbol TradingSymbol	NRG
CY2020Q2	dei	Security Exchange Name SecurityExchangeName	NYSE
CY2020Q2	dei	Entity Emerging Growth Company EntityEmergingGrowthCompany	false
CY2019	us-gaap	Revenues Revenues	9821000000	USD
CY2018	us-gaap	Revenues Revenues	9478000000	USD
CY2017	us-gaap	Revenues Revenues	9074000000	USD
CY2019	us-gaap	Cost Of Revenue CostOfRevenue	7303000000	USD
CY2018	us-gaap	Cost Of Revenue CostOfRevenue	7108000000	USD
CY2017	us-gaap	Cost Of Revenue CostOfRevenue	6886000000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	373000000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	421000000	USD
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CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	5000000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	99000000	USD
CY2017	us-gaap	Asset Impairment Charges AssetImpairmentCharges	1534000000	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	827000000	USD
CY2018	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	799000000	USD
CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	836000000	USD
CY2019	us-gaap	Restructuring Costs RestructuringCosts	23000000	USD
CY2018	us-gaap	Restructuring Costs RestructuringCosts	90000000	USD
CY2017	us-gaap	Restructuring Costs RestructuringCosts	44000000	USD
CY2019	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	7000000	USD
CY2018	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	11000000	USD
CY2017	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	22000000	USD
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CY2019	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	0	USD
CY2018	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	0	USD
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CY2019	us-gaap	Operating Income Loss OperatingIncomeLoss	1290000000	USD
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CY2019	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	2000000	USD
CY2018	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	9000000	USD
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CY2019	us-gaap	Impairment Of Investments ImpairmentOfInvestments	108000000	USD
CY2018	us-gaap	Impairment Of Investments ImpairmentOfInvestments	15000000	USD
CY2017	us-gaap	Impairment Of Investments ImpairmentOfInvestments	79000000	USD
CY2019	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	66000000	USD
CY2018	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	18000000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	51000000	USD
CY2019	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-51000000	USD
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CY2019	us-gaap	Interest Expense InterestExpense	413000000	USD
CY2018	us-gaap	Interest Expense InterestExpense	483000000	USD
CY2017	us-gaap	Interest Expense InterestExpense	557000000	USD
CY2019	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-504000000	USD
CY2018	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-515000000	USD
CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-648000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	786000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	467000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-1389000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3334000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-44000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	4120000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	460000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-1345000000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	321000000	USD
CY2018	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-192000000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-992000000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	4441000000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	268000000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	-2337000000	USD
CY2019	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	3000000	USD
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CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	-2153000000	USD
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
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	317000000	shares
CY2019	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	15.71
CY2018	us-gaap	Income Loss From Continuing Operations Per Basic Share IncomeLossFromContinuingOperationsPerBasicShare	1.51
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CY2019	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	1.23
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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
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	317000000	shares
CY2019	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	15.59
CY2018	us-gaap	Income Loss From Continuing Operations Per Diluted Share IncomeLossFromContinuingOperationsPerDilutedShare	1.49
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CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	16.81
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CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	1000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-8000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	78000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	35000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-46000000	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
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	63000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	4343000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	246000000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	-2274000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	3000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	14000000	USD
CY2017	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	-179000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	4340000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	232000000	USD
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CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	345000000	USD
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CY2018Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	33000000	USD
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CY2018Q4	us-gaap	Derivative Instruments And Hedges DerivativeInstrumentsAndHedges	764000000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	190000000	USD
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CY2019Q4	us-gaap	Assets Assets	12531000000	USD
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CY2018Q4	nrg	Liabilities Held For Sale Not Part Of Disposal Group Or Discontinued Operations Non Current LiabilitiesHeldForSaleNotPartOfDisposalGroupOrDiscontinuedOperationsNonCurrent	65000000	USD
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CY2018Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	9445000000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	10853000000	USD
CY2018Q4	us-gaap	Liabilities Liabilities	11843000000	USD
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CY2019Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
CY2018Q4	us-gaap	Commitments And Contingencies CommitmentsAndContingencies		USD
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CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1658000000	USD
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CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	12531000000	USD
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CY2019	us-gaap	Accretion Expense Including Asset Retirement Obligations AccretionExpenseIncludingAssetRetirementObligations	51000000	USD
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CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	95000000	USD
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CY2019	nrg	Amortization Of Nuclear Fuel AmortizationOfNuclearFuel	52000000	USD
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CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	20000000	USD
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CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	35000000	USD
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CY2018	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	49000000	USD
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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
CY2017	us-gaap	Nondebtor Reorganization Items Net Gain Loss On Settlement Of Other Claims1 NondebtorReorganizationItemsNetGainLossOnSettlementOfOtherClaims1	0	USD
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CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	355000000	USD
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CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	416000000	USD
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CY2019	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	USD
CY2018	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	268000000	USD
CY2017	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	0	USD
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CY2017	nrg	Net Contributions To Distributions From Discontinued Operations NetContributionsToDistributionsFromDiscontinuedOperations	150000000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-6000000	USD
CY2018	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	6000000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-30000000	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
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	340000000	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
CY2017	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-979000000	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
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-639000000	USD
CY2019	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	32000000	USD
CY2018	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	37000000	USD
CY2017	us-gaap	Payments Of Dividends Common Stock PaymentsOfDividendsCommonStock	38000000	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
CY2017	us-gaap	Payments For Repurchase Of Common Stock PaymentsForRepurchaseOfCommonStock	0	USD
CY2019	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	26000000	USD
CY2018	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	32000000	USD
CY2017	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	42000000	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
CY2017	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-30000000	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
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	-2000000	USD
CY2019	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	1916000000	USD
CY2018	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	1100000000	USD
CY2017	us-gaap	Proceeds From Other Debt ProceedsFromOtherDebt	1178000000	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	35000000	USD
CY2018	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	19000000	USD
CY2017	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	18000000	USD
CY2019	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	2571000000	USD
CY2018	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1734000000	USD
CY2017	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1884000000	USD
CY2019	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	0	USD
CY2018	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	26000000	USD
CY2017	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	125000000	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
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-2191000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-1997000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-969000000	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
CY2017	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	-169000000	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
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1138000000	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
CY2017	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
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
CY2017	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	-394000000	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
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	226000000	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
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	860000000	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
CY2016Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	4446000000	USD
CY2017	us-gaap	Net Income Loss Including Portion Attributable To Nonredeemable Noncontrolling Interest NetIncomeLossIncludingPortionAttributableToNonredeemableNoncontrollingInterest	-2251000000	USD
CY2017	nrg	Other Comprehensive Income Loss Net Of Tax And Adjustment For New Accounting Standard OtherComprehensiveIncomeLossNetOfTaxAndAdjustmentForNewAccountingStandard	51000000	USD
CY2017	us-gaap	Stock Issued During Period Value Employee Stock Purchase Plan StockIssuedDuringPeriodValueEmployeeStockPurchasePlan	6000000	USD
CY2017	us-gaap	Adjustments To Additional Paid In Capital Sharebased Compensation Requisite Service Period Recognition Value AdjustmentsToAdditionalPaidInCapitalSharebasedCompensationRequisiteServicePeriodRecognitionValue	25000000	USD
CY2017	us-gaap	Stock Issued During Period Value New Issues StockIssuedDuringPeriodValueNewIssues	4000000	USD
CY2017	us-gaap	Dividends Common Stock Cash DividendsCommonStockCash	38000000	USD
CY2017	us-gaap	Minority Interest Decrease From Distributions To Noncontrolling Interest Holders MinorityInterestDecreaseFromDistributionsToNoncontrollingInterestHolders	65000000	USD
CY2017	nrg	Noncontrolling Interest Contributionsfrom Noncontrolling Interest Holders NoncontrollingInterestContributionsfromNoncontrollingInterestHolders	160000000	USD
CY2017	us-gaap	New Accounting Pronouncement Or Change In Accounting Principle Effect Of Adoption Quantification NewAccountingPronouncementOrChangeInAccountingPrincipleEffectOfAdoptionQuantification	-257000000	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
CY2017Q4	us-gaap	Cumulative Effect Of New Accounting Principle In Period Of Adoption CumulativeEffectOfNewAccountingPrincipleInPeriodOfAdoption	15000000	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
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
CY2017	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
CY2019	us-gaap	Nature Of Operations NatureOfOperations	<span style="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:700;line-height:120%;"> </span><div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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 electricity and related products and services in major competitive power markets in the U.S. and Canada in a manner that delivers value to all of NRG's stakeholders. NRG is a customer-driven business focused on perfecting the integrated model by balancing retail load with generation supply within its deregulated markets. The Company sells 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 as of December 31, 2019.</span></div><div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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 currently makes financial decisions and allocates resources. </span></div><div style="text-indent:22.5pt;text-align:justify;margin-bottom:3pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:-13.5pt;padding-left:36pt;text-align:justify;margin-bottom:3pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%;">•</span><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:-13.5pt;padding-left:36pt;text-align:justify;margin-bottom:3pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%;">•</span><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:-13.5pt;padding-left:36pt;text-align:justify;margin-bottom:3pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Arial',sans-serif;font-size:12pt;font-weight:400;line-height:115%;">•</span><span style="background-color:rgb(255,255,255, 0.0);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, the remaining Home Solar assets 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="text-indent:-13.5pt;padding-left:36pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%;">•</span><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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 19, </span><span style="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:115%;">.</span></div><div style="text-indent:22.5pt;margin-top:9pt;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);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><div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">, 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. </span></div><div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);color:#000000;font-family:'Times New Roman',sans-serif;font-size:10pt;font-weight:400;line-height:120%;">On June 14, 2017, or the Petition Date, GenOn, along with GenOn Americas Generation and certain of their directly and indirectly-owned subsidiaries, or collectively the GenOn Entities, filed voluntary petitions for relief under the Chapter 11 Cases, of the U.S. Bankruptcy Code. As a result of the bankruptcy filings and beginning on June 14, 2017, GenOn and its subsidiaries were deconsolidated from NRG's consolidated financial statements. NRG determined that this disposal of GenOn and its subsidiaries was a discontinued operation and, accordingly, the financial information for all historical periods was recast to reflect GenOn as a discontinued operation. GenOn's plan of reorganization was confirmed on December 14, 2018.</span></div>
CY2019Q4	nrg	Power Generation Capacity Megawatts PowerGenerationCapacityMegawatts	23000	MW
CY2019	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	4117000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	465000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations IncomeLossFromContinuingOperations	-977000000	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
CY2017	nrg	Income Loss From Discontinued Operations Including Adjustment For Discontinued Operations Noncontrolling Interest Net Of Tax Attributable To Parent IncomeLossFromDiscontinuedOperationsIncludingAdjustmentForDiscontinuedOperationsNoncontrollingInterestNetOfTaxAttributableToParent	-1176000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	-2153000000	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
CY2017Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	770000000	USD
CY2019Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	32000000	USD
CY2018Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	33000000	USD
CY2017Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	37000000	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
CY2017Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	279000000	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
CY2019Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	43000000	USD
CY2018Q4	us-gaap	Allowance For Doubtful Accounts Receivable Current AllowanceForDoubtfulAccountsReceivableCurrent	32000000	USD
CY2019	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	3000000	USD
CY2018	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	7000000	USD
CY2017	us-gaap	Interest Costs Capitalized InterestCostsCapitalized	20000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1300000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1200000000	USD
CY2019Q4	us-gaap	Lessor Operating Lease Term Of Contract LessorOperatingLeaseTermOfContract	P20Y
CY2019	us-gaap	Operating Leases Income Statement Contingent Revenue OperatingLeasesIncomeStatementContingentRevenue	5000000	USD
CY2018	us-gaap	Operating Leases Income Statement Contingent Revenue OperatingLeasesIncomeStatementContingentRevenue	104000000	USD
CY2017	us-gaap	Operating Leases Income Statement Contingent Revenue OperatingLeasesIncomeStatementContingentRevenue	253000000	USD
CY2019	nrg	Gross Receipts Tax GrossReceiptsTax	109000000	USD
CY2018	nrg	Gross Receipts Tax GrossReceiptsTax	99000000	USD
CY2017	nrg	Gross Receipts Tax GrossReceiptsTax	92000000	USD
CY2019	nrg	Cost Of Services Energy Services Unbilled CostOfServicesEnergyServicesUnbilled	103000000	USD
CY2018	nrg	Cost Of Services Energy Services Unbilled CostOfServicesEnergyServicesUnbilled	105000000	USD
CY2017	nrg	Cost Of Services Energy Services Unbilled CostOfServicesEnergyServicesUnbilled	107000000	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
CY2017Q4	us-gaap	Accumulated Other Comprehensive Income Loss Foreign Currency Translation Adjustment Net Of Tax AccumulatedOtherComprehensiveIncomeLossForeignCurrencyTranslationAdjustmentNetOfTax	-2000000	USD
CY2019	us-gaap	Concentration Risk Credit Risk ConcentrationRiskCreditRisk	<div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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 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="background-color:rgb(255,255,255, 0.0);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="background-color:rgb(255,255,255, 0.0);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></div>
CY2016Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	46000000	USD
CY2017	nrg	Redeemable Noncontrolling Interest Cash Contributionsfrom Noncontrolling Interest Holders RedeemableNoncontrollingInterestCashContributionsfromNoncontrollingInterestHolders	99000000	USD
CY2017	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	-72000000	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
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	20000000	USD
CY2019	us-gaap	Net Income Loss Attributable To Redeemable Noncontrolling Interest NetIncomeLossAttributableToRedeemableNoncontrollingInterest	3000000	USD
CY2019	us-gaap	Advertising Expense AdvertisingExpense	66000000	USD
CY2018	us-gaap	Advertising Expense AdvertisingExpense	73000000	USD
CY2017	us-gaap	Advertising Expense AdvertisingExpense	66000000	USD
CY2019	us-gaap	Restructuring Costs RestructuringCosts	23000000	USD
CY2018	us-gaap	Restructuring Costs RestructuringCosts	90000000	USD
CY2017	us-gaap	Restructuring Costs RestructuringCosts	44000000	USD
CY2018	us-gaap	Revenue From Contract With Customer Excluding Assessed Tax RevenueFromContractWithCustomerExcludingAssessedTax	8148000000	USD
CY2018	us-gaap	Operating Lease Lease Income OperatingLeaseLeaseIncome	21000000	USD
CY2019	us-gaap	Use Of Estimates UseOfEstimates	<div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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>
CY2019	us-gaap	Prior Period Reclassification Adjustment Description PriorPeriodReclassificationAdjustmentDescription	<div style="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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="text-indent:22.5pt;text-align:justify;margin-bottom:6pt;"><span style="background-color:rgb(255,255,255, 0.0);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>
CY2019Q1	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	404000000	USD
CY2019Q1	us-gaap	Operating Lease Liability OperatingLeaseLiability	321000000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	564000000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	604000000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	303000000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	42000000	USD
CY2019Q4	us-gaap	Revenue Remaining Performance Obligation RevenueRemainingPerformanceObligation	8000000	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
CY2019Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	133000000	USD
CY2018Q4	us-gaap	Capitalized Contract Cost Net CapitalizedContractCostNet	111000000	USD
CY2019Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	1025000000	USD
CY2018Q4	us-gaap	Accounts Receivable Net AccountsReceivableNet	1024000000	USD
CY2019Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	402000000	USD
CY2018Q4	us-gaap	Unbilled Contracts Receivable UnbilledContractsReceivable	392000000	USD
CY2019Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	82000000	USD
CY2018Q4	us-gaap	Contract With Customer Liability ContractWithCustomerLiability	67000000	USD
CY2019	nrg	Contractwith Customer Liability Increase For Cash Payments Received ContractwithCustomerLiabilityIncreaseForCashPaymentsReceived	24000000	USD
CY2018	nrg	Contractwith Customer Liability Increase For Cash Payments Received ContractwithCustomerLiabilityIncreaseForCashPaymentsReceived	19000000	USD
CY2019	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	13000000	USD
CY2018	us-gaap	Contract With Customer Liability Revenue Recognized ContractWithCustomerLiabilityRevenueRecognized	16000000	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
CY2018Q4	us-gaap	Available For Sale Securities Debt Securities AvailableForSaleSecuritiesDebtSecurities	39000000	USD
CY2018Q4	us-gaap	Financial Instruments Owned Us Government And Agency Obligations At Fair Value FinancialInstrumentsOwnedUSGovernmentAndAgencyObligationsAtFairValue	1000000	USD
CY2018Q4	us-gaap	Assets Fair Value Disclosure AssetsFairValueDisclosure	1792000000	USD
CY2018Q4	us-gaap	Liabilities Fair Value Disclosure LiabilitiesFairValueDisclosure	977000000	USD
CY2019Q4	nrg	Derivative Asset Fair Value Determined Using Valuation Techniques Percentage DerivativeAssetFairValueDeterminedUsingValuationTechniquesPercentage	0.16
CY2018	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	85000000	USD
CY2019Q4	nrg	Derivative Liability Fair Value Determined Using Valuation Techniques Percentage DerivativeLiabilityFairValueDeterminedUsingValuationTechniquesPercentage	0.14
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	190000000	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	32000000	USD
CY2019Q4	nrg	Amount Of Credit Exposure To Significant Portion Of All Counterparties AmountOfCreditExposureToSignificantPortionOfAllCounterparties	239000000	USD
CY2019Q4	nrg	Collateral Held Cash And Letters Of Credit CollateralHeldCashAndLettersOfCredit	51000000	USD
CY2019Q4	nrg	Net Credit Exposure NetCreditExposure	233000000	USD
CY2019	nrg	Counterparty Credit Risk Exposure Percentage Of Credit Risk Roll Off CounterpartyCreditRiskExposurePercentageOfCreditRiskRollOff	0.67
CY2019Q4	nrg	Credit Derivative Maximum Net Exposure Percentage CreditDerivativeMaximumNetExposurePercentage	1
CY2019Q4	nrg	Credit Derivative Maximum Net Exposure Percentage CreditDerivativeMaximumNetExposurePercentage	1
CY2019Q4	nrg	Number Of Wholesale Counterparties With Credit Risk Exposure NumberOfWholesaleCounterpartiesWithCreditRiskExposure	33000000	counterparty
CY2019	nrg	Counterparty Credit Risk Exposure Percentage Threshold CounterpartyCreditRiskExposurePercentageThreshold	0.10
CY2019	nrg	Estimated Counterparty Credit Risk Exposure To Certain Counterparties EstimatedCounterpartyCreditRiskExposureToCertainCounterparties	548000000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	95000000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	68000000	USD
CY2018Q4	nrg	Fair Valueof Gross Derivative Assets Liabilities Net FairValueofGrossDerivativeAssetsLiabilitiesNet	104000000	USD
CY2018Q4	nrg	Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset DerivativeAssetFairValueGrossLiabilityNetOfDerivativeLiabilityFairValueGrossAsset	0	USD
CY2018Q4	nrg	Derivative Collateral Obligation To Return Cash Net Of Derivative Collateral Right To Reclaim Cash DerivativeCollateralObligationToReturnCashNetOfDerivativeCollateralRightToReclaimCash	83000000	USD
CY2018Q4	nrg	Derivative Asset Fair Value Amount Offset Against Collateral Net Of Derivative Liability Fair Value Amount Offset Against Collateral DerivativeAssetFairValueAmountOffsetAgainstCollateralNetOfDerivativeLiabilityFairValueAmountOffsetAgainstCollateral	187000000	USD
CY2018	nrg	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Divestiture Of Business Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIDivestitureOfBusinessNetOfTax	25000000	USD
CY2017	nrg	Other Comprehensive Income Loss Reclassification Adjustment From Aoci Divestiture Of Business Net Of Tax OtherComprehensiveIncomeLossReclassificationAdjustmentFromAOCIDivestitureOfBusinessNetOfTax	0	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
CY2017	nrg	Reversal Previously Recognized Unrealized Gains Losses Settled Positions Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesSettledPositionsEconomicHedges	-47000000	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
CY2017	nrg	Reversal Previously Recognized Unrealized Gains Losses Acquiredas Partof Acquisition Economic Hedges ReversalPreviouslyRecognizedUnrealizedGainsLossesAcquiredasPartofAcquisitionEconomicHedges	0	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
CY2017	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	159000000	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
CY2017	nrg	Unrealized Gain Loss On Derivatives Mark To Market Economic Hedging Activities UnrealizedGainLossOnDerivativesMarkToMarketEconomicHedgingActivities	206000000	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
CY2017	nrg	Reversal Previously Unrecognized Unrealized Gains Losses Settled Positions Trading Activity ReversalPreviouslyUnrecognizedUnrealizedGainsLossesSettledPositionsTradingActivity	25000000	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
CY2017	nrg	Derivative Unrealized Gains On Open Positions Related To Trading Activity Net DerivativeUnrealizedGainsOnOpenPositionsRelatedToTradingActivityNet	14000000	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
CY2017	nrg	Unrealized Gain Losson Derivatives Mark To Market Trading Activities UnrealizedGainLossonDerivativesMarkToMarketTradingActivities	-11000000	USD
CY2019	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	0	USD
CY2018	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	31000000	USD
CY2017	us-gaap	Unrealized Gain Loss On Derivatives UnrealizedGainLossOnDerivatives	195000000	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
CY2017	us-gaap	Derivative Instruments Not Designated As Hedging Instruments Gain Loss Net DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsGainLossNet	159000000	USD
CY2019Q4	us-gaap	Derivative Net Liability Position Aggregate Fair Value DerivativeNetLiabilityPositionAggregateFairValue	3000000	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
CY2018Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	663000000	USD
CY2018	nrg	Decommissioning Fund Investments Unrealized Gains DecommissioningFundInvestmentsUnrealizedGains	234000000	USD
CY2018	nrg	Decommissioning Fund Investments Unrealized Loss DecommissioningFundInvestmentsUnrealizedLoss	6000000	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
CY2017	us-gaap	Debt Securities Available For Sale Realized Gain DebtSecuritiesAvailableForSaleRealizedGain	22000000	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
CY2017	us-gaap	Debt Securities Available For Sale Realized Loss DebtSecuritiesAvailableForSaleRealizedLoss	8000000	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
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	501000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Petroleum EnergyRelatedInventoryPetroleum	73000000	USD
CY2018Q4	us-gaap	Energy Related Inventory Petroleum EnergyRelatedInventoryPetroleum	74000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	93000000	USD
CY2018Q4	us-gaap	Energy Related Inventory Coal EnergyRelatedInventoryCoal	97000000	USD
CY2019Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	21000000	USD
CY2018Q4	us-gaap	Energy Related Inventory Natural Gas In Storage EnergyRelatedInventoryNaturalGasInStorage	28000000	USD
CY2019Q4	us-gaap	Other Inventories Spare Parts OtherInventoriesSpareParts	196000000	USD
CY2018Q4	us-gaap	Other Inventories Spare Parts OtherInventoriesSpareParts	213000000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	383000000	USD
CY2018Q4	us-gaap	Inventory Net InventoryNet	412000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	4345000000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Plant In Service PublicUtilitiesPropertyPlantAndEquipmentPlantInService	4859000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1752000000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Accumulated Depreciation PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation	1811000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	2593000000	USD
CY2018Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	3048000000	USD
CY2019	us-gaap	Operating Lease Cost OperatingLeaseCost	109000000	USD
CY2019	us-gaap	Short Term Lease Cost ShortTermLeaseCost	3000000	USD
CY2019	us-gaap	Variable Lease Cost VariableLeaseCost	6000000	USD
CY2019	us-gaap	Sublease Income SubleaseIncome	17000000	USD
CY2019	us-gaap	Lease Cost LeaseCost	101000000	USD
CY2019	us-gaap	Operating Lease Payments OperatingLeasePayments	104000000	USD
CY2019	us-gaap	Right Of Use Asset Obtained In Exchange For Operating Lease Liability RightOfUseAssetObtainedInExchangeForOperatingLeaseLiability	215000000	USD
CY2019Q4	us-gaap	Operating Lease Weighted Average Remaining Lease Term1 OperatingLeaseWeightedAverageRemainingLeaseTerm1	P7Y9M18D
CY2019Q4	us-gaap	Operating Lease Weighted Average Discount Rate Percent OperatingLeaseWeightedAverageDiscountRatePercent	0.0572
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Remainder Of Fiscal Year LesseeOperatingLeaseLiabilityPaymentsRemainderOfFiscalYear	96000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Two LesseeOperatingLeaseLiabilityPaymentsDueYearTwo	87000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Three LesseeOperatingLeaseLiabilityPaymentsDueYearThree	87000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Four LesseeOperatingLeaseLiabilityPaymentsDueYearFour	85000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due Year Five LesseeOperatingLeaseLiabilityPaymentsDueYearFive	75000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due After Year Five LesseeOperatingLeaseLiabilityPaymentsDueAfterYearFive	296000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Payments Due LesseeOperatingLeaseLiabilityPaymentsDue	726000000	USD
CY2019Q4	us-gaap	Lessee Operating Lease Liability Undiscounted Excess Amount LesseeOperatingLeaseLiabilityUndiscountedExcessAmount	170000000	USD
CY2019Q4	us-gaap	Operating Lease Liability OperatingLeaseLiability	556000000	USD
CY2018Q4	us-gaap	Operating Leases Future Minimum Payments Due Future Minimum Sublease Rentals OperatingLeasesFutureMinimumPaymentsDueFutureMinimumSubleaseRentals	29000000	USD
CY2019	us-gaap	Other Asset Impairment Charges OtherAssetImpairmentCharges	12000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	579000000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	573000000	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 FiniteLivedIntangibleAssetsUsage	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
CY2017Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	2080000000	USD
CY2018	nrg	Finite Lived Intangible Assets Purchases FiniteLivedIntangibleAssetsPurchases	61000000	USD
CY2018	us-gaap	Finitelived Intangible Assets Acquired1 FinitelivedIntangibleAssetsAcquired1	178000000	USD
CY2018	nrg	Finite Lived Intangible Assets Usage FiniteLivedIntangibleAssetsUsage	27000000	USD
CY2018	nrg	Finite Lived Intangible Assets Write Off Of Fully Amortized Intangible Assets FiniteLivedIntangibleAssetsWriteOffOfFullyAmortizedIntangibleAssets	528000000	USD
CY2018	us-gaap	Impairment Of Intangible Assets Finitelived ImpairmentOfIntangibleAssetsFinitelived	6000000	USD
CY2018	nrg	Finite Lived Intangible Assets Other Changes FiniteLivedIntangibleAssetsOtherChanges	-16000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Gross FiniteLivedIntangibleAssetsGross	1742000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Accumulated Amortization FiniteLivedIntangibleAssetsAccumulatedAmortization	1151000000	USD
CY2018Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	591000000	USD
CY2019	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	151000000	USD
CY2018	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	133000000	USD
CY2017	us-gaap	Amortization Of Intangible Assets AmortizationOfIntangibleAssets	166000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Next Twelve Months FiniteLivedIntangibleAssetsAmortizationExpenseNextTwelveMonths	189000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Two FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo	141000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Three FiniteLivedIntangibleAssetsAmortizationExpenseYearThree	127000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Four FiniteLivedIntangibleAssetsAmortizationExpenseYearFour	128000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Amortization Expense Year Five FiniteLivedIntangibleAssetsAmortizationExpenseYearFive	93000000	USD
CY2019Q4	nrg	Other Assets Noncurrent Emission Allowances OtherAssetsNoncurrentEmissionAllowances	6000000	USD
CY2018Q4	nrg	Other Assets Noncurrent Emission Allowances OtherAssetsNoncurrentEmissionAllowances	12000000	USD
CY2019Q4	us-gaap	Long Term Debt LongTermDebt	6042000000	USD
CY2018Q4	us-gaap	Long Term Debt LongTermDebt	6691000000	USD
CY2018Q4	us-gaap	Capital Lease Obligations CapitalLeaseObligations	1000000	USD
CY2019Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	6042000000	USD
CY2018Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	6692000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	88000000	USD
CY2018Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	72000000	USD
CY2019Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	65000000	USD
CY2018Q4	us-gaap	Deferred Finance Costs Net DeferredFinanceCostsNet	70000000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	86000000	USD
CY2018Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	101000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	5803000000	USD
CY2018Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	6449000000	USD
CY2019Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	86000000	USD
CY2018Q4	us-gaap	Debt Instrument Unamortized Discount Premium Net DebtInstrumentUnamortizedDiscountPremiumNet	101000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Next Twelve Months LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths	88000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Two LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo	6000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Three LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree	5000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Four LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour	4000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal In Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive	604000000	USD
CY2019Q4	us-gaap	Long Term Debt Maturities Repayments Of Principal After Year Five LongTermDebtMaturitiesRepaymentsOfPrincipalAfterYearFive	5335000000	USD
CY2019Q4	us-gaap	Debt And Capital Lease Obligations DebtAndCapitalLeaseObligations	6042000000	USD
CY2018Q2	us-gaap	Deferred Finance Costs Gross DeferredFinanceCostsGross	12000000	USD
CY2019Q2	nrg	Increase Decrease In Long Term Debt IncreaseDecreaseInLongTermDebt	-594000000	USD
CY2018Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	679000000	USD
CY2019	us-gaap	Asset Retirement Obligation Revision Of Estimate AssetRetirementObligationRevisionOfEstimate	27000000	USD
CY2019	us-gaap	Costs Incurred Asset Retirement Obligation Incurred CostsIncurredAssetRetirementObligationIncurred	9000000	USD
CY2019	us-gaap	Asset Retirement Obligation Liabilities Settled AssetRetirementObligationLiabilitiesSettled	33000000	USD
CY2019	us-gaap	Asset Retirement Obligation Accretion Expense AssetRetirementObligationAccretionExpense	46000000	USD
CY2019Q4	us-gaap	Asset Retirement Obligation AssetRetirementObligation	728000000	USD
CY2019Q4	nrg	Number Of Defined Benefit Plans NumberOfDefinedBenefitPlans	2	numberOfBenefitPlans
CY2019	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Increase On Accumulated Postretirement Benefit Obligation DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation	7000000	USD
CY2019	us-gaap	Defined Benefit Plan Effect Of One Percentage Point Decrease On Accumulated Postretirement Benefit Obligation1 DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1	5000000	USD
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
CY2018Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2019	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	22000000	USD
CY2018	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	28000000	USD
CY2017	us-gaap	Defined Contribution Plan Cost Recognized DefinedContributionPlanCostRecognized	56000000	USD
CY2016Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2019Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2017Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2018Q4	us-gaap	Temporary Equity Shares Authorized TemporaryEquitySharesAuthorized	10000000	shares
CY2016Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2017Q4	us-gaap	Common Stock Shares Authorized CommonStockSharesAuthorized	500000000	shares
CY2019Q4	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
CY2017	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
CY2019	nrg	Common Stock Quarterly Dividends Per Share Cash Paid CommonStockQuarterlyDividendsPerShareCashPaid	0.03
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
CY2017	us-gaap	Common Stock Dividends Per Share Cash Paid CommonStockDividendsPerShareCashPaid	0.12
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	nrg	Employee Stock Purchase Plan Exercise Price As Percentage Of Fair Value EmployeeStockPurchasePlanExercisePriceAsPercentageOfFairValue	0.95
CY2019	nrg	Employee Stock Purchase Plan Maximum Percentage Of Compensation Eligible EmployeeStockPurchasePlanMaximumPercentageOfCompensationEligible	0.10
CY2019	nrg	Employee Stock Purchase Plan Exercise Price As Percentage Of Fair Value EmployeeStockPurchasePlanExercisePriceAsPercentageOfFairValue	0.85
CY2019	nrg	Employee Stock Purchase Plan Exercise Price As Percentage Of Fair Value EmployeeStockPurchasePlanExercisePriceAsPercentageOfFairValue	0.85
CY2019Q4	nrg	Common Stock Capital Shares Reserved For Employee Stock Purchase Plan CommonStockCapitalSharesReservedForEmployeeStockPurchasePlan	2885060	shares
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	us-gaap	Equity Method Investments EquityMethodInvestments	388000000	USD
CY2019Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	42000000	USD
CY2018Q4	us-gaap	Retained Earnings Undistributed Earnings From Equity Method Investees RetainedEarningsUndistributedEarningsFromEquityMethodInvestees	34000000	USD
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	-2153000000	USD
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
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	317000000	shares
CY2019	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	16.94
CY2018	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.88
CY2017	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-6.79
CY2019	us-gaap	Net Income Loss NetIncomeLoss	4438000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	-2153000000	USD
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
CY2017	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	317000000	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
CY2017	us-gaap	Incremental Common Shares Attributable To Share Based Payment Arrangements IncrementalCommonSharesAttributableToShareBasedPaymentArrangements	0	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
CY2017	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	317000000	shares
CY2019	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	16.81
CY2018	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.87
CY2017	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-6.79
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	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
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
CY2018Q4	us-gaap	Equity Method Investments EquityMethodInvestments	412000000	USD
CY2018Q4	nrg	Capital Expenditures CapitalExpenditures	388000000	USD
CY2018Q4	us-gaap	Goodwill Goodwill	573000000	USD
CY2018Q4	us-gaap	Assets Assets	10628000000	USD
CY2017	us-gaap	Revenues Revenues	9074000000	USD
CY2017	nrg	Costofrevenueincludingsellingmarketingandgeneraladministrative Costofrevenueincludingsellingmarketingandgeneraladministrative	7766000000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	596000000	USD
CY2017	us-gaap	Asset Impairment Charges AssetImpairmentCharges	1534000000	USD
CY2017	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	22000000	USD
CY2017	us-gaap	Costs And Expenses CostsAndExpenses	9918000000	USD
CY2017	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	87000000	USD
CY2017	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	16000000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	-741000000	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-14000000	USD
CY2017	us-gaap	Impairment Of Investments ImpairmentOfInvestments	79000000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	51000000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-49000000	USD
CY2017	us-gaap	Interest Expense InterestExpense	557000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-1389000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-44000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-1345000000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-992000000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	-2337000000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-184000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	-2153000000	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
CY2017	us-gaap	Current State And Local Tax Expense Benefit CurrentStateAndLocalTaxExpenseBenefit	19000000	USD
CY2019	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	4000000	USD
CY2018	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	0	USD
CY2017	us-gaap	Current Foreign Tax Expense Benefit CurrentForeignTaxExpenseBenefit	0	USD
CY2019	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6000000	USD
CY2018	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	6000000	USD
CY2017	us-gaap	Current Income Tax Expense Benefit CurrentIncomeTaxExpenseBenefit	19000000	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
CY2017	us-gaap	Deferred Federal Income Tax Expense Benefit DeferredFederalIncomeTaxExpenseBenefit	-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
CY2017	us-gaap	Deferred State And Local Income Tax Expense Benefit DeferredStateAndLocalIncomeTaxExpenseBenefit	-5000000	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
CY2017	us-gaap	Deferred Foreign Income Tax Expense Benefit DeferredForeignIncomeTaxExpenseBenefit	2000000	USD
CY2019	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-3340000000	USD
CY2018	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	1000000	USD
CY2017	us-gaap	Deferred Income Tax Expense Benefit DeferredIncomeTaxExpenseBenefit	-63000000	USD
CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3334000000	USD
CY2018	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	7000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-44000000	USD
CY2019	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	-4.242
CY2018	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.015
CY2017	us-gaap	Effective Income Tax Rate Continuing Operations EffectiveIncomeTaxRateContinuingOperations	0.032
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
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
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Domestic IncomeLossFromContinuingOperationsBeforeIncomeTaxesDomestic	-1406000000	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
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Foreign IncomeLossFromContinuingOperationsBeforeIncomeTaxesForeign	17000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	786000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	467000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-1389000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	786000000	USD
CY2018	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	467000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-1389000000	USD
CY2019	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	165000000	USD
CY2018	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	98000000	USD
CY2017	us-gaap	Income Tax Reconciliation Income Tax Expense Benefit At Federal Statutory Income Tax Rate IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate	-486000000	USD
CY2019	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	13000000	USD
CY2018	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	18000000	USD
CY2017	us-gaap	Income Tax Reconciliation State And Local Income Taxes IncomeTaxReconciliationStateAndLocalIncomeTaxes	19000000	USD
CY2019	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	0	USD
CY2018	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	0	USD
CY2017	us-gaap	Income Tax Reconciliation Foreign Income Tax Rate Differential IncomeTaxReconciliationForeignIncomeTaxRateDifferential	2000000	USD
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CY2017	nrg	Tax Cuts And Jobs Act Of2017 Incomplete Accounting Change In Tax Rate Effective Income Tax Rate Reconciliation TaxCutsAndJobsActOf2017IncompleteAccountingChangeInTaxRateEffectiveIncomeTaxRateReconciliation	665000000	USD
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CY2019	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-3334000000	USD
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CY2019Q4	nrg	Nuclear Insurance Per Incident Coverage Limit NuclearInsurancePerIncidentCoverageLimit	13900000000	USD
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CY2019Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	13.48
CY2019Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.46
CY2019Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.76
CY2019Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	1.73
CY2019Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	253000000	shares
CY2019Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	256000000	shares
CY2019Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	267000000	shares
CY2019Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	280000000	shares
CY2019Q4	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.31
CY2019Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.01
CY2019Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.05
CY2019Q1	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	1.38
CY2019Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	13.37
CY2019Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.45
CY2019Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.75
CY2019Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	1.72
CY2018Q4	us-gaap	Revenues Revenues	1992000000	USD
CY2018Q3	us-gaap	Revenues Revenues	2960000000	USD
CY2018Q2	us-gaap	Revenues Revenues	2461000000	USD
CY2018Q1	us-gaap	Revenues Revenues	2065000000	USD
CY2018Q4	us-gaap	Operating Income Loss OperatingIncomeLoss	49000000	USD
CY2018Q3	us-gaap	Operating Income Loss OperatingIncomeLoss	398000000	USD
CY2018Q2	us-gaap	Operating Income Loss OperatingIncomeLoss	174000000	USD
CY2018Q1	us-gaap	Operating Income Loss OperatingIncomeLoss	361000000	USD
CY2018Q4	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-93000000	USD
CY2018Q3	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	287000000	USD
CY2018Q2	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	27000000	USD
CY2018Q1	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	238000000	USD
CY2018Q4	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	80000000	USD
CY2018Q3	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-336000000	USD
CY2018Q2	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	69000000	USD
CY2018Q1	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-5000000	USD
CY2018Q4	us-gaap	Profit Loss ProfitLoss	-13000000	USD
CY2018Q3	us-gaap	Profit Loss ProfitLoss	-49000000	USD
CY2018Q2	us-gaap	Profit Loss ProfitLoss	96000000	USD
CY2018Q1	us-gaap	Profit Loss ProfitLoss	233000000	USD
CY2018Q4	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-2000000	USD
CY2018Q3	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	23000000	USD
CY2018Q2	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	24000000	USD
CY2018Q1	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-46000000	USD
CY2018Q4	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-11000000	USD
CY2018Q3	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	-72000000	USD
CY2018Q2	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	72000000	USD
CY2018Q1	us-gaap	Net Income Loss Available To Common Stockholders Basic NetIncomeLossAvailableToCommonStockholdersBasic	279000000	USD
CY2018Q4	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	289000000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	299000000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	310000000	shares
CY2018Q1	us-gaap	Weighted Average Number Of Shares Outstanding Basic WeightedAverageNumberOfSharesOutstandingBasic	318000000	shares
CY2018Q4	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.28
CY2018Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-1.12
CY2018Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	0.22
CY2018Q1	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Basic Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerBasicShare	-0.02
CY2018Q4	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.04
CY2018Q3	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	-0.24
CY2018Q2	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.23
CY2018Q1	us-gaap	Earnings Per Share Basic EarningsPerShareBasic	0.88
CY2018Q4	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	289000000	shares
CY2018Q3	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	299000000	shares
CY2018Q2	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	314000000	shares
CY2018Q1	us-gaap	Weighted Average Number Of Diluted Shares Outstanding WeightedAverageNumberOfDilutedSharesOutstanding	322000000	shares
CY2018Q4	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.28
CY2018Q3	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-1.12
CY2018Q2	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	0.22
CY2018Q1	us-gaap	Discontinued Operation Income Loss From Discontinued Operation Net Of Tax Per Diluted Share DiscontinuedOperationIncomeLossFromDiscontinuedOperationNetOfTaxPerDilutedShare	-0.02
CY2018Q4	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.04
CY2018Q3	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	-0.24
CY2018Q2	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.23
CY2018Q1	us-gaap	Earnings Per Share Diluted EarningsPerShareDiluted	0.87
CY2019	us-gaap	Revenues Revenues	9821000000	USD
CY2019	us-gaap	Cost Of Revenue CostOfRevenue	7303000000	USD
CY2019	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	373000000	USD
CY2019	us-gaap	Asset Impairment Charges AssetImpairmentCharges	5000000	USD
CY2019	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	827000000	USD
CY2019	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	23000000	USD
CY2019	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	7000000	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
CY2019	nrg	Equity In Earnings Of Consolidated Subsidiaries EquityInEarningsOfConsolidatedSubsidiaries	0	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	Nonoperating Income Expense NonoperatingIncomeExpense	-504000000	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
CY2019	us-gaap	Profit Loss ProfitLoss	4441000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-1000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-19000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	78000000	USD
CY2019	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-98000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	4343000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	3000000	USD
CY2019	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	4340000000	USD
CY2019Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	345000000	USD
CY2019Q4	nrg	Funds Deposited By Counterparties FundsDepositedByCounterparties	32000000	USD
CY2019Q4	us-gaap	Restricted Cash And Cash Equivalents At Carrying Value RestrictedCashAndCashEquivalentsAtCarryingValue	8000000	USD
CY2019Q4	us-gaap	Accounts Receivable Net Current AccountsReceivableNetCurrent	1025000000	USD
CY2019Q4	us-gaap	Inventory Net InventoryNet	383000000	USD
CY2019Q4	us-gaap	Derivative Instruments And Hedges DerivativeInstrumentsAndHedges	860000000	USD
CY2019Q4	us-gaap	Derivative Collateral Right To Reclaim Cash DerivativeCollateralRightToReclaimCash	190000000	USD
CY2019Q4	us-gaap	Prepaid Expense And Other Assets Current PrepaidExpenseAndOtherAssetsCurrent	245000000	USD
CY2019Q4	us-gaap	Assets Current AssetsCurrent	3088000000	USD
CY2019Q4	us-gaap	Public Utilities Property Plant And Equipment Net PublicUtilitiesPropertyPlantAndEquipmentNet	2593000000	USD
CY2019Q4	us-gaap	Investments In Affiliates Subsidiaries Associates And Joint Ventures InvestmentsInAffiliatesSubsidiariesAssociatesAndJointVentures	0	USD
CY2019Q4	us-gaap	Equity Method Investments EquityMethodInvestments	388000000	USD
CY2019Q4	us-gaap	Operating Lease Right Of Use Asset OperatingLeaseRightOfUseAsset	464000000	USD
CY2019Q4	us-gaap	Goodwill Goodwill	579000000	USD
CY2019Q4	us-gaap	Finite Lived Intangible Assets Net FiniteLivedIntangibleAssetsNet	789000000	USD
CY2019Q4	us-gaap	Decommissioning Trust Assets Amount DecommissioningTrustAssetsAmount	794000000	USD
CY2019Q4	us-gaap	Derivative Instruments And Hedges Noncurrent DerivativeInstrumentsAndHedgesNoncurrent	310000000	USD
CY2019Q4	us-gaap	Deferred Income Tax Assets Net DeferredIncomeTaxAssetsNet	3286000000	USD
CY2019Q4	us-gaap	Other Assets Noncurrent OtherAssetsNoncurrent	240000000	USD
CY2019Q4	us-gaap	Regulated Entity Other Assets Noncurrent RegulatedEntityOtherAssetsNoncurrent	6850000000	USD
CY2019Q4	us-gaap	Assets Assets	12531000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations Current LongTermDebtAndCapitalLeaseObligationsCurrent	88000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Current OperatingLeaseLiabilityCurrent	73000000	USD
CY2019Q4	us-gaap	Accounts Payable Current AccountsPayableCurrent	722000000	USD
CY2019Q4	us-gaap	Derivative Liabilities Current DerivativeLiabilitiesCurrent	781000000	USD
CY2019Q4	us-gaap	Derivative Collateral Obligation To Return Cash DerivativeCollateralObligationToReturnCash	32000000	USD
CY2019Q4	us-gaap	Other Accrued Liabilities Current OtherAccruedLiabilitiesCurrent	663000000	USD
CY2019Q4	us-gaap	Liabilities Current LiabilitiesCurrent	2359000000	USD
CY2019Q4	us-gaap	Long Term Debt And Capital Lease Obligations LongTermDebtAndCapitalLeaseObligations	5803000000	USD
CY2019	us-gaap	Payments To Acquire Property Plant And Equipment PaymentsToAcquirePropertyPlantAndEquipment	228000000	USD
CY2019	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	373000000	USD
CY2019	us-gaap	Accretion Expense Including Asset Retirement Obligations AccretionExpenseIncludingAssetRetirementObligations	51000000	USD
CY2019	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	95000000	USD
CY2019Q4	us-gaap	Operating Lease Liability Noncurrent OperatingLeaseLiabilityNoncurrent	483000000	USD
CY2019Q4	us-gaap	Decommissioning Liability Noncurrent DecommissioningLiabilityNoncurrent	298000000	USD
CY2019Q4	nrg	Nuclear Decommissioning Trust Fund Liability Noncurrent NuclearDecommissioningTrustFundLiabilityNoncurrent	487000000	USD
CY2019Q4	us-gaap	Derivative Liabilities Noncurrent DerivativeLiabilitiesNoncurrent	322000000	USD
CY2019Q4	us-gaap	Deferred Income Tax Liabilities Net DeferredIncomeTaxLiabilitiesNet	17000000	USD
CY2019Q4	us-gaap	Other Liabilities Noncurrent OtherLiabilitiesNoncurrent	1084000000	USD
CY2019Q4	us-gaap	Liabilities Noncurrent LiabilitiesNoncurrent	8494000000	USD
CY2019Q4	us-gaap	Liabilities Liabilities	10853000000	USD
CY2019Q4	us-gaap	Redeemable Noncontrolling Interest Equity Other Carrying Amount RedeemableNoncontrollingInterestEquityOtherCarryingAmount	20000000	USD
CY2019Q4	us-gaap	Stockholders Equity Including Portion Attributable To Noncontrolling Interest StockholdersEquityIncludingPortionAttributableToNoncontrollingInterest	1658000000	USD
CY2019Q4	us-gaap	Liabilities And Stockholders Equity LiabilitiesAndStockholdersEquity	12531000000	USD
CY2019	us-gaap	Profit Loss ProfitLoss	4441000000	USD
CY2019	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	321000000	USD
CY2019	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	4120000000	USD
CY2019	nrg	Income Lossfrom Equity Method Investmentof Unconsolidated Affiliates IncomeLossfromEquityMethodInvestmentofUnconsolidatedAffiliates	-14000000	USD
CY2019	us-gaap	Amortization Of Power Contracts Emission Credits AmortizationOfPowerContractsEmissionCredits	52000000	USD
CY2019	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	26000000	USD
CY2019	nrg	Gains Losses On Extinguishment Of Debt Non Cash Portion GainsLossesOnExtinguishmentOfDebtNonCashPortion	-51000000	USD
CY2019	nrg	Amortization Of Intangibles And Out Of Market Contracts AmortizationOfIntangiblesAndOutOfMarketContracts	38000000	USD
CY2019	us-gaap	Share Based Compensation ShareBasedCompensation	20000000	USD
CY2019	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	23000000	USD
CY2019	nrg	Impairment Losses ImpairmentLosses	113000000	USD
CY2019	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	-34000000	USD
CY2019	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	-3353000000	USD
CY2019	nrg	Changes In Collateral Deposits Supporting Energy Risk Management Activities ChangesInCollateralDepositsSupportingEnergyRiskManagementActivities	105000000	USD
CY2019	nrg	Changes In Nuclear Decommissioning Trust Liability ChangesInNuclearDecommissioningTrustLiability	37000000	USD
CY2019	us-gaap	Increase Decrease In Operating Capital IncreaseDecreaseInOperatingCapital	348000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	1405000000	USD
CY2019	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	8000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1413000000	USD
CY2019	nrg	Intercompany Dividend Proceeds Investing IntercompanyDividendProceedsInvesting	0	USD
CY2019	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	355000000	USD
CY2019	us-gaap	Proceeds From Sale Of Intangible Assets ProceedsFromSaleOfIntangibleAssets	11000000	USD
CY2019	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	416000000	USD
CY2019	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	381000000	USD
CY2019	us-gaap	Proceeds From Sale Of Other Productive Assets ProceedsFromSaleOfOtherProductiveAssets	1294000000	USD
CY2019	nrg	Investments In Proceeds From Sales Of Unconsolidated Affiliates InvestmentsInProceedsFromSalesOfUnconsolidatedAffiliates	-91000000	USD
CY2019	nrg	Net Contributions To Distributions From Discontinued Operations NetContributionsToDistributionsFromDiscontinuedOperations	-44000000	USD
CY2019	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-6000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	558000000	USD
CY2019	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-2000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	556000000	USD
CY2019	nrg	Intercompany Dividend Proceeds Financing IntercompanyDividendProceedsFinancing	0	USD
CY2019	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	32000000	USD
CY2019	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	1440000000	USD
CY2019	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	26000000	USD
CY2019	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-2000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	3000000	USD
CY2019	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1916000000	USD
CY2019	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	35000000	USD
CY2019	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	2571000000	USD
CY2019	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-4000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-2191000000	USD
CY2019	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	43000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-2148000000	USD
CY2019	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	49000000	USD
CY2019	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-228000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	613000000	USD
CY2019Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	385000000	USD
CY2018	us-gaap	Revenues Revenues	9478000000	USD
CY2018	us-gaap	Cost Of Revenue CostOfRevenue	7108000000	USD
CY2018	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	421000000	USD
CY2018	us-gaap	Asset Impairment Charges AssetImpairmentCharges	99000000	USD
CY2018	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	799000000	USD
CY2018	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	90000000	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	nrg	Equity In Earnings Of Consolidated Subsidiaries EquityInEarningsOfConsolidatedSubsidiaries	0	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	Nonoperating Income Expense NonoperatingIncomeExpense	-515000000	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
CY2018Q4	us-gaap	Regulated Entity Other Assets Noncurrent RegulatedEntityOtherAssetsNoncurrent	3980000000	USD
CY2018	us-gaap	Net Income Loss NetIncomeLoss	268000000	USD
CY2018	us-gaap	Profit Loss ProfitLoss	268000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Cash Flow Hedge Gain Loss Before Reclassification After Tax OtherComprehensiveIncomeLossCashFlowHedgeGainLossBeforeReclassificationAfterTax	23000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	-11000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	1000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	35000000	USD
CY2018	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	-22000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Including Portion Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxIncludingPortionAttributableToNoncontrollingInterest	246000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax Attributable To Noncontrolling Interest ComprehensiveIncomeNetOfTaxAttributableToNoncontrollingInterest	14000000	USD
CY2018	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	232000000	USD
CY2018Q4	us-gaap	Cash And Cash Equivalents At Carrying Value CashAndCashEquivalentsAtCarryingValue	563000000	USD
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CY2018	nrg	Changes In Nuclear Decommissioning Trust Liability ChangesInNuclearDecommissioningTrustLiability	60000000	USD
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CY2018	us-gaap	Cash Divested From Deconsolidation CashDivestedFromDeconsolidation	268000000	USD
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CY2018	us-gaap	Payments For Repurchase Of Preferred Stock And Preference Stock PaymentsForRepurchaseOfPreferredStockAndPreferenceStock	1250000000	USD
CY2018	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	32000000	USD
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CY2018	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	21000000	USD
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CY2018	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1734000000	USD
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CY2018	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-1997000000	USD
CY2018	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	471000000	USD
CY2018	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1526000000	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
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CY2018	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	-473000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1086000000	USD
CY2018Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	613000000	USD
CY2017	us-gaap	Revenues Revenues	9074000000	USD
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CY2017	nrg	Changes In Nuclear Decommissioning Trust Liability ChangesInNuclearDecommissioningTrustLiability	11000000	USD
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CY2017	us-gaap	Cost Of Revenue CostOfRevenue	6886000000	USD
CY2017	us-gaap	Depreciation Depletion And Amortization DepreciationDepletionAndAmortization	596000000	USD
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CY2017	us-gaap	Selling General And Administrative Expense SellingGeneralAndAdministrativeExpense	836000000	USD
CY2017	us-gaap	Business Combination Acquisition Related Costs BusinessCombinationAcquisitionRelatedCosts	44000000	USD
CY2017	us-gaap	Research And Development Expense ResearchAndDevelopmentExpense	22000000	USD
CY2017	us-gaap	Costs And Expenses CostsAndExpenses	9918000000	USD
CY2017	us-gaap	Related Party Transaction Other Revenues From Transactions With Related Party RelatedPartyTransactionOtherRevenuesFromTransactionsWithRelatedParty	87000000	USD
CY2017	us-gaap	Gain Loss On Sale Of Other Assets GainLossOnSaleOfOtherAssets	16000000	USD
CY2017	us-gaap	Operating Income Loss OperatingIncomeLoss	-741000000	USD
CY2017	nrg	Equity In Earnings Of Consolidated Subsidiaries EquityInEarningsOfConsolidatedSubsidiaries	0	USD
CY2017	us-gaap	Income Loss From Equity Method Investments IncomeLossFromEquityMethodInvestments	-14000000	USD
CY2017	us-gaap	Impairment Of Investments ImpairmentOfInvestments	79000000	USD
CY2017	us-gaap	Other Nonoperating Income Expense OtherNonoperatingIncomeExpense	51000000	USD
CY2017	us-gaap	Gains Losses On Extinguishment Of Debt GainsLossesOnExtinguishmentOfDebt	-49000000	USD
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CY2017	us-gaap	Nonoperating Income Expense NonoperatingIncomeExpense	-648000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Before Income Taxes Extraordinary Items Noncontrolling Interest IncomeLossFromContinuingOperationsBeforeIncomeTaxesExtraordinaryItemsNoncontrollingInterest	-1389000000	USD
CY2017	us-gaap	Income Tax Expense Benefit IncomeTaxExpenseBenefit	-44000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-1345000000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-992000000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	-2337000000	USD
CY2017	us-gaap	Net Income Loss Attributable To Noncontrolling Interest NetIncomeLossAttributableToNoncontrollingInterest	-184000000	USD
CY2017	us-gaap	Net Income Loss NetIncomeLoss	-2153000000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	-2337000000	USD
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CY2017	us-gaap	Other Comprehensive Income Loss Foreign Currency Transaction And Translation Adjustment Net Of Tax OtherComprehensiveIncomeLossForeignCurrencyTransactionAndTranslationAdjustmentNetOfTax	12000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Available For Sale Securities Adjustment Net Of Tax OtherComprehensiveIncomeLossAvailableForSaleSecuritiesAdjustmentNetOfTax	-8000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Pension And Other Postretirement Benefit Plans Adjustment Net Of Tax OtherComprehensiveIncomeLossPensionAndOtherPostretirementBenefitPlansAdjustmentNetOfTax	-46000000	USD
CY2017	us-gaap	Other Comprehensive Income Loss Net Of Tax OtherComprehensiveIncomeLossNetOfTax	63000000	USD
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CY2017	us-gaap	Comprehensive Income Net Of Tax ComprehensiveIncomeNetOfTax	-2095000000	USD
CY2017	us-gaap	Profit Loss ProfitLoss	-2337000000	USD
CY2017	us-gaap	Income Loss From Discontinued Operations Net Of Tax Attributable To Reporting Entity IncomeLossFromDiscontinuedOperationsNetOfTaxAttributableToReportingEntity	-992000000	USD
CY2017	us-gaap	Income Loss From Continuing Operations Including Portion Attributable To Noncontrolling Interest IncomeLossFromContinuingOperationsIncludingPortionAttributableToNoncontrollingInterest	-1345000000	USD
CY2017	nrg	Income Lossfrom Equity Method Investmentof Unconsolidated Affiliates IncomeLossfromEquityMethodInvestmentofUnconsolidatedAffiliates	-102000000	USD
CY2017	us-gaap	Depreciation Amortization And Accretion Net DepreciationAmortizationAndAccretionNet	596000000	USD
CY2017	us-gaap	Accretion Expense Including Asset Retirement Obligations AccretionExpenseIncludingAssetRetirementObligations	44000000	USD
CY2017	us-gaap	Provision For Doubtful Accounts ProvisionForDoubtfulAccounts	68000000	USD
CY2017	us-gaap	Amortization Of Power Contracts Emission Credits AmortizationOfPowerContractsEmissionCredits	51000000	USD
CY2017	us-gaap	Amortization Of Financing Costs And Discounts AmortizationOfFinancingCostsAndDiscounts	29000000	USD
CY2017	nrg	Gains Losses On Extinguishment Of Debt Non Cash Portion GainsLossesOnExtinguishmentOfDebtNonCashPortion	-49000000	USD
CY2017	nrg	Amortization Of Intangibles And Out Of Market Contracts AmortizationOfIntangiblesAndOutOfMarketContracts	54000000	USD
CY2017	us-gaap	Share Based Compensation ShareBasedCompensation	35000000	USD
CY2017	us-gaap	Gain Loss On Disposition Of Assets1 GainLossOnDispositionOfAssets1	9000000	USD
CY2017	nrg	Impairment Losses ImpairmentLosses	1614000000	USD
CY2017	us-gaap	Increase Decrease In Derivative Assets And Liabilities IncreaseDecreaseInDerivativeAssetsAndLiabilities	170000000	USD
CY2017	us-gaap	Increase Decrease In Income Taxes IncreaseDecreaseInIncomeTaxes	13000000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	512000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities Continuing Operations NetCashProvidedByUsedInOperatingActivitiesContinuingOperations	856000000	USD
CY2017	us-gaap	Payments To Acquire Available For Sale Securities Debt PaymentsToAcquireAvailableForSaleSecuritiesDebt	512000000	USD
CY2017	us-gaap	Proceeds From Sale Of Available For Sale Securities Debt ProceedsFromSaleOfAvailableForSaleSecuritiesDebt	501000000	USD
CY2017	us-gaap	Cash Provided By Used In Operating Activities Discontinued Operations CashProvidedByUsedInOperatingActivitiesDiscontinuedOperations	754000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Operating Activities NetCashProvidedByUsedInOperatingActivities	1610000000	USD
CY2017	nrg	Intercompany Dividend Proceeds Investing IntercompanyDividendProceedsInvesting	0	USD
CY2017	us-gaap	Payments To Acquire Businesses Net Of Cash Acquired PaymentsToAcquireBusinessesNetOfCashAcquired	14000000	USD
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CY2017	us-gaap	Proceeds From Sale Of Intangible Assets ProceedsFromSaleOfIntangibleAssets	66000000	USD
CY2017	us-gaap	Proceeds From Sale Of Other Productive Assets ProceedsFromSaleOfOtherProductiveAssets	430000000	USD
CY2017	nrg	Investments In Proceeds From Sales Of Unconsolidated Affiliates InvestmentsInProceedsFromSalesOfUnconsolidatedAffiliates	-57000000	USD
CY2017	nrg	Net Contributions To Distributions From Discontinued Operations NetContributionsToDistributionsFromDiscontinuedOperations	150000000	USD
CY2017	us-gaap	Payments For Proceeds From Other Investing Activities PaymentsForProceedsFromOtherInvestingActivities	-30000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities Continuing Operations NetCashProvidedByUsedInInvestingActivitiesContinuingOperations	340000000	USD
CY2017	us-gaap	Cash Provided By Used In Investing Activities Discontinued Operations CashProvidedByUsedInInvestingActivitiesDiscontinuedOperations	-979000000	USD
CY2017	us-gaap	Proceeds From Payments To Minority Shareholders ProceedsFromPaymentsToMinorityShareholders	-30000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Investing Activities NetCashProvidedByUsedInInvestingActivities	-639000000	USD
CY2017	nrg	Intercompany Dividend Proceeds Financing IntercompanyDividendProceedsFinancing	0	USD
CY2017	us-gaap	Payments Of Dividends Preferred Stock And Preference Stock PaymentsOfDividendsPreferredStockAndPreferenceStock	38000000	USD
CY2017	us-gaap	Payments Of Debt Extinguishment Costs PaymentsOfDebtExtinguishmentCosts	42000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Common Stock ProceedsFromIssuanceOfCommonStock	-2000000	USD
CY2017	us-gaap	Proceeds From Issuance Of Long Term Debt ProceedsFromIssuanceOfLongTermDebt	1178000000	USD
CY2017	us-gaap	Payments Of Debt Issuance Costs PaymentsOfDebtIssuanceCosts	18000000	USD
CY2017	us-gaap	Repayments Of Other Debt RepaymentsOfOtherDebt	1884000000	USD
CY2017	us-gaap	Payments Of Distributions To Affiliates PaymentsOfDistributionsToAffiliates	125000000	USD
CY2017	us-gaap	Proceeds From Payments For Other Financing Activities ProceedsFromPaymentsForOtherFinancingActivities	-8000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities Continuing Operations NetCashProvidedByUsedInFinancingActivitiesContinuingOperations	-969000000	USD
CY2017	us-gaap	Cash Provided By Used In Financing Activities Discontinued Operations CashProvidedByUsedInFinancingActivitiesDiscontinuedOperations	-169000000	USD
CY2017	us-gaap	Net Cash Provided By Used In Financing Activities NetCashProvidedByUsedInFinancingActivities	-1138000000	USD
CY2017	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
CY2017	us-gaap	Net Cash Provided By Used In Discontinued Operations NetCashProvidedByUsedInDiscontinuedOperations	-394000000	USD
CY2017	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Period Increase Decrease Including Exchange Rate Effect CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsPeriodIncreaseDecreaseIncludingExchangeRateEffect	226000000	USD
CY2016Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	860000000	USD
CY2017Q4	us-gaap	Cash Cash Equivalents Restricted Cash And Restricted Cash Equivalents Including Disposal Group And Discontinued Operations CashCashEquivalentsRestrictedCashAndRestrictedCashEquivalentsIncludingDisposalGroupAndDiscontinuedOperations	1086000000	USD

Files In Submission

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$NRG
NRG ENERGY, INC. Stock $nrg

2019 Q4 Form 8-K Financial Statement

#000101387120000027 Filed on May 07, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NRG NRG ENERGY, INC. Stock $nrg

2019 Q4 Form 8-K Financial Statement

#000101387120000027 Filed on May 07, 2020

Income Statement

Balance Sheet

Cashflow Statement

Facts In Submission

Files In Submission

$NRG
NRG ENERGY, INC. Stock $nrg