XML 172 R142.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Commitments and Contingencies - Contingencies (Details 1) |  | 1 Months Ended | 7 Months Ended | 12 Months Ended | 29 Months Ended | 101 Months Ended |
--- | --- | --- | --- | --- | --- | --- | ---
Jun. 01, 2001 | Feb. 20, 2018 USD ($) | Jun. 30, 2010 Plaintiff | Mar. 10, 2010 Claim | Dec. 31, 2017 USD ($) lawsuit | Jul. 31, 2013 Claim | Dec. 31, 2017 USD ($) lawsuit Plaintiff | Dec. 31, 2012 Claim
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Nuclear insurance liability limit per incident |  |  |  |  | $ 13,440,000,000 |  | $ 13,440,000,000 |
Required nuclear liability insurance |  |  |  |  | 450,000,000 |  | 450,000,000 |
Nuclear financial protection pool mandated by the Price-Anderson Act |  |  |  |  | 13,000,000,000 |  | 13,000,000,000 |
Maximum assessment mandated by Price-Anderson Act per nuclear reactor for a nuclear incident |  |  |  |  | $ 127,000,000 |  | $ 127,000,000 |
Maximum assessment, administrative fee (as percent) |  |  |  |  | 5.00% |  | 5.00% |
Maximum annual assessment payment mandated by Price-Anderson Act for a nuclear incident |  |  |  |  | $ 19,000,000 |  | $ 19,000,000 |
Nuclear operator maximum annual assessment |  |  |  |  | $ 8,000,000 |  | $ 8,000,000 |
44% maximum assessment |  |  |  |  | 44.00% |  | 44.00% |
Maximum liability per nuclear incident |  |  |  |  | $ 112,000,000 |  | $ 112,000,000 |
Mutual property insurance additional blanket policy property coverage |  |  |  |  | 1,250,000,000 |  | 1,250,000,000 |
Nuclear property insurance coverage limit per individual insured |  |  |  |  | 1,500,000,000 |  | 1,500,000,000 |
Mutual Lost Revenue Insurance Maximum Weekly Recovery |  |  |  |  | 2,520,000 |  | 2,520,000 |
Accidental outage weekly recovery limit for loss revenues from a nuclear industry mutual insurance company in the event of insurable loss |  |  |  |  | $ 1,980,000 |  | $ 1,980,000 |
Multiplier that the industry mutual insurance company may assess against insureds premium |  |  |  |  | 10 |  | 10 |
The number of months a nuclear industry mutual insurance company will respond to retrospective premium adjustments |  |  |  |  | 24 months |  |  |
Number of years board of directors of industry mutual insurance company can adjust policy after policy expires |  |  |  |  | 6 years |  |  |
Telephone Consumer Protection Act Purported Class Actions |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Number of cases | lawsuit |  |  |  |  | 3 |  |  |
Damages sought |  |  |  |  | $ 1,500 |  |  |
Telephone Consumer Protection Act Purported Class Actions | California |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Number of cases | lawsuit |  |  |  |  |  |  | 1 |
Telephone Consumer Protection Act Purported Class Actions | New Jersey |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Number of cases | lawsuit |  |  |  |  |  |  | 2 |
CDWR and SDGE v Sunrise Power |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Damages sought |  |  |  |  | $ 1,200,000 |  |  |
Power Purchase Agreement (PPA) period | 10 years |  |  |  |  |  |  |
Remaining Term |  |  |  |  | 70 months |  |  |
Nuclear Event |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Total nuclear property insurance coverage |  |  |  |  | $ 2,750,000,000 |  | $ 2,750,000,000 |
Mutual Lost Revenue Insurance Maximum Weekly Recovery |  |  |  |  | 274,400,000 |  | 274,400,000 |
Accidental outage weekly recovery limit for loss revenues from a nuclear industry mutual insurance company in the event of insurable loss |  |  |  |  | 215,600,000 |  | 215,600,000 |
Non-nuclear Event |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Total nuclear property insurance coverage |  |  |  |  | 1,500,000,000 |  | 1,500,000,000 |
Mutual Lost Revenue Insurance Maximum Weekly Recovery |  |  |  |  | 183,500,000 |  | 183,500,000 |
Accidental outage weekly recovery limit for loss revenues from a nuclear industry mutual insurance company in the event of insurable loss |  |  |  |  | 144,000,000 |  | $ 144,000,000 |
Midwest Generation New Source Review |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Claims dismissed | Claim |  |  |  | 9 |  | 9 |  |
Pending claims | Claim |  |  |  | 10 |  | 10 |  | 1
Number of plaintiffs | Plaintiff |  |  | 1 |  |  |  | 1 |
Midwest Generation New Source Review | Minimum |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Pending claims | Plaintiff |  |  | 1 |  |  |  |  |
Midwest Generation New Source Review | Maximum |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Pending claims | Plaintiff |  |  | 10 |  |  |  |  |
Lignite Contract with Texas Westmoreland Coal Co. | Texas Westmoreland Coal Co. |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Bond obligation |  |  |  |  | $ 95,500,000 |  | $ 95,500,000 |
Subsequent Event |  |  |  |  |  |  |  |
Loss Contingencies [Line Items] |  |  |  |  |  |  |  |
Agreement to pay the State of Illinois and Federal Government |  | $ 500,000 |  |  |  |  |  |

X
- Definition This represents the additional policy for weekly lost revenues insured by a nuclear industry mutual insurance company. + References No definition available. + Details
Name: | nrg_AdditionalMutualLostRevenueInsuranceWeeklyMaximum
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition NRG’s percentage of ownership in STP. + References No definition available. + Details
Name: | nrg_FortyFourPercentMaximumAssessment
Namespace Prefix: | nrg_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition The industry mutual insurance company may assess the company: 10 times the amount of the total annual premium. + References No definition available. + Details
Name: | nrg_IndustryMutualInsuranceCompanyMultiplier
Namespace Prefix: | nrg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Loss Contingency, Number of Cases + References No definition available. + Details
Name: | nrg_LossContingencyNumberofCases
Namespace Prefix: | nrg_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition This represents the maximum total weekly recovery for lost revenues insured by a nuclear industry mutual insurance company. + References No definition available. + Details
Name: | nrg_MutualLostRevenueInsuranceMaximumWeeklyRecovery
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Additional property insurance coverage under a single limit blanket policy purchased from an industry mutual insurance company in order to insure property beyond the individual maximum coverage limit per insured. + References No definition available. + Details
Name: | nrg_MutualPropertyInsuranceAdditionalBlanketPolicyPropertyCoverage
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum coverage limit per individual insured for property insurance from an industry mutual insurance company. + References No definition available. + Details
Name: | nrg_MutualPropertyInsuranceIndividualMaximumPropertyCoverageLimit
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Total coverage for property insurance from an industry mutual insurance company. + References No definition available. + Details
Name: | nrg_MutualPropertyInsuranceTotalPropertyCoverage
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Nuclear Insurance Financial Protection Pool, Maximum Annual Assessment + References No definition available. + Details
Name: | nrg_NuclearInsuranceFinancialProtectionPoolMaximumAnnualAssessment
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum assessment to be paid per nuclear reactor for a nuclear incident under the financial protection pool mandated by the Price-Anderson Act. This assessment is paid by each United State nuclear reactor operator over multiple years at a limited amount per year in the event of an incident at any US nuclear reactor. + References No definition available. + Details
Name: | nrg_NuclearInsuranceFinancialProtectionPoolMaximumAssessment
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Nuclear Insurance Financial Protection Pool, Maximum Assessment, Administrative Fee, As a Percent + References No definition available. + Details
Name: | nrg_NuclearInsuranceFinancialProtectionPoolMaximumAssessmentAdministrativeFeeAsAPercent
Namespace Prefix: | nrg_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- Definition Nuclear Insurance Financial Protection Pool Nuclear Operator Maximum Annual Assessment + References No definition available. + Details
Name: | nrg_NuclearInsuranceFinancialProtectionPoolNuclearOperatorMaximumAnnualAssessment
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Maximum total assessment to be paid by a nuclear reactor for a nuclear incident under the financial protection pool mandated by the Price-Anderson Act. The total amount is calculated by multiplying the maximum assessment per nuclear reactor, by NRG’s ownership percentage. + References No definition available. + Details
Name: | nrg_NuclearInsuranceFinancialProtectionPoolNuclearOperatorTotalAssessment
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Nuclear Insurance Financial Protection Pool Value + References No definition available. + Details
Name: | nrg_NuclearInsuranceFinancialProtectionPoolValue
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Nuclear Insurance Per Incident Coverage Limit + References No definition available. + Details
Name: | nrg_NuclearInsurancePerIncidentCoverageLimit
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Nuclear Insurance Requirement Per Site + References No definition available. + Details
Name: | nrg_NuclearInsuranceRequirementPerSite
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition This represents the number of years after the policy expires that the industry mutual insurance company’s board of directors can make premium adjustments. + References No definition available. + Details
Name: | nrg_NumberOfYearsBoardOfDirectorsOfIndustryMutualInsuranceCompanyCanAdjustPolicyAfterPolicyExpires
Namespace Prefix: | nrg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition This represents number of months a nuclear industry mutual insurance company will respond to retrospective premium adjustments for policy purchased by company to guarantee financial obligations. + References No definition available. + Details
Name: | nrg_Periodofretrospectivepremiumadjustments
Namespace Prefix: | nrg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Represents the period of power purchase agreement + References No definition available. + Details
Name: | nrg_PowerPurchaseAgreementPeriod
Namespace Prefix: | nrg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Remaining Term + References No definition available. + Details
Name: | nrg_RemainingTerm
Namespace Prefix: | nrg_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Third Party Bond Obligation + References No definition available. + Details
Name: | nrg_ThirdPartyBondObligation
Namespace Prefix: | nrg_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount awarded to other party in judgment or settlement of litigation. + References No definition available. + Details
Name: | us-gaap_LitigationSettlementAmountAwardedToOtherParty
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_LossContingenciesLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of claims dismissed. + References No definition available. + Details
Name: | us-gaap_LossContingencyClaimsDismissedNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition The value (monetary amount) of the award the plaintiff seeks in the legal matter. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 9 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14557-108349 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyDamagesSoughtValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Number of plaintiffs that have filed claims pertaining to a loss contingency. + References No definition available. + Details
Name: | us-gaap_LossContingencyNumberOfPlaintiffs
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | duration

X
- Definition Number of pending claims pertaining to a loss contingency. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 450 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14435-108349 + Details
Name: | us-gaap_LossContingencyPendingClaimsNumber
Namespace Prefix: | us-gaap_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Details
Name: | us-gaap_LitigationCaseAxis=nrg_TelephoneConsumerProtectionActPurportedClassActionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=stpr_CA
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementGeographicalAxis=stpr_NJ
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LitigationCaseAxis=nrg_CDWRandSDGEvSunrisePowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=nrg_NuclearEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=nrg_NonnuclearEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LossContingenciesByNatureOfContingencyAxis=nrg_MidwestGenerationNewSourceReviewMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_UnrecordedUnconditionalPurchaseObligationByCategoryOfItemPurchasedAxis=nrg_LigniteContractwithTexasWestmorelandCoalCo.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | nrg_EconomicEntityAxis=nrg_TexasWestmorelandCoalCo.Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_SubsequentEventTypeAxis=us-gaap_SubsequentEventMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |