Property, Plant and Equipment [Abstract] Schedule of Property, Plant and Equipment [Table] Schedule of Property, Plant and Equipment [Table] Legal Entity [Axis] Legal Entity [Axis] Entity [Domain] Entity [Domain] NRG Yield NRG Yield [Member] NRG Yield [Member] Property, Plant and Equipment Property, Plant and Equipment [Line Items] Property, Plant and Equipment Disclosure Property, Plant and Equipment Disclosure [Text Block] Accounting for Derivative Instruments and Hedging Activities Disclosure [Abstract] -- None. No documentation exists for this element. -- Derivative [Table] Derivative [Table] Derivative Derivative [Line Items] Accounting for Derivative Instruments and Hedging Activities Derivative Instruments and Hedging Activities Disclosure [Text Block] Document And Entity Information [Abstract] -- None. No documentation exists for this element. -- Entity Registrant Name Entity Registrant Name Entity Central Index Key Entity Central Index Key Document Type Document Type Document Period End Date Document Period End Date Amendment Flag Amendment Flag Current Fiscal Year End Date Current Fiscal Year End Date Entity Current Reporting Status Entity Current Reporting Status Entity Filer Category Entity Filer Category Document Fiscal Year Focus Document Fiscal Year Focus Document Fiscal Period Focus Document Fiscal Period Focus Schedule of Stock by Class [Table] Schedule of Stock by Class [Table] Class of Stock [Axis] Class of Stock [Axis] Class of Stock [Domain] Class of Stock [Domain] Class A common stock Common Class A [Member] Class B common stock Common Class B [Member] Class of Stock Class of Stock [Line Items] Entity Common Stock, Shares Outstanding Entity Common Stock, Shares Outstanding Statement of Cash Flows [Abstract] Statement [Table] Statement [Table] Related Party [Axis] Related Party [Axis] Related Party [Domain] Related Party [Domain] Affiliate Affiliated Entity [Member] Non-affiliate Non-affiliated entity [Member] Non-affiliated entity [Member] Statement Statement [Line Items] Cash Flows from Operating Activities Net Cash Provided by (Used in) Operating Activities [Abstract] Net Income Net Income (Loss), Including Portion Attributable to Noncontrolling Interest Adjustments to reconcile net income to net cash (used)/provided by operating activities: Adjustments to Reconcile Net Income (Loss) to Cash Provided by (Used in) Operating Activities [Abstract] Distributions and equity in earnings of unconsolidated affiliates Income (Loss) from Equity Method Investments, Net of Dividends or Distributions Depreciation and amortization Depreciation, Depletion and Amortization Amortization of financing costs and debt discount/premiums Amortization of Financing Costs and Discounts Amortization of intangibles and out-of-market contracts Amortization of Intangibles and Out of Market Contracts The aggregate (income) expense recorded in earnings to allocate the cost of out-of-market contracts and intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash (income) expense, this element is added back to net income when calculating cash provided by (used in) operations using the indirect method. Changes in deferred income taxes Increase (Decrease) in Income Taxes Changes in derivative instruments Increase (Decrease) in Derivative Assets and Liabilities Changes in other working capital Increase (Decrease) in Other Operating Assets and Liabilities, Net Net Cash (Used)/Provided by Operating Activities Net Cash Provided by (Used in) Operating Activities Cash Flows from Investing Activities Net Cash Provided by (Used in) Investing Activities [Abstract] Capital expenditures Payments to Acquire Property, Plant, and Equipment (Increase)/decrease in restricted cash, net Increase (Decrease) in Restricted Cash Decrease/(increase) in notes receivable Increase (Decrease) in Notes Receivable The net change during the reporting period of amounts due from note holders for outstanding loans for both amounts due within one year (or one business cycle) and amounts due beyond one year. Proceeds from renewable energy grants Proceeds from Renewable Energy Grants The amount of cash received during the period for renewable energy grants related to capital projects. Investments in unconsolidated affiliates (Investments in) Proceeds From Sales of Unconsolidated Affiliates (Investments in) Proceeds From Sales of Unconsolidated Affiliates Net Cash Used by Investing Activities Net Cash Provided by (Used in) Investing Activities Cash Flows from Financing Activities Net Cash Provided by (Used in) Financing Activities [Abstract] Capital contributions from NRG Proceeds from Contributions from Parent Dividends and returns of capital to NRG Payments of Capital Distribution Proceeds from issuance of long-term debt — external Proceeds from Issuance of Long-term Debt Payment of debt issuance costs Payments of Debt Issuance Costs Payments for long-term debt Proceeds from (Repayments of) Debt Net Cash Provided by Financing Activities Net Cash Provided by (Used in) Financing Activities Net (Decrease)/Increase in Cash and Cash Equivalents Cash and Cash Equivalents, Period Increase (Decrease) Cash and Cash Equivalents at Beginning of Period Cash and Cash Equivalents, at Carrying Value Cash and Cash Equivalents at End of Period Statement of Financial Position [Abstract] Accumulated depreciation Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment Accumulated amortization Finite-Lived Intangible Assets, Accumulated Amortization Income Statement [Abstract] Operating Revenues Revenues [Abstract] Total operating revenues Revenues Operating Costs and Expenses Operating Costs and Expenses [Abstract] Cost of operations Cost of Revenue Depreciation and amortization General and administrative — affiliate General and Administrative Expense Total operating costs and expenses Costs and Expenses Operating Income Operating Income (Loss) Other Income/(Expense) Costs and Expenses [Abstract] Equity in earnings of unconsolidated affiliates Income (Loss) from Equity Method Investments Interest expense Interest Expense Total other expense Nonoperating Income (Expense) Income/(Loss) Before Income Taxes Income (Loss) from Continuing Operations before Income Taxes, Extraordinary Items, Noncontrolling Interest Income tax expense/(benefit) Income Tax Expense (Benefit) Net Income/(Loss) Segment Reporting Disclosure [Abstract] -- None. No documentation exists for this element. -- Schedule of Segment Reporting Information, by Segment [Table] Schedule of Segment Reporting Information, by Segment [Table] Segment Reporting Segment Reporting Information [Line Items] Segment Reporting Segment Reporting Disclosure [Text Block] Variable Interest Entities Disclosure [Abstract] -- None. No documentation exists for this element. -- Schedule of Variable Interest Entities [Table] Schedule of Variable Interest Entities [Table] Power Generation Facilities [Axis] Power Generation Facilities [Axis] The power generation facilities included in the entity's total global generation portfolio. Power Generation Facilities [Domain] Power Generation Facilities [Domain] Power Generation Facilities [Domain] GenConn Devon GenConn Devon [Member] GenConn Devon [Member] GenConn Middletown GenConn Middletown [Member] GenConn Middletown [Member] GenConn Energy LLC Gen Conn Energy LLC [Member] Represents the information pertaining to GenConn Energy LLC. Equity Method Investee, Name [Axis] Equity Method Investee, Name [Axis] Equity Method Investee, Name [Domain] Equity Method Investee, Name [Domain] GCE Holdings LLC GCE Holding LLC [Member] Represents the GCE Holding LLC GCE Holding LLC which wholly-owns GenConn Energy LLC. GenConn Energy LLC Variable Interest Entity Variable Interest Entity [Line Items] Economic interest in equity method investments (as a percent) Equity Method Investment, Ownership Percentage Power generation units Power Generation Units, Number The number of power generation units as of the balance sheet date. Power Generation Capacity (in MWs) Power Generation Capacity, Megawatts The generation capacity of the entity's power generation facilities as of the balance sheet date, expressed in megawatts. Number of Units Reached Commercial Operation at Peaking Generation Facilities Number of Units Reached Commercial Operation at Peaking Generation Facilities This element represents the number of units reached commercial operation at the peaking generation facilities during the period. Equity investments in affiliates Equity Method Investments Operating revenues Operating Income Assets, Current Assets, Current Assets, Noncurrent Assets, Noncurrent Liabilities, Current Liabilities, Current Liabilities, Noncurrent Liabilities, Noncurrent Fair Value of Financial Instruments Disclosure [Abstract] -- None. No documentation exists for this element. -- Fair Value, by Balance Sheet Grouping [Table] Fair Value, by Balance Sheet Grouping [Table] Concentration Risk Type [Axis] Concentration Risk Type [Axis] Concentration Risk Type [Domain] Concentration Risk Type [Domain] Credit Risk, Certain Long-term Agreements Credit Risk, Certain Long-term Agreements [Member] Credit Risk, Certain Long-term Agreements [Member] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Fair Value, by Balance Sheet Grouping, Disclosure Item Amounts [Axis] Fair Value, Disclosure Item Amounts [Domain] Fair Value, Disclosure Item Amounts [Domain] Carrying Amount Carrying (Reported) Amount, Fair Value Disclosure [Member] Fair Value Estimate of Fair Value, Fair Value Disclosure [Member] Fair Value of Financial Instruments Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items] Notes receivable Financing Receivable, Gross Long-term debt, including current portion Long-term Debt Concentration of Credit Risk Concentration of Credit Risk [Abstract] Concentration of Credit Risk [Abstract] Credit risk exposure under certain long-term agreements for the next five years Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure Period of credit risk exposure under certain long-term agreements (in years) Estimated Counterparty Credit Risk Exposure to Certain Counterparties, Period Estimated Counterparty Credit Risk Exposure to Certain Counterparties, Period Schedule of Segment Reporting Information, by Segment Schedule of Segment Reporting Information, by Segment [Table Text Block] Long Term Debt Disclosure [Abstract] -- None. No documentation exists for this element. -- Schedule of Long-term Debt Instruments [Table] Schedule of Long-term Debt Instruments [Table] Long-term Debt Disclosure Debt Instrument [Line Items] Schedule of Long-term Debt Schedule of Debt [Table Text Block] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value Measurements, Recurring and Nonrecurring [Table] Fair Value of Financial Instruments Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] Fair Value of Financial Instruments Fair Value Disclosures [Text Block] Summary of Significant Accounting Policies [Abstract] Summary of Significant Accounting Policies [Abstract] Summary of Significant Accounting Policies Significant Accounting Policies [Text Block] Equity Components [Axis] Equity Components [Axis] Equity Component [Domain] Equity Component [Domain] Summarized unaudited financial information for GCE Holdings LLC Schedule of Unaudited Fnancial Information [Table Text Block] Schedule of Unaudited Fnancial Information [Table Text Block] Statement of Other Comprehensive Income [Abstract] Net Income/(Loss) Other Comprehensive Income/(Loss), net of tax Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract] Unrealized gain/(loss) on derivatives, net of income tax expense of $13, $3, $15 and $5 Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax Other comprehensive income/(loss) Other Comprehensive Income (Loss), Net of Tax Comprehensive Income/(Loss) Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest Income Taxes Disclosure [Abstract] -- None. No documentation exists for this element. -- Income Tax Contingency [Table] Income Tax Contingency [Table] Income Taxes Income Tax Contingency [Line Items] Income Taxes Income Tax Disclosure [Text Block] Stockholders' Equity Note [Abstract] Counterparty Name [Axis] Counterparty Name [Axis] Counterparty Name [Domain] Counterparty Name [Domain] NRG NRG [Member] NRG [Member] Subsequent Event Type [Axis] Subsequent Event Type [Axis] Subsequent Event Type [Domain] Subsequent Event Type [Domain] Subsequent Event Subsequent Event [Member] Common stock Common Stock [Member] Preferred stock Preferred Stock [Member] Common Stock, Shares Authorized Common Stock, Shares Authorized Common Stock, Par Value Per Share Common Stock, Par or Stated Value Per Share Common Stock, Value, Issued Sale of Stock, Number of Shares Issued in Transaction Sale of Stock, Number of Shares Issued in Transaction Proceeds from Issuance Initial Public Offering Proceeds from Issuance Initial Public Offering Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs Adjustments to Additional Paid in Capital, Stock Issued, Issuance Costs Payments to Acquire Interest in Subsidiaries and Affiliates Payments to Acquire Interest in Subsidiaries and Affiliates Common Stock, Shares, Outstanding Common Stock, Shares, Outstanding Preferred Stock, Shares Authorized Preferred Stock, Shares Authorized Preferred Stock, Par or Stated Value Per Share Preferred Stock, Par or Stated Value Per Share Nature of Business Disclosure [Abstract] -- None. No documentation exists for this element. -- Nature of Business [Table] Nature of Business [Table] Nature of Business [Table] Nature of Business Nature of Business [Line Items] [Line Items] for Nature of Business [Table] IPO of NRG Yield IPO of NRG Yield [Table Text Block] [Table Text Block] for IPO of NRG Yield [Table] The Company's operating assets are comprised of the following projects: Schedule of Ownership Percentage, Net Capacity, Offtake Counterparty and Year of Offtake Expiration by Operating Asset [Table Text Block] Schedule of Ownership Percentage, Net Capacity, Offtake Counterparty and Year of Offtake Expiration by Operating Asset [Table Text Block] Schedule of Property, Plant and Equipment Property, Plant and Equipment [Table Text Block] Alpine Alpine [Member] Alpine [Member] Borrego Borrego [Member] Borrego [Member] Debt Instrument [Axis] Debt Instrument, Name [Domain] NRG Marsh Landing LLC, due 2017 and 2023 Marsh Landing Term Loan Facility [Member] GenOn Marsh Landing Term Loan Facility [Member] NRG Marsh Landing LLC, due 2017 Marsh Landing Term Loan Due 2017 [Member] GenOn Marsh Landing Term Loan Due 2017 [Member] NRG Marsh Landing LLC, due 2023 Marsh Landing Term Loan Due 2023 [Member] GenOn Marsh Landing Term Loan Due 2023 [Member] NRG Solar Alpine LLC, due 2013 and 2022 Alpine Financing Agreement [Member] Alpine Financing Agreement [Member] NRG Solar Alpine, due 2013 Alpine Financing Agreement, due 2013 [Member] Alpine Financing Agreement, due 2013 [Member] NRG Solar Alpine, due 2022 Alpine Financing Agreement, due 2022 [Member] Alpine Financing Agreement, due 2022 [Member] NRG Energy Center Minneapolis LLC, senior secured notes, due 2013, 2017, and 2025 NRG Energy Center Minneapolis LLC Senior Secured Notes [Member] Represents senior secured notes financed by NRG Energy Center Minneapolis LLC, which are due 2013, 2017, and 2025. NRG Energy Center Minneapolis LLC, senior secured notes, due 2013 NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2013 [Member] NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2013 [Member] NRG Energy Center Minneapolis LLC, senior secured notes, due 2017 NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2017 [Member] NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2017 [Member] NRG Energy Center Minneapolis LLC, senior secured notes, due 2025 NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2025 [Member] NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2025 [Member] NRG Solar Borrego I LLC, due 2024 and 2038 Borrego Financing [Member] Borrego Financing [Member] NRG Borrego I LLC, due 2024 Borrego Financing Agreement, due 2024 [Member] Borrego Financing Agreement, due 2024 [Member] NRG Borrego I LLC, due 2038 Borrego Financing Agreement, due 2038 [Member] Borrego Financing Agreement, due 2038 [Member] South Trent Wind LLC, due 2020 South Trent Financing Agreement [Member] South Trent Financing Agreement [Member] NRG Solar Avra Valley LLC, due 2031 Avra Valley Financing Agreement [Member] Avra Valley Financing Agreement [Member] NRG Roadrunner LLC, due 2031 Roadrunner Financing Agreement [Member] Roundrunner Financing Agreement [Member] NRG Solar Blythe LLC, due 2028 NRG Solar Blythe LLC Credit Agreement Due 2028 [Member] Represent NRG Solar Blythe LLC credit agreement, which is due 2028. PFMG and related subsidiaries, due 2030 PFMG Financing Agreement [Member] PFMG Financing Agreement [Member] Other Other Debt [Member] Represents other debt instruments not separately accounted disclosed. Note payable to NRG Energy, Inc. - South Trent South Trent Wind LLC [Member] Represents the information pertaining to South Trent Wind LLC. NRG Yield Revolving Credit Facility NRG Yield Revolving Credit Facility [Member] NRG Yield Revolving Credit Facility [Member] Long-term Debt, Type [Axis] Long-term Debt, Type [Domain] Letter of Credit Letter of Credit [Member] Fixed Rate Notes Fixed Rate Notes [Member] Fixed Rate Notes [Member] Cash Grant Loan Cash Grant Loan [Member] Cash Grant Loan [Member] Construction Loans Construction Loans [Member] Term Loan Facility Term Loan Facility [Member] Term Loan Facility [Member] Promissory Note Promissory Note [Member] Promissory Note [Member] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Axis] Variable Rate [Domain] Variable Rate [Domain] [Domain] for Variable Rate [Axis] London Interbank Offered Rate (LIBOR) London Interbank Offered Rate (LIBOR) [Member] London Interbank Offered Rate (LIBOR) [Member] Derivative Instrument Risk [Axis] Derivative Contract Type [Domain] Interest Rate Swaps Interest Rate Swap [Member] Long-term Debt Total long-term debt Long-term Debt and Capital Lease Obligations Variable rate basis Debt Instrument, Description of Variable Rate Basis Basis spread on variable rate Debt Instrument, Basis Spread on Variable Rate Interest rate Debt Instrument, Interest Rate, Stated Percentage Long-term Debt, Current Maturities Long-term Debt, Current Maturities Interest rate, minimum Debt Instrument, Interest Rate, Stated Percentage Rate Range, Minimum Interest rate, maximum Debt Instrument, Interest Rate, Stated Percentage Rate Range, Maximum Line of Credit Facility, Maximum Borrowing Capacity Line of Credit Facility, Maximum Borrowing Capacity Credit Facility, Maximum Borrowing Capacity, Amendment Credit Facility, Maximum Borrowing Capacity, Amendment Credit Facility, Maximum Borrowing Capacity, Amendment Line of Credit Facility, Increase, Additional Borrowings Line of Credit Facility, Increase, Additional Borrowings Long-term Construction Loan Long-term Construction Loan Letters of Credit Outstanding, Amount Adjustments to Additional Paid in Capital, Dividends in Excess of Retained Earnings Adjustments to Additional Paid in Capital, Dividends in Excess of Retained Earnings Proceeds from Contributions from Parent Debt Instrument, Face Amount Debt Instrument, Face Amount Debt Instrument, Escalation Percent of Basis Spread on Variable Rate Debt Instrument, Escalation Percent of Basis Spread on Variable Rate Debt Instrument, Escalation Percent of Basis Spread on Variable Rate Letters Of Credit, Availability Fee, Percentage Of Applicable Margin Letters Of Credit, Availability Fee, Percentage Of Applicable Margin Letters of Credit, Availability Fee, Percentage of Applicable Margin Number of Interest Rate Derivatives Held Number of Interest Rate Derivatives Held Derivative, Minimum Percent of Outstanding Notional Amount Required to Have Fixed Interest Rate Derivative, Minimum Percent of Outstanding Notional Amount Required to Have Fixed Interest Rate Derivative, Minimum Percent of Outstanding Notional Amount Required to Have Fixed Interest Rate Derivative, Fixed Interest Rate Derivative, Fixed Interest Rate Notional Amount of Interest Rate Derivatives Notional Amount of Interest Rate Derivatives Promissory Note Conversion into Equity Promissory Note Conversion into Equity Promissory Note Conversion into Equity Significant Accounting Policies [Abstract] Significant Accounting Policies [Abstract] Summary of Significant Accounting Policies [Table] Summary of Significant Accounting Policies [Table] Summary of Significant Accounting Policies [Table] Summary of Significant Accounting Policies Summary of Significant Accounting Policies Disclosure [Line Items] Use of Estimates (Policy) Use of Estimates [Policy Text Block] Describes an entity's accounting policy regarding estimates used in the preparation of financial statements in conformity with generally accepted accounting principles, which requires the use of management estimates. Segment Reporting (Policy) Segment Reporting, Policy [Policy Text Block] Business Segments [Axis] Business Segments [Axis] Segment [Domain] Segment [Domain] Conventional Generation Conventional Generation [Member] Conventional Generation [Member] Renewables Renewables [Member] Renewables [Member] Thermal Thermal [Member] Represents Thermal segment of the entity. Corporate Corporate [Member] Equity in earnings/(loss) of unconsolidated affiliates Income/(loss) before income taxes Net income/(loss) Net Income (Loss) Attributable to Parent Total assets Assets Business Acquisitions and Dispositions [Abstract] Business Acquisitions and Dispositions [Abstract] Schedule of Business Acquisitions, by Acquisition [Table] Schedule of Business Acquisitions, by Acquisition [Table] Debt Instrument [Axis] Debt Instrument, Name [Domain] Marsh Landing Term Loan Facility Business Acquisition [Axis] Business Acquisition [Axis] Business Acquisition, Acquiree [Domain] Business Acquisition, Acquiree [Domain] Marsh Landing Marsh Landing [Member] Marsh Landing [Member] Business Acquisition Business Acquisition [Line Items] Business Acquisition, Percentage of Voting Interests Acquired Business Acquisition, Percentage of Voting Interests Acquired Power Purchase Agreement Period Power Purchase Agreement Period Represents the period of power purchase agreement Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment, Adjusted Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment, Adjusted Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment, Adjusted Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted ASSETS Assets [Abstract] Current Assets Assets, Current [Abstract] Cash and cash equivalents Restricted cash Restricted Cash and Cash Equivalents, Current Accounts receivable Accounts Receivable, Net, Current Inventory Inventory, Net Notes receivable — external Notes, Loans and Financing Receivable, Net, Current Renewable energy grant receivable Grants Receivable, Current Deferred income taxes Deferred Tax Assets, Net, Current Prepayments and other current assets Prepaid Expense and Other Assets, Current Total current assets Property, plant and equipment, net of accumulated depreciation of $134 and $115 Property, Plant and Equipment, Net Other Assets Assets, Noncurrent [Abstract] Notes receivable Notes, Loans and Financing Receivable, Net, Noncurrent Intangible assets, net of accumulated amortization of $5 and $3 Finite-Lived Intangible Assets, Net Derivative instruments Derivative Instruments and Hedges, Noncurrent Other non-current assets Other Assets, Noncurrent Total other assets Total Other Assets Sum of the carrying amounts as of the balance sheet date of all assets, except for property, plant and equipment, that are expected to be realized in cash, sold or consumed after one year or beyond the normal operating cycle, if longer. Total Assets LIABILITIES AND STOCKHOLDERS’ EQUITY Liabilities and Equity [Abstract] Current Liabilities Liabilities, Current [Abstract] Current portion of long-term debt Long-term Debt and Capital Lease Obligations, Current Accounts payable Accounts Payable, Current Derivative instruments Derivative Liabilities, Current Accrued expenses and other current liabilities Accrued Expenses and Other Current Liabilities Sum of accrued expenses and other current liabilities. Accrued expenses are the carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, that are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Other current liabilities are the aggregate carrying amount, as of the balance sheet date, of current liabilities not separately disclosed in the balance sheet due to materiality considerations. Current liabilities are expected to be paid within one year (or the normal operating cycle, if longer). Total current liabilities Other Liabilities Liabilities, Noncurrent [Abstract] Long-term debt Deferred income taxes Deferred Tax Liabilities, Net, Noncurrent Derivative instruments Derivative Liabilities, Noncurrent Other non-current liabilities Other Liabilities, Noncurrent Total non-current liabilities Total Liabilities Liabilities Commitments and Contingencies Commitments and Contingencies Stockholders’ Equity Stockholders' Equity Attributable to Parent [Abstract] Common stock Receivable for issuance of common stock Receivable from Shareholders or Affiliates for Issuance of Capital Stock Additional paid-in capital Additional Paid in Capital, Common Stock Retained earnings Retained Earnings (Accumulated Deficit) Accumulated other comprehensive loss Accumulated Other Comprehensive Income (Loss), Net of Tax Total Stockholders’ Equity Stockholders' Equity, Including Portion Attributable to Noncontrolling Interest Total Liabilities and Stockholders’ Equity Liabilities and Equity Nature of Business Business Description and Basis of Presentation [Text Block] Net notional volume buy/(sell) of NRG Yield's open derivative transactions broken out by commodity Schedule of Notional Amounts of Outstanding Derivative Positions [Table Text Block] Fair value within the derivative instrument valuation on the balance sheets Schedule of Derivatives Instruments Statements of Financial Performance and Financial Position, Location [Table Text Block] Effects of NRG Yield's accumulated OCI balance attributable to interest rate swaps designated as cash flow hedge derivatives, net of tax Schedule of Cash Flow Hedges Included in Accumulated Other Comprehensive Income (Loss) [Table Text Block] Variable Interest Entity Variable Interest Entity [Text Block] Variable Interest Entity [Text Block] Range [Axis] Range [Axis] Range [Domain] Range [Domain] Minimum Minimum [Member] Maximum Maximum [Member] Avra Valley Avra Valley [Member] Avra Valley [Member] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Axis] Property, Plant and Equipment, Type [Domain] Property, Plant and Equipment, Type [Domain] Facilities and equipment Facilities And Equipment [Member] Represents long-lived, depreciable assets of facilities and equipment. Land and improvements Land and Land Improvements [Member] Construction in progress Construction in Progress [Member] Property, plant and equipment, gross Property, Plant and Equipment, Gross Accumulated depreciation Property, plant and equipment, net Renewable energy grant, gross Renewable energy grant, gross Renewable energy grant, gross Renewable energy grants, net Renewable energy grants, net Renewable energy grants, net Deferred tax asset, renewable energy grant Deferred tax asset, renewable energy grant Deferred tax asset, renewable energy grant Property, plant and equipment, useful life Property, Plant and Equipment, Useful Life Unrealized gain/(loss) on derivatives, income tax expense of Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Tax NRG Yield LLC NRG Yield LLC [Member] NRG Yield LLC [Member] NRG Yield, Inc. NRG Yield, Inc. [Member] NRG Yield, Inc. [Member] Effective Tax Rate Income Tax Expense (Benefit) [Abstract] Income/(loss) before income taxes Income tax expense/(benefit) Effective tax rate (as a percent) Effective Income Tax Rate, Continuing Operations Income Taxes Income Tax Disclosure [Abstract] Statutory income tax rate (as a percent) Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate Earnings taxable to NRG (as a percent) Partnership Earnings Taxable to Parent, As a Percent Partnership Earnings Taxable to Parent, As a Percent Limited Liability Company, ownership interest (as a percent) Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest Estimated carrying values and fair values of NRG Yield's recorded financial instruments Fair Value, by Balance Sheet Grouping [Table Text Block] Avenal Avenal [Member] Avenal [Member] Blythe NRG Solar Blythe LLC [Member] Represents NRG Solar Blythe LLC, a wholly-owned subsidiary of the entity. Roadrunner NRG Solar Roadrunner LLC [Member] NRG Solar Roadrunner LLC [Member] CVSR CVSR [Member] CVSR [Member] AZ DG Solar Projects AZ DG Solar Projects [Member] AZ DG Solar Projects [Member] PFMG DG Solar Projects PFMG DG Solar Projects [Member] PFMG DG Solar Projects [Member] South Trent South Trent Holding LLC [Member] South Trent Holding LLC [Member] Public Shareholders Public Shareholders [Member] Public Shareholders [Member] Class A common stock of NRG Yield Inc. Class B common stock of NRG Yield Inc. Class A units of NRG Yield LLC Capital Unit, Class A [Member] Power Generation Facilities by Type [Axis] Power Generation Facilities by Type [Axis] The types of power generation facilities included in the entity's total global generation portfolio. Power Generation Facilities, Type [Domain] Power Generation Facilities, Type [Domain] Listing of power generation facilities included in the entity's total global generation portfolio. Conventional Utility-Scale Solar Utility-Scale Solar [Member] Utility-Scale Solar [Member] Distributed Solar Distributed Solar [Member] Distributed solar generation capacity. Wind Wind Farms [Member] Wind farm generation capacity. Nature of Business Basis of Presentation [Line Items] Basis of Presentation [Line Items] Sale of Stock, Number of Shares Acquired in Transaction Sale of Stock, Number of Shares Acquired in Transaction Sale of Stock, Number of Shares Acquired in Transaction Common Stock, Voting Interest Common Stock, Voting Interest Common Stock, Voting Interest Percentage Ownership Percentage of Ownership Percentage of Ownership Steam and Chilled Water Capacity, Megawatts Thermal Equivalent Steam and Chilled Water Capacity, Megawatts Thermal Equivalent The generation capacity of the entity's thermal power generation facilities as of the balance sheet date, expressed in megawatts thermal equivalent. Power Generation Capacity, Reached Commercial Operations, Megawatts Power Generation Capacity, Reached Commercial Operations, Megawatts Power Generation Capacity, Reached Commercial Operations, Megawatts Allocation of Corporate Expenses Allocation of Corporate Expenses Allocation of Corporate Expenses Long-term Debt Long-term Debt [Text Block] Stockholders' Equity Stockholders' Equity Note Disclosure [Text Block] Measurement Unit [Axis] Measurement Unit [Axis] Represents information pertaining to various measurement units. Measurement Unit [Domain] Measurement Unit [Domain] Represents various measurement units used by the entity. MMbtu MMbtu [Member] Represents unit of measurement that is used to measure quantity of natural gas. Dollars United States of America, Dollars Derivatives by Underlying Assets [Axis] Derivatives by Underlying Assets [Axis] Derivatives by the underlying asset from which its value is derived. Underlying Assets [Domain] Underlying Assets [Domain] Major types of referenced/ underlying assets. Natural Gas Natural Gas [Member] Details pertaining to the natural gas, which is considered as a derivative commodity. Interest Interest [Member] Details pertaining to interest rate swaps which are considered a derivative commodity. Derivatives, Fair Value, by Derivative Instrument Risk [Axis] Derivative Contract Type [Domain] Interest rate contract Interest Rate Contract [Member] Interest rate contracts current Interest Rate Contract Current [Member] The current portion of a derivative instrument whose primary underlying risk is tied to the right to receive or pay a sum of money at a given interest rate. Interest rate contracts long-term Interest Rate Contract Non Current [Member] The noncurrent portion of a derivative instrument whose primary underlying risk is tied to the right to receive or pay a sum of money at a given interest rate. Commodity contracts current Commodity Contract Current [Member] The current portion of a derivative instrument whose primary underlying risk is tied to commodity prices. Hedging Designation [Axis] Hedging Designation [Domain] Derivatives Designated as Cash Flow Hedges Designated as Hedging Instrument [Member] Derivatives Not Designated as Cash Flow Hedges Not Designated as Hedging Instrument [Member] Volumetric Underlying Derivative Transactions Volumetric Underlying Derivative Transactions [Abstract] Volumetric Underlying Derivative Transactions [Abstract] Net notional volume buy of open derivative transactions, nonmonetary commodity (in MMbtu) Nonmonetary Notional Amount of Price Risk Derivatives Net notional volume buy of open derivative transactions, monetary commodity Fair Value of Derivative Instruments Derivative, Fair Value, Net [Abstract] Derivative Assets Derivative Asset, Fair Value, Gross Asset Derivative Liabilities Derivative Liability, Fair Value, Gross Liability Accumulated Other Comprehensive Income (Loss), Net of Tax Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract] Accumulated OCI beginning balance Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax Reclassified from accumulated OCI to income due to realization of previously deferred amounts Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net Mark-to-market of cash flow hedge accounting contracts Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss), Effective Portion, Net Accumulated OCI ending balance, net of tax of $2 and $5, respectively Accumulated OCI ending balance, tax Accumulated Other Comprehensive Income (Loss), Cumulative Change in Gain (Loss) from Cash Flow Hedges, Tax Amount Accumulated Other Comprehensive Income (Loss), Cumulative Change in Gain (Loss) from Cash Flow Hedges, Tax Amount Loss expected to be realized from OCI during the next 12 months, net of tax Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months Loss expected to be realized from OCI during the next 12 months, tax Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months, Tax The estimated tax impact of existing gains or losses on cash flow hedges, at the reporting date, which are expected to be reclassified to earnings within the next 12 months. Summary of Derivative Instruments Impact on Results of Operations Summary of Derivative Instruments Impact on Results of Operations [Abstract] Unrealized gain/(loss) on derivatives Unrealized Gain (Loss) on Derivatives Effective tax rate Income Tax Expense (Benefit) Continuing Operations [Text Block] Table shows the income tax expense and the related effective tax rate for the period. Schedule of Stock by Class Schedule of Stock by Class [Table Text Block] Business Acquisition Mergers, Acquisitions and Dispositions Disclosures [Text Block]