Clearway Energy (CWEN.A) 10-Q 4 Aug 15 2015 Q2 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	6 Months Ended
	Jun. 30, 2015	Jul. 31, 2015
Class of Stock [Line Items]
Entity Registrant Name	NRG Yield LLC
Entity Central Index Key	1,637,757
Document Type	10-Q
Document Period End Date	Jun. 30, 2015
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Document Fiscal Year Focus	2,015
Document Fiscal Period Focus	Q2
Common Class A [Member]
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		34,586,250
Common Class B [Member]
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		42,738,750
Common Class C [Member]
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		62,784,250
Common Class D [Member]
Class of Stock [Line Items]
Entity Common Stock, Shares Outstanding		42,738,750

Condensed Consolidated Statemen

Condensed Consolidated Statements of Operations - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Operating Revenues
Total operating revenues	$ 217	$ 173	[1]	$ 397	$ 313	[1]
Operating Costs and Expenses [Abstract]
Cost of operations	67	53	[1]	142	113	[1]
Depreciation and amortization	59	54	[1]	113	78	[1],[2]
General and administrative — affiliate	3	2		6	4
Business Combination, Integration Related Costs	1	0	[1]	1	0	[1]
Total operating costs and expenses	130	109	[1]	262	195	[1]
Operating Income	87	64	[1]	135	118	[1]
Costs and Expenses [Abstract]
Income (Loss) from Equity Method Investments	9	14	[1]	10	15	[1]
Other Nonoperating Income (Expense)	0	0	[1]	1	1	[1]
Gains (Losses) on Extinguishment of Debt	(7)	0		(7)	0
Interest expense	(42)	(33)	[1]	(111)	(59)	[1]
Total other expense, net	(40)	(19)	[1]	(107)	(43)	[1]
Net Income	47	45	[1],[3]	28	75	[1],[2],[3]
Net Income (Loss) Available to Common Stockholders, Basic	40	45		21	75
Net Income (Loss) Attributable to Parent	40			21
Affiliated Entity [Member]
Operating Costs and Expenses [Abstract]
General and administrative — affiliate	3	2	[1]	6	4	[1]
Noncontrolling Interest [Member]
Costs and Expenses [Abstract]
Net Income (Loss) Attributable to Noncontrolling Interest		0		7	0
Guarantor Subsidiaries [Member]
Operating Revenues
Total operating revenues	5	5		10	12
Operating Costs and Expenses [Abstract]
Cost of operations	3	3		7	8
Depreciation and amortization	1	1		2	2
General and administrative — affiliate	0	0		0	0
Business Combination, Integration Related Costs	0			0
Total operating costs and expenses	4	4		9	10
Operating Income	1	1		1	2
Costs and Expenses [Abstract]
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest expense	0	0		0	0
Total other expense, net	6	2		(19)	2
Net Income	7	3		(18)	4
Net Income (Loss) Attributable to Parent	7			(18)
Non-Guarantor Subsidiaries [Member]
Operating Revenues
Total operating revenues	213	168		379	301
Operating Costs and Expenses [Abstract]
Cost of operations	64	50		135	105
Depreciation and amortization	58	53		111	76
General and administrative — affiliate	0	0		0	0
Business Combination, Integration Related Costs	0			0
Total operating costs and expenses	122	103		246	181
Operating Income	91	65		133	120
Costs and Expenses [Abstract]
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				1	1
Gains (Losses) on Extinguishment of Debt	(7)			(7)
Interest expense	(30)	(28)		(87)	(53)
Total other expense, net	(37)	(28)		(93)	(52)
Net Income	54	37		40	68
Net Income (Loss) Attributable to Parent	58			44
NRG Yield Operating LLC [Member]
Operating Revenues
Total operating revenues	(1)	0		8	0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0	0
Depreciation and amortization	0	0		0	0
General and administrative — affiliate	3	2		6	4
Business Combination, Integration Related Costs	1			1
Total operating costs and expenses	4	2		7	4
Operating Income	(5)	(2)		1	(4)
Costs and Expenses [Abstract]
Income (Loss) from Equity Method Investments	9	14		10	15
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest expense	(12)	(5)		(24)	(6)
Total other expense, net	56	47		31	79
Net Income	51	45		32	75
Net Income (Loss) Attributable to Parent	40			21
Consolidation, Eliminations [Member]
Operating Revenues
Total operating revenues	0	0		0	0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0	0
Depreciation and amortization	0	0		0	0
General and administrative — affiliate	0	0		0	0
Business Combination, Integration Related Costs	0			0
Total operating costs and expenses	0	0		0	0
Operating Income	0	0		0	0
Costs and Expenses [Abstract]
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest expense	0	0		0	0
Total other expense, net	(105)	(85)		(47)	(147)
Net Income	(105)	(85)		(47)	(147)
Net Income (Loss) Attributable to Parent	(105)			(47)
NRG Yield LLC [Member]
Operating Revenues
Total operating revenues	0	0		0	$ 0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0
Depreciation and amortization	0	0		0
General and administrative — affiliate	0	0		0	$ 0
Business Combination, Integration Related Costs	0			0
Total operating costs and expenses	0	0		0	0
Operating Income	0	0		0	0
Costs and Expenses [Abstract]
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest expense	0	0		0	0
Total other expense, net	40	45		21	75
Net Income	40	$ 45		21	$ 75
Net Income (Loss) Attributable to Parent	$ 40			$ 21
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidated Stateme3

Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Other Comprehensive Loss, net of tax
Net Income	$ 47	$ 45	[1],[2]	$ 28	$ 75	[1],[2],[3]
Unrealized loss on derivatives	25	(22)	[2]	0	(34)	[2]
Other comprehensive loss	25	(22)	[2]	0	(34)	[2]
Comprehensive (Loss) Income	72	23		28	41
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	7	0		7	0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ 65	$ 23		$ 21	$ 41
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidated Balance

Condensed Consolidated Balance Sheets - Entity [Domain] - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Current Assets
Cash and cash equivalents	$ 281	$ 406	[1]
Restricted Cash and Cash Equivalents, Current	38	45	[1]
Accounts Receivable, Net, Current	98	85	[1]
Due from Affiliate, Current	2	0	[1]
Inventory, Net	29	27	[1]
Derivative Asset	4	0	[1]
Notes, Loans and Financing Receivable, Net, Current	7	6	[1]
Prepaid Expense and Other Assets, Current	19	21	[1]
Total current assets	478	590	[1]
Property, plant and equipment
In service	4,919	4,796	[1]
Under construction	8	8	[1]
Total property, plant and equipment	4,927	4,804	[1]
Less accumulated depreciation	(449)	(338)	[1]
Net property, plant and equipment	4,478	4,466	[1]
Other Assets
Equity Method Investments	549	227	[1]
Notes, Loans and Financing Receivable, Net, Noncurrent	13	15	[1]
Intangible assets, net of accumulated amortization of $64 and $36	1,389	1,423	[1]
Derivative Instruments and Hedges, Noncurrent	4	2	[1]
Other Assets, Noncurrent	133	103	[1]
Total other assets	2,088	1,770	[1]
Total Assets	7,044	6,826	[1]
Current Liabilities
Current portion of long-term debt	407	214	[1]
Accounts Payable, Current	23	20	[1]
Due to Affiliate, Current	60	45	[1]
Derivative Liability, Current	43	48	[1]
Accrued Expenses and Other Current Liabilities	37	61	[1]
Total current liabilities	570	388	[1]
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	3,744	4,247	[1]
Due to Affiliate, Noncurrent	618	337	[1]
Derivative Liability, Noncurrent	44	69	[1]
Other Liabilities, Noncurrent	52	49	[1]
Total non-current liabilities	4,458	4,702	[1]
Total Liabilities	$ 5,028	$ 5,090	[1]
Commitments and Contingencies
Stockholders' Equity
Members' Capital	$ 1,729	$ 1,609	[1]
Retained Earnings (Accumulated Deficit)	145	185	[1]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)	[1]
Stockholders' Equity Attributable to Noncontrolling Interest	200	0	[1]
Members' Equity	2,016	1,736	[1]
Total Liabilities and Stockholders’ Equity	$ 7,044	$ 6,826	[1]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidated Balance5

Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Intangible assets, accumulated amortization	$ 64	$ 36

Condensed Consolidated Stateme6

Condensed Consolidated Statements Of Cash Flows - USD ($) $ in Millions		6 Months Ended
		Jun. 30, 2015		Jun. 30, 2014
Cash Flows from Operating Activities
Net income/(loss)		$ 28		$ 75	[1],[2],[3]
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Distributions in excess of equity in earnings of unconsolidated affiliates		18		(8)	[2]
Depreciation and amortization		113		78	[1],[2]
Amortization of financing costs and debt discount/premiums		4		3	[2]
Amortization of intangibles and out-of-market contracts		26		1	[2]
Gains (Losses) on Extinguishment of Debt		7		0
Changes in derivative instruments		(35)		(5)	[2]
Changes in other working capital		(73)		(69)	[2]
Net Cash Provided by Operating Activities		88		75	[2]
Cash Flows from Investing Activities
Acquisition of businesses, net of cash acquired		(37)		0
Capital expenditures		(8)		(29)	[2]
(Increase) decrease in restricted cash		7		49	[2]
Increase (Decrease) in Notes Receivable		3		5	[2]
Proceeds from Renewable Energy Grants		0		137	[2]
(Investments in) Proceeds From Sales of Unconsolidated Affiliates		(313)		(15)	[2]
Payments for (Proceeds from) Other Investing Activities		0		11	[2]
Net Cash (Used in) Provided By Investing Activities		(837)		(178)	[2]
Cash Flows from Financing Activities
Distributions and return of capital to NRG				(25)
Proceeds from Issuance of Common Stock		600		0
Payments of Dividends		(61)		(44)	[2]
Proceeds from Issuance of Long-term Debt		287		41	[2]
Proceeds from Related Party Debt		281		337	[2]
Payments of Debt Issuance Costs		(4)		(5)
Proceeds from (Repayments of) Debt		598		154
Net Cash Provided by (Used in) Financing Activities		624		152	[2]
Net (Decrease) Increase in Cash and Cash Equivalents		(125)		49	[2]
Cash and Cash Equivalents at Beginning of Period		406	[4]	59	[2]
Cash and Cash Equivalents at End of Period		281		108	[2]
Proceeds from Noncontrolling Interests		119		0
Proceeds from Contributions from Parent				2
Affiliated Entity [Member]
Cash Flows from Financing Activities
Proceeds from Contributions from Parent		0		2
NRG [Member]
Cash Flows from Financing Activities
Distributions and return of capital to NRG		0
Non-affiliate
Cash Flows from Financing Activities
Proceeds from (Repayments of) Debt		(598)		(154)	[2]
El Segundo [Member] | NRG [Member]
Cash Flows from Financing Activities
Distributions and return of capital to NRG	[2]			(25)
Drop-down Acquisition [Member]
Cash Flows from Investing Activities
Acquisition of businesses, net of cash acquired		(489)		$ (336)
Additional Paid-in Capital [Member]
Cash Flows from Financing Activities
Proceeds from Issuance of Common Stock		$ 600
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[4]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Nature of Business

Nature of Business	6 Months Ended
	Jun. 30, 2015
Nature of Business Disclosure [Abstract]
Schedule of Ownership Percentage, Net Capacity, Offtake Counterparty and Year of Offtake Expiration by Operating Asset [Table Text Block]	As of June 30, 2015 , the Company's operating assets are comprised of the following projects: Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration Conventional GenConn Middletown 49.95 % 95 Connecticut Light & Power 2041 GenConn Devon 49.95 % 95 Connecticut Light & Power 2040 Marsh Landing 100 % 720 Pacific Gas and Electric 2023 El Segundo 100 % 550 Southern California Edison 2023 Walnut Creek 100 % 485 Southern California Edison 2023 1,945 Utility Scale Solar Alpine 100 % 66 Pacific Gas and Electric 2033 Avenal 49.95 % 23 Pacific Gas and Electric 2031 Avra Valley 100 % 25 Tucson Electric Power 2032 Blythe 100 % 21 Southern California Edison 2029 Borrego 100 % 26 San Diego Gas and Electric 2038 Roadrunner 100 % 20 El Paso Electric 2031 CVSR 48.95 % 122 Pacific Gas and Electric 2038 Kansas South 100 % 20 Pacific Gas and Electric 2033 TA High Desert 100 % 20 Southern California Edison 2033 Desert Sunlight 250 25 % 63 Southern California Edison 2035 Desert Sunlight 300 25 % 75 Pacific Gas and Electric 2040 481 Distributed Solar AZ DG Solar Projects 100 % 5 Various 2025 - 2033 PFMG DG Solar Projects 51 % 5 Various 2032 10 Wind Alta I 100 % 150 Southern California Edison 2035 Alta II 100 % 150 Southern California Edison 2035 Alta III 100 % 150 Southern California Edison 2035 Alta IV 100 % 102 Southern California Edison 2035 Alta V 100 % 168 Southern California Edison 2035 Alta X (b) 100 % 137 Southern California Edison 2038 (c) Alta XI (b) 100 % 90 Southern California Edison 2038 (c) South Trent 100 % 101 AEP Energy Partners 2029 Laredo Ridge 100 % 80 Nebraska Public Power District 2031 Taloga 100 % 130 Oklahoma Gas & Electric 2031 Pinnacle 100 % 55 Maryland Department of General Services and University System of Maryland 2031 Buffalo Bear 100 % 19 Western Farmers Electric Co-operative 2033 Spring Canyon II (b) 90.1 % 31 Platte River Power Authority 2038 Spring Canyon III (b) 90.1 % 26 Platte River Power Authority 2039 1,389 Thermal Thermal equivalent MWt (d) 100 % 1,310 Various Various Thermal generation 100 % 124 Various Various Total net capacity (excluding equivalent MWt) 3,949 (a) Net capacity represents the maximum, or rated, generating capacity of the facility multiplied by the Company's percentage ownership in the facility as of June 30, 2015 . (b) Projects are part of tax equity arrangements, as further described in Note 2, Summary of Significant Accounting Policies . (c) PPA begins on January 1, 2016. (d) For thermal energy, net capacity represents MWt for steam or chilled water and excludes 134 MWt available under the right-to-use provisions contained in agreements between two of the Company's thermal facilities and certain of its customers.
Business Description and Basis of Presentation [Text Block]	Note 1 — Nature of Business NRG Yield LLC, or the Company, was formed by NRG Energy, Inc., or NRG, as a Delaware limited liability company on March 5, 2013, to serve as the primary vehicle through which NRG owns, operates and acquires contracted renewable and conventional generation and thermal infrastructure assets. NRG owns 100% of the Company's Class B units and Class D units and receives distributions through its ownership of these units. NRG Yield, Inc., or Yield, Inc., owns 100% of the Company's Class A units and Class C units. NRG Yield LLC, through its wholly owned subsidiary, NRG Yield Operating LLC, or Yield Operating LLC, holds a portfolio of renewable and conventional generation and thermal infrastructure assets, primarily located in the Northeast, Southwest and California regions of the U.S. On June 29, 2015, Yield, Inc. issued 28,198,000 shares of Class C common stock at a price of $22 per share. Net proceeds to Yield, Inc. from the sale of the Class C common stock were $600 million , net of underwriting discounts and commissions of $20 million . Yield, Inc. utilized the proceeds of the offering to acquire 28,198,000 Class C units of the Company increasing its voting interest to 44.9% and its economic interest to 53.3% . Yield, Inc. consolidates the results of the Company through its controlling interest as sole managing member. The following table represents the structure of the Company as of June 30, 2015 : As of June 30, 2015 , the Company's operating assets are comprised of the following projects: Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration Conventional GenConn Middletown 49.95 % 95 Connecticut Light & Power 2041 GenConn Devon 49.95 % 95 Connecticut Light & Power 2040 Marsh Landing 100 % 720 Pacific Gas and Electric 2023 El Segundo 100 % 550 Southern California Edison 2023 Walnut Creek 100 % 485 Southern California Edison 2023 1,945 Utility Scale Solar Alpine 100 % 66 Pacific Gas and Electric 2033 Avenal 49.95 % 23 Pacific Gas and Electric 2031 Avra Valley 100 % 25 Tucson Electric Power 2032 Blythe 100 % 21 Southern California Edison 2029 Borrego 100 % 26 San Diego Gas and Electric 2038 Roadrunner 100 % 20 El Paso Electric 2031 CVSR 48.95 % 122 Pacific Gas and Electric 2038 Kansas South 100 % 20 Pacific Gas and Electric 2033 TA High Desert 100 % 20 Southern California Edison 2033 Desert Sunlight 250 25 % 63 Southern California Edison 2035 Desert Sunlight 300 25 % 75 Pacific Gas and Electric 2040 481 Distributed Solar AZ DG Solar Projects 100 % 5 Various 2025 - 2033 PFMG DG Solar Projects 51 % 5 Various 2032 10 Wind Alta I 100 % 150 Southern California Edison 2035 Alta II 100 % 150 Southern California Edison 2035 Alta III 100 % 150 Southern California Edison 2035 Alta IV 100 % 102 Southern California Edison 2035 Alta V 100 % 168 Southern California Edison 2035 Alta X (b) 100 % 137 Southern California Edison 2038 (c) Alta XI (b) 100 % 90 Southern California Edison 2038 (c) South Trent 100 % 101 AEP Energy Partners 2029 Laredo Ridge 100 % 80 Nebraska Public Power District 2031 Taloga 100 % 130 Oklahoma Gas & Electric 2031 Pinnacle 100 % 55 Maryland Department of General Services and University System of Maryland 2031 Buffalo Bear 100 % 19 Western Farmers Electric Co-operative 2033 Spring Canyon II (b) 90.1 % 31 Platte River Power Authority 2038 Spring Canyon III (b) 90.1 % 26 Platte River Power Authority 2039 1,389 Thermal Thermal equivalent MWt (d) 100 % 1,310 Various Various Thermal generation 100 % 124 Various Various Total net capacity (excluding equivalent MWt) 3,949 (a) Net capacity represents the maximum, or rated, generating capacity of the facility multiplied by the Company's percentage ownership in the facility as of June 30, 2015 . (b) Projects are part of tax equity arrangements, as further described in Note 2, Summary of Significant Accounting Policies . (c) PPA begins on January 1, 2016. (d) For thermal energy, net capacity represents MWt for steam or chilled water and excludes 134 MWt available under the right-to-use provisions contained in agreements between two of the Company's thermal facilities and certain of its customers. Substantially all of the Company's generation assets are under long-term contractual arrangements for the output or capacity from these assets. The thermal assets are comprised of district energy systems and combined heat and power plants that produce steam, hot water and/or chilled water and, in some instances, electricity at a central plant. Three of the district energy systems are subject to rate regulation by state public utility commissions while the other district energy systems have rates determined by negotiated bilateral contracts. In connection with the initial public offering of Yield, Inc. in 2013, the Company entered into a management services agreement with NRG for various services, including human resources, accounting, tax, legal, information systems, treasury, and risk management. Costs incurred by the Company under this agreement were $6 million and $4 million for the six months ended June 30, 2015 , and 2014 , respectively, which included certain direct expenses incurred by NRG on behalf of the Company. As described in Note 3 , Business Acquisitions , on January 2, 2015, the Company acquired the Laredo Ridge, Tapestry, and Walnut Creek projects, or the January 2015 Drop Down Assets, for total cash consideration of $489 million , including $9 million for working capital, plus assumed debt of $737 million . Additionally, on June 30, 2014, the Company acquired the TA High Desert, Kansas South, and El Segundo projects, or the June 2014 Drop Down Assets, from NRG for total cash consideration of $357 million plus assumed project level debt. These acquisitions were accounted for as transfers of entities under common control. The accounting guidance requires retrospective combination of the entities for all periods presented as if the combination has been in effect since the inception of common control. Accordingly, the Company prepared its consolidated financial statements to reflect the transfer as if it had taken place from the beginning of the financial statements period, or from the date the entities were under common control, which was April 1, 2014, for the January 2015 Drop Down Assets, which represents the date these entities were acquired by NRG. The accompanying unaudited interim consolidated financial statements have been prepared in accordance with the SEC’s regulations for interim financial information. Accordingly, they do not include all of the information and notes required by U.S. GAAP for complete financial statements. The following notes should be read in conjunction with the accounting policies and other disclosures as set forth in the notes to the Company's annual financial statements for the year ended December 31, 2014, included in the Company's Prospectus dated June 22, 2015. Interim results are not necessarily indicative of results for a full year. In the opinion of management, the accompanying unaudited interim consolidated financial statements contain all material adjustments consisting of normal and recurring accruals necessary to present fairly the Company's consolidated financial position as of June 30, 2015, and the results of operations, comprehensive income and cash flows for the six months ended June 30, 2015, and 2014.

Summary of Significant Accounti

Summary of Significant Accounting Policies	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Note 2 — Summary of Significant Accounting Policies Use of Estimates The preparation of consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions. These estimates and assumptions impact the reported amount of assets and liabilities and disclosures of contingent assets and liabilities as of the date of the consolidated financial statements. They also impact the reported amount of net earnings during the reporting period. Actual results could be different from these estimates. Tax Equity Arrangements Certain portions of the Company’s noncontrolling interest in subsidiaries represent third-party interests in the net assets under certain tax equity arrangements, which are consolidated by the Company, that have been entered into to finance the cost of wind facilities eligible for certain tax credits. Additionally, certain portions of the Company’s investments in unconsolidated affiliates reflect the Company’s interests in tax equity arrangements that are not consolidated by the Company that have been entered into to finance the cost of solar energy systems under operating leases eligible for certain tax credits. The Company has determined that the provisions in the contractual agreements of these structures represent substantive profit sharing arrangements. Further, the Company has determined that the appropriate methodology for calculating the noncontrolling interest and investment in unconsolidated affiliates that reflects the substantive profit sharing arrangements is a balance sheet approach utilizing the hypothetical liquidation book value, or HLBV, method. Under the HLBV method, the amounts reported as noncontrolling interests and investment in unconsolidated affiliates represent the amounts the investors that are party to the tax equity arrangements would hypothetically receive at each balance sheet date under the liquidation provisions of the contractual agreements, assuming the net assets of the funding structures were liquidated at their recorded amounts determined in accordance with GAAP. The investors’ interests in the results of operations of the funding structures are determined as the difference in noncontrolling interests and investment in unconsolidated affiliates at the start and end of each reporting period, after taking into account any capital transactions between the structures and the funds’ investors. The calculations utilized to apply the HLBV method include estimated calculations of taxable income or losses for each reporting period. Noncontrolling Interests The following table reflects the changes in the Company's noncontrolling interest balance: (In millions) Balance as of December 31, 2014 — Contributions from noncontrolling interest for Alta Wind X-X1 TE Holdco 119 Noncontrolling interest acquired in Spring Canyon acquisition 74 Comprehensive income 7 Balance as of June 30, 2015 $ 200 On June 30, 2015, Yield Operating LLC sold an economic interest in Alta TE Holdco, holder of the Alta Wind X and Alta Wind XI projects, to a financial institution in order to monetize cash and tax attributes, primarily production tax credits. The net proceeds of $119 million are reflected as noncontrolling interest in the Company's balance sheet. As described in Note 3, Business Acquisitions , the Company acquired Spring Canyon on May 7, 2015. The Company owns 90.1% of the Class B shares of Spring Canyon. The seller, Invenergy, owns the remaining 9.9% of the Class B shares and the Class A shares are owned by a tax equity investor. The interests of Invenergy and the tax equity investor of $74 million are shown as noncontrolling interests. Distributions On August 4, 2015 , NRG Yield LLC announced the declaration of a distribution on its Class A, Class B, Class C and Class D units of $0.21 per unit payable on September 15, 2015 to unit holders of record as of September 1, 2015 . On May 20, 2015, the Company declared a distribution on its Class A, Class B, Class C and Class D units of $0.20 per unit, which was paid on June 15, 2015. On February 17, 2015, the Company declared a distribution on its Class A and Class B units of $0.39 per unit, which was paid on March 16, 2015. Income Taxes The Company is classified as a partnership for federal and state income tax purposes. Therefore, federal and state income taxes are assessed at the partner level. Accordingly, no provision has been made for federal or state income taxes in the accompanying financial statements. Recent Accounting Developments ASU 2015-03 — In April 2015, the FASB issued ASU No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs , or ASU No. 2015-03. The amendments of ASU No. 2015-03 were issued to reduce complexity in the balance sheet presentation of debt issuance costs. ASU No. 2015-03 requires that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of debt liability, consistent with debt discounts or premiums. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this standard. The guidance in ASU No. 2015-03 is effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted for financial statements that have not been previously issued. Had the Company adopted this guidance early, other assets would have been lower by $ 55 million and $ 61 million with corresponding decreases in debt as of June 30, 2015, and December 31, 2014, respectively. The adoption of this standard will have no impact on the Company's results of operations, cash flows or net assets. ASU 2015-02 — In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis , or ASU No. 2015-02. The amendments of ASU No. 2015-02 were issued in an effort to minimize situations under previously existing guidance in which a reporting entity was required to consolidate another legal entity in which that reporting entity did not have: (1) the ability through contractual rights to act primarily on its own behalf; (2) ownership of the majority of the legal entity's voting rights; or (3) the exposure to a majority of the legal entity's economic benefits. ASU No. 2015-02 affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. All legal entities are subject to reevaluation under the revised consolidation model. The guidance in ASU No. 2015-02 is effective for periods beginning after December 15, 2015. Early adoption is permitted. The Company adopted the standard effective January 1, 2015 and the adoption of this standard did not impact the Company's results of operations, cash flows or financial position. ASU 2014-16 — In November 2014, the FASB issued ASU No. 2014-16, Derivatives and Hedging (Topic 815): Determining Whether the Host Contract in a Hybrid Financial Instrument Issued in the Form of a Share Is More Akin to Debt or to Equity , or ASU No. 2014-16. The amendments of ASU No. 2014-16 clarify how U.S. GAAP should be applied in determining whether the nature of a host contract is more akin to debt or equity and in evaluating whether the economic characteristics and risks of an embedded feature are "clearly and closely related" to its host contract. The guidance in ASU No. 2014-16 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The Company adopted the standard effective January 1, 2015 and the adoption of this standard did not impact the Company's results of operations, cash flows or financial position. ASU 2014-09 — In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , or ASU No. 2014-09. The amendments of ASU No. 2014-09 complete the joint effort between the FASB and the International Accounting Standards Board, or IASB, to develop a common revenue standard for U.S. GAAP and International Financial Reporting Standards, or IFRS, and to improve financial reporting. The guidance in ASU No. 2014-09 provides that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for the goods or services provided and establishes the following steps to be applied by an entity: (1) identify the contract with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) the entity satisfies the performance obligation. On July 9, 2015, the FASB voted to defer the effective date by one year to make the guidance of ASU No. 2014-09 effective for annual reporting periods beginning after December 15, 2017, including interim periods therein. Early adoption is permitted, but not prior to the original effective date, which was for annual reporting periods beginning after December 15, 2016. The Company is currently evaluating the impact of the standard on the Company's results of operations, cash flows and financial position.

Business Acquisitions

Business Acquisitions	6 Months Ended
	Jun. 30, 2015
Business Acquisition, Pro Forma Information [Table Text Block]	The following unaudited supplemental pro forma information represents the results of operations as if the Company had acquired the January 2015 Drop Down Assets on January 1, 2014, including the impact of acquisition accounting with respect to NRG's acquisition of the projects. For the six months ended (In millions) June 30, 2014 Operating revenues $ 339 Net income 71
Business Acquisition, Purchase Price [Table Text Block]	The purchase price of $923 million was provisionally allocated as follows: Acquisition Date Fair Value at December 31, 2014 Measurement period adjustments Revised Acquisition Date (In millions) Assets Cash $ 22 $ — $ 22 Current and non-current assets 49 (2 ) 47 Property, plant and equipment 1,304 6 1,310 Intangible assets 1,177 (6 ) 1,171 Total assets acquired 2,552 (2 ) 2,550 Liabilities Debt 1,591 — 1,591 Current and non-current liabilities 38 (2 ) 36 Total liabilities assumed 1,629 (2 ) 1,627 Net assets acquired $ 923 $ — $ 923
Business Acquisition	Note 3 — Business Acquisitions 2015 Acquisitions Desert Sunlight — On June 29, 2015, the Company acquired 25% of the membership interest in Desert Sunlight Investment Holdings, LLC, which owns two solar photovoltaic facilities that total 550 MW, located in Desert Center, California from EFS Desert Sun, LLC, an affiliate of GE Energy Financial Services for a purchase price of $285 million . Power generated by the facilities is sold to Southern California Edison and Pacific Gas and Electric under long-term PPAs with approximately 20 years and 25 years of remaining contract life, respectively. The Company accounts for its 25% investment as an equity method investment. Spring Canyon — On May 7, 2015, the Company acquired a 90.1% interest in Spring Canyon II, a 34 MW wind facility, and Spring Canyon III, a 29 MW wind facility, each located in Logan County, Colorado, from Invenergy Wind Global LLC. The purchase price was funded with cash on hand. Power generated by Spring Canyon II and Spring Canyon III is sold to Platte River Power Authority under long-term PPAs with approximately 24 years of remaining contract life. University of Bridgeport Fuel Cell — On April 30, 2015, the Company completed the acquisition of the University of Bridgeport Fuel Cell project in Bridgeport, Connecticut from FuelCell Energy, Inc. The project added an additional 1.4 MW of thermal capacity to the Company's portfolio, with a 12 year contract, with the option for a 7-year extension. The acquisition is reflected in the Company's Thermal segment. January 2015 Drop Down Assets from NRG — On January 2, 2015, the Company acquired the following projects from NRG: (i) Laredo Ridge, an 80 MW wind facility located in Petersburg, Nebraska, (ii) Tapestry, which includes Buffalo Bear, a 19 MW wind facility in Buffalo, Oklahoma; Taloga, a 130 MW wind facility in Putnum, Oklahoma; and Pinnacle, a 55 MW wind facility in Keyser, West Virginia, and (iii) Walnut Creek, a 485 MW natural gas facility located in City of Industry, California, for total cash consideration of $489 million , including $9 million for working capital, plus assumed project-level debt of $737 million . The Company funded the acquisition with cash on hand and drawings under its revolving credit facility. The assets and liabilities transferred to the Company relate to interests under common control by NRG and were recorded at historical cost in accordance with ASC 805-50, Business Combinations - Related Issues . The difference between the cash paid and the historical value of the entities' equity of $61 million , as well as $23 million of AOCL, was recorded as a distribution to NRG and reduced contributed capital. Since the transaction constituted a transfer of assets under common control, the guidance requires retrospective combination of the entities for all periods presented as if the combination has been in effect since the inception of common control. NRG acquired the majority of EME's assets, including Laredo Ridge, Tapestry and Walnut Creek, on April 1, 2014. The following table presents the historical information summary combining the financial information for the January 2015 Drop Down Assets transferred in connection with the acquisition: December 31, 2014 As Previously Reported Walnut Creek Tapestry Laredo Ridge As Currently Reported (In millions) Current assets $ 523 $ 46 $ 14 $ 7 $ 590 Property, plant and equipment 3,487 575 286 118 4,466 Non-current assets 1,603 57 61 49 1,770 Total assets 5,613 678 361 174 6,826 Debt 4,061 437 192 108 4,798 Other current and non-current liabilities 221 62 5 4 292 Total liabilities 4,282 499 197 112 5,090 Net assets $ 1,331 $ 179 $ 164 $ 62 $ 1,736 Supplemental Pro Forma Information As described above, the Company's acquisition of the January 2015 Drop Down Assets was accounted for as a transfer of entities under common control and all periods were retrospectively adjusted to reflect the entities as if they were transferred on the date the entities were under common control, which was April 1, 2014, the date NRG acquired Walnut Creek, Laredo Ridge and Tapestry. The following unaudited supplemental pro forma information represents the results of operations as if the Company had acquired the January 2015 Drop Down Assets on January 1, 2014, including the impact of acquisition accounting with respect to NRG's acquisition of the projects. For the six months ended (In millions) June 30, 2014 Operating revenues $ 339 Net income 71 Since the acquisition date, the January 2015 Drop Down Assets contributed $73 million in operating revenues and $23 million in net income. 2014 Acquisitions Alta Wind Portfolio Acquisition — On August 12, 2014, the Company acquired 100% of the membership interests of Alta Wind Asset Management Holdings, LLC, Alta Wind Company, LLC, Alta Wind X Holding Company, LLC and Alta Wind XI Holding Company, LLC, which collectively own seven wind facilities that total 947 MW located in Tehachapi, California and a portfolio of associated land leases, or the Alta Wind Portfolio. Power generated by the Alta Wind Portfolio is sold to Southern California Edison under long-term PPAs, with 21 years of remaining contract life for Alta Wind I-V. The Alta X and XI PPAs begin in 2016 with a term of 22 years and currently sell energy and renewable energy credits on a merchant basis. The purchase price for the Alta Wind Portfolio was $923 million , which consisted of a base purchase price of $870 million , as well as a payment for working capital of $53 million , plus the assumption of $1.6 billion of non-recourse project-level debt. In order to fund the purchase price, Yield, Inc. completed an equity offering of 12,075,000 shares of its Class A common stock at an offering price of $54.00 per share on July 29, 2014, which resulted in net proceeds of $630 million , after underwriting discounts and expenses. In addition, on August 5, 2014, Yield Operating LLC issued $500 million of Senior Notes, which bear interest at a rate of 5.375% and mature in August 2024. The acquisition was recorded as a business combination under ASC 805, with identifiable assets acquired and liabilities assumed provisionally recorded at their estimated fair values on the acquisition date. The initial accounting for the business combination is not complete because the evaluation necessary to assess the fair values of certain net assets acquired is still in process. The provisional amounts are subject to revision until the evaluations are completed to the extent that additional information is obtained about the facts and circumstances that existed as of the acquisition date. The allocation of the purchase price may be modified up to one year from the date of the acquisition as more information is obtained about the fair value of assets acquired and liabilities assumed. The following table summarizes the provisional amounts recognized for assets acquired and liabilities assumed as of December 31, 2014, as well as adjustments made through June 30, 2015. The purchase price of $923 million was provisionally allocated as follows: Acquisition Date Fair Value at December 31, 2014 Measurement period adjustments Revised Acquisition Date (In millions) Assets Cash $ 22 $ — $ 22 Current and non-current assets 49 (2 ) 47 Property, plant and equipment 1,304 6 1,310 Intangible assets 1,177 (6 ) 1,171 Total assets acquired 2,552 (2 ) 2,550 Liabilities Debt 1,591 — 1,591 Current and non-current liabilities 38 (2 ) 36 Total liabilities assumed 1,629 (2 ) 1,627 Net assets acquired $ 923 $ — $ 923 Fair value measurements The fair values of the property, plant and equipment and intangible assets were measured primarily based on significant inputs that are not observable in the market and thus represent a Level 3 measurement as defined in ASC 820. Significant inputs were as follows: • Property, plant and equipment — The fair values were determined primarily based on an income method using discounted cash flows and validated using a cost approach based on the replacement cost of the assets less economic obsolescence. The income approach was applied by determining the enterprise value for each acquired entity and subtracting the fair value of the intangible assets and working capital to determine the implied value of the tangible fixed assets. This methodology was primarily relied upon as the forecasted cash flows incorporate the specific attributes of each asset including age, useful life, equipment condition and technology. The income approach also allows for an accurate reflection of current and expected market dynamics such as supply and demand and regulatory environment as of the acquisition date. • Intangible Assets - PPAs — The fair values of the PPAs acquired were determined utilizing a variation of the income approach where the incremental future cash flows resulting from the acquired PPAs compared to the cash flows based on current market prices were discounted to present value at a weighted average cost of capital reflective of a market participant. The values were corroborated with available market data. The PPA values will be amortized over the term of the PPAs, which approximate 22 years . • Intangible Assets - Leasehold rights — The fair values of the leasehold rights acquired, which represent the contractual right to receive royalty payments equal to a percentage of PPA revenue from certain projects, were determined utilizing the income approach. The values were corroborated with available market data. The leasehold rights values will be amortized over a period of 21 years , which is equal to the average term of the contracts. June 2014 Drop Down Assets — On June 30, 2014, Yield Operating LLC acquired from NRG: (i) El Segundo, a 550 MW fast-start, gas-fired facility located in Los Angeles County, California; (ii) TA High Desert, a 20 MW solar facility located in Los Angeles County, California; and (iii) Kansas South, a 20 MW solar facility located in Kings County, California. Yield Operating LLC paid total cash consideration of $357 million , which represents a base purchase price of $349 million and $8 million of working capital adjustments. In addition, the acquisition included the assumption of $612 million of project-level debt. The assets and liabilities transferred to the Company relate to interests under common control by NRG and, were recorded at historical cost in accordance with ASC 805-50 . The difference between the cash proceeds and the historical value of the net assets was recorded as a distribution to NRG and reduced the balance of its contributed capital. Since the transaction constituted a transfer of entities under common control, the guidance requires retrospective combination of the entities for all periods presented as if the combination has been in effect since the inception of common control. Accordingly, the Company prepared its consolidated financial statements to reflect the transfer as if it had taken place from the beginning of the financial statements period.
EME-NYLD Assets [Member]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]

Property, Plant and Equipment

Property, Plant and Equipment	6 Months Ended
	Jun. 30, 2015
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment Disclosure	Note 4 — Property, Plant and Equipment The Company’s major classes of property, plant, and equipment were as follows: June 30, 2015 December 31, 2014 Depreciable Lives (In millions) Facilities and equipment $ 4,832 $ 4,709 2 - 40 Years Land and improvements 87 87 Construction in progress 8 8 Total property, plant and equipment 4,927 4,804 Accumulated depreciation (449 ) (338 ) Net property, plant and equipment $ 4,478 $ 4,466

Investments Accounted for by th

Investments Accounted for by the Equity Method and Variable Interest Entities	6 Months Ended
	Jun. 30, 2015
Equity Method Investments and Joint Ventures [Abstract]
Investments Accounted for by the Equity Method and Variable Interest Entities	Note 5 — Variable Interest Entities, or VIEs Entity that is Consolidated Alta TE Holdco — On June 30, 2015, the Company sold an economic interest in Alta TE Holdco, to a financial institution in order to monetize certain cash and tax attributes, primarily production tax credits. The financial institution, or Investor, receives 99% of allocations of taxable income and other items until the flip point, which occurs when the Investor obtains a specified return on its initial investment, at which time the allocations to the Investor change to 5% . The Company receives 100% of cash available for distribution in the first year and subsequently receives 94.34% until the flip point, at which time the allocations to the Company of cash available for distribution change to 97.12% , except if the flip point has not occurred by a specified date, which would result in 100% of cash available for distribution allocated to the Investor until the flip point occurs. Alta TE Holdco is a VIE and the Company is the primary beneficiary, through its position as managing member, and consolidates Alta TE Holdco. The net proceeds of $119 million are reflected as noncontrolling interest in the Company's balance sheet. The summarized financial information for Alta TE Holdco consisted of the following: (In millions) June 30, 2015 Other current and non-current assets $ 11 Property, plant and equipment 493 Intangible assets 287 Total assets 791 Current and non-current liabilities 8 Total liabilities 8 Noncontrolling interest 130 Net assets less noncontrolling interests $ 653 Entities that are not Consolidated The Company has interests in entities that are considered VIEs under ASC 810, Consolidation , but is not considered the primary beneficiary. The Company accounts for its interests in these entities under the equity method of accounting. NRG DGPV Holdco 1 LLC — On May 8, 2015, NRG Yield DGPV Holding LLC, a subsidiary of the Company, and NRG Renew LLC, a subsidiary of NRG, entered into a partnership by forming NRG DGPV Holdco 1 LLC, or DGPV Holdco, that will own or purchase solar power generation projects and other ancillary related assets via intermediate funds. On June 12, 2015, DGPV Holdco invested in a tax equity portfolio of distributed solar projects acquired from NRG Renew LLC. The portfolio agreed to pay NRG Renew LLC approximately $32 million for the acquired projects, of which approximately $7 million was paid in June 2015. The Company's initial investment in this portfolio was $4 million in cash and a $15 million payable into the portfolio, which it expects to pay during the third quarter of 2015. The Company's maximum exposure to loss is limited to its equity investment, which was $19 million as of June 30, 2015. NRG RPV Holdco 1 LLC — On April 9, 2015, NRG Yield RPV Holding LLC, a subsidiary of the Company, and NRG Residential Solar Solutions LLC, a subsidiary of NRG, entered into a partnership, by forming NRG RPV Holdco 1 LLC, or RPV Holdco, that will invest in and hold operating portfolios of residential solar assets developed by NRG Home Solar, a subsidiary of NRG, including: (i) an existing, unlevered portfolio of over 2,200 leases across nine states representing approximately 17 MW with a weighted average remaining lease term of approximately 17 years ; and (ii) in-development, tax equity financed portfolios of approximately 13,000 leases representing approximately 90 MW, with an average lease term for the existing and new leases of approximately 17 to 20 years . The following illustrates the structure of RPV Holdco: The Company invested $26 million in RPV Holdco in April 2015 related to the existing, unlevered portfolio of leases. The Company also invested $14 million of its $150 million commitment in the tax equity financed portfolios through June 30, 2015. Its maximum exposure will be limited to its equity investment. RPV Holdco is considered a VIE under ASC 810, however the Company is not the primary beneficiary, and will account for its investment under the equity method. The Company's maximum exposure to loss is limited to its equity investment, which was $40 million as of June 30, 2015. GenConn Energy LLC — The Company has a 49.95% interest in GCE Holding LLC, the owner of GenConn, which owns and operates two 190 MW peaking generation facilities in Connecticut at the Devon and Middletown sites. Each of these facilities was constructed pursuant to a 30-year cost of service type contract with the Connecticut Light & Power Company. GenConn is considered a VIE under ASC 810, however the Company is not the primary beneficiary, and accounts for its investment under the equity method. The project was funded through equity contributions from the owners and non-recourse, project-level debt. As of June 30, 2015 , the Company's investment in GenConn was $113 million and its maximum exposure to loss is limited to its equity investment. Additionally, GenConn has a $237 million project note with an interest rate of 4.73% and a maturity date of July 2041, and a 5-year, $35 million working capital facility that matures in 2018, which can be used to issue letters of credit at an interest rate of 1.875% per annum. As of June 30, 2015 , $224 million was outstanding under the note and nothing was drawn on the working capital facility. The note is secured by all of the GenConn assets. The following table presents summarized financial information for GCE Holding LLC: Three months ended June 30, Six months ended June 30, (in millions) 2015 2014 2015 2014 Income Statement Data: Operating revenues $ 18 $ 18 $ 40 $ 44 Operating income 11 10 20 20 Net income $ 8 $ 7 $ 14 $ 14 June 30, 2015 December 31, 2014 Balance Sheet Data: (In millions) Current assets $ 37 $ 33 Non-current assets 424 438 Current liabilities 16 20 Non-current liabilities $ 219 $ 223

Fair Value of Financial Instrum

Fair Value of Financial Instruments	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The Company records its derivative assets and liabilities at fair market value on its consolidated balance sheet. The following table presents assets and liabilities measured and recorded at fair value on the Company's consolidated balance sheets on a recurring basis and their level within the fair value hierarchy: As of June 30, 2015 As of December 31, 2014 Fair Value (a) Fair Value (a) (In millions) Level 2 Level 2 Derivative assets: Commodity contracts $ 4 $ — Interest rate contracts 4 2 Total assets 8 2 Derivative liabilities: Commodity contracts 3 3 Interest rate contracts 84 114 Total liabilities $ 87 $ 117 (a) There were no assets or liabilities classified as Level 1 or Level 3 as of June 30, 2015 , or December 31, 2014 .
Fair Value of Financial Instruments	Note 6 — Fair Value of Financial Instruments For cash and cash equivalents, restricted cash, accounts receivable, accounts payable, accounts payable — affiliate , accrued expenses and other liabilities, the carrying amounts approximate fair value because of the short-term maturity of those instruments and are classified as Level 1 within the fair value hierarchy. The estimated carrying amounts and fair values of the Company’s recorded financial instruments not carried at fair market value are as follows: As of June 30, 2015 As of December 31, 2014 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Assets: Notes receivable, including current portion $ 20 $ 20 $ 21 $ 21 Liabilities: Long-term debt — affiliate 618 643 337 386 Long-term debt, including current portion — external $ 4,151 $ 4,155 $ 4,461 $ 4,478 The fair value of notes receivable and long-term debt are based on expected future cash flows discounted at market interest rates, or current interest rates for similar instruments and are classified as Level 3 within the fair value hierarchy. Fair Value Accounting under ASC 820 ASC 820 establishes a fair value hierarchy that prioritizes the inputs to valuation techniques used to measure fair value into three levels as follows: • Level 1—quoted prices (unadjusted) in active markets for identical assets or liabilities that the Company has the ability to access as of the measurement date. • Level 2—inputs other than quoted prices included within Level 1 that are directly observable for the asset or liability or indirectly observable through corroboration with observable market data. • Level 3—unobservable inputs for the asset or liability only used when there is little, if any, market activity for the asset or liability at the measurement date. In accordance with ASC 820, the Company determines the level in the fair value hierarchy within which each fair value measurement in its entirety falls, based on the lowest level input that is significant to the fair value measurement. Recurring Fair Value Measurements The Company records its derivative assets and liabilities at fair market value on its consolidated balance sheet. The following table presents assets and liabilities measured and recorded at fair value on the Company's consolidated balance sheets on a recurring basis and their level within the fair value hierarchy: As of June 30, 2015 As of December 31, 2014 Fair Value (a) Fair Value (a) (In millions) Level 2 Level 2 Derivative assets: Commodity contracts $ 4 $ — Interest rate contracts 4 2 Total assets 8 2 Derivative liabilities: Commodity contracts 3 3 Interest rate contracts 84 114 Total liabilities $ 87 $ 117 (a) There were no assets or liabilities classified as Level 1 or Level 3 as of June 30, 2015 , or December 31, 2014 . Derivative Fair Value Measurements A majority of the Company's contracts are non-exchange-traded and valued using prices provided by external sources. For the Company’s energy markets, management receives quotes from multiple sources. To the extent that multiple quotes are received, the prices reflect the average of the bid-ask mid-point prices obtained from all sources believed to provide the most liquid market for the commodity. The remainder of the assets and liabilities represent contracts for which external sources or observable market quotes are not available. These contracts are valued using various valuation techniques including but not limited to internal models that apply fundamental analysis of the market and corroboration with similar markets. As of June 30, 2015 , there were no contracts valued with prices provided by models and other valuation techniques. The fair value of each contract is discounted using a risk free interest rate. In addition, a credit reserve is applied to reflect credit risk, which is calculated based on credit default swaps. To the extent that the net exposure is an asset, the Company uses the counterparty’s default swap rate. If the exposure is a liability, the Company uses its default swap rate. The credit reserve is added to the discounted fair value to reflect the exit price that a market participant would be willing to receive to assume the liabilities or that a market participant would be willing to pay for the assets. As of June 30, 2015 , the credit reserve resulted in a $1 million increase in fair value which is composed of a $1 million gain in OCI. It is possible that future market prices could vary from those used in recording assets and liabilities and such variations could be material. Concentration of Credit Risk Credit risk relates to the risk of loss resulting from non-performance or non-payment by counterparties pursuant to the terms of their contractual obligations. The Company monitors and manages credit risk through credit policies that include: (i) an established credit approval process; (ii) a daily monitoring of counterparties' credit limits; (iii) the use of credit mitigation measures such as margin, collateral, prepayment arrangements, or volumetric limits; (iv) the use of payment netting agreements; and (v) the use of master netting agreements that allow for the netting of positive and negative exposures of various contracts associated with a single counterparty. Risks surrounding counterparty performance and credit could ultimately impact the amount and timing of expected cash flows. The Company seeks to mitigate counterparty risk by having a diversified portfolio of counterparties. Counterparty credit exposure includes credit risk exposure under certain long-term agreements, including solar and other PPAs. As external sources or observable market quotes are not available to estimate such exposure, the Company estimates the exposure related to these contracts based on various techniques including but not limited to internal models based on a fundamental analysis of the market and extrapolation of observable market data with similar characteristics. Based on these valuation techniques, as of June 30, 2015 , credit risk exposure to these counterparties attributable to the Company's ownership interests was approximately $2.4 billion for the next five years . The majority of these power contracts are with utilities with strong credit quality and public utility commission or other regulatory support. However, such regulated utility counterparties can be impacted by changes in government regulations, which the Company is unable to predict.

Accounting for Derivative Instr

Accounting for Derivative Instruments and Hedging Activities	6 Months Ended
	Jun. 30, 2015
Accounting for Derivative Instruments and Hedging Activities Disclosure [Abstract]
Accounting for Derivative Instruments and Hedging Activities	Note 7 — Accounting for Derivative Instruments and Hedging Activities This footnote should be read in conjunction with the complete description under Note 7, Accounting for Derivative Instruments and Hedging Activities , to the Company's audited consolidated financial statements included in the Company's financial statements for the year ended December 31, 2014, included in the Company's Prospectus dated June 22, 2015. Energy-Related Commodities As of June 30, 2015 , the Company had forward contracts with an NRG subsidiary hedging the sale of power from the Alta X and Alta XI wind facilities extending through the end of 2015 and forward contracts for the purchase of fuel commodities relating to the forecasted usage of the Company’s district energy centers extending through 2017. At June 30, 2015 , these contracts were not designated as cash flow or fair value hedges. Interest Rate Swaps As of June 30, 2015 , the Company had interest rate derivative instruments on non-recourse debt extending through 2031, most of which are designated as cash flow hedges. Volumetric Underlying Derivative Transactions The following table summarizes the net notional volume buy/(sell) of the Company's open derivative transactions broken out by commodity as of June 30, 2015 , and December 31, 2014 . Total Volume June 30, 2015 December 31, 2014 Commodity Units (In millions) Natural Gas MMBtu 3 2 Interest Dollars $ 1,841 $ 2,817 The decrease in the interest rate position is primarily the result of settling the Alta X and Alta XI interest rate swaps in connection with the repayment of the outstanding project-level debt, as further described in Note 8, Long-term Debt . Fair Value of Derivative Instruments The following table summarizes the fair value within the derivative instrument valuation on the balance sheet: Fair Value Derivative Assets Derivative Liabilities June 30, 2015 December 31, 2014 June 30, 2015 December 31, 2014 (In millions) Derivatives Designated as Cash Flow Hedges: Interest rate contracts current $ — $ — $ 37 $ 40 Interest rate contracts long-term 4 2 42 49 Total Derivatives Designated as Cash Flow Hedges 4 2 79 89 Derivatives Not Designated as Cash Flow Hedges : Interest rate contracts current — — 3 5 Interest rate contracts long-term — — 2 20 Commodity contracts current 4 — 3 3 Total Derivatives Not Designated as Cash Flow Hedges 4 — 8 28 Total Derivatives $ 8 $ 2 $ 87 $ 117 The Company has elected to present derivative assets and liabilities on the balance sheet on a trade-by-trade basis and does not offset amounts at the counterparty master agreement level. As of June 30, 2015 , there was no outstanding collateral paid or received. The following table summarizes the offsetting of derivatives by counterparty master agreement level: Gross Amounts Not Offset in the Statement of Financial Position As of June 30, 2015 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ 4 $ (1 ) $ 3 Derivative liabilities (3 ) 1 (2 ) Total commodity contracts 1 — 1 Interest rate contracts: Derivative assets 4 (3 ) 1 Derivative liabilities (84 ) 3 (81 ) Total interest rate contracts (80 ) — (80 ) Total derivative instruments $ (79 ) $ — $ (79 ) Gross Amounts Not Offset in the Statement of Financial Position As of December 31, 2014 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ — $ — $ — Derivative liabilities (3 ) — (3 ) Total commodity contracts (3 ) — (3 ) Interest rate contracts: Derivative assets 2 (2 ) — Derivative liabilities (114 ) 2 (112 ) Total interest rate contracts (112 ) — (112 ) Total derivative instruments $ (115 ) $ — $ (115 ) Accumulated Other Comprehensive Loss The following table summarizes the effects on the Company’s accumulated OCL, balance attributable to interest rate swaps designated as cash flow hedge derivatives: Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 (In millions) Accumulated OCL beginning balance $ (83 ) $ (13 ) $ (58 ) $ (1 ) Reclassified from accumulated OCL to income due to realization of previously deferred amounts 4 4 7 7 Mark-to-market of cash flow hedge accounting contracts 21 (26 ) (7 ) (41 ) Accumulated OCL ending balance $ (58 ) $ (35 ) $ (58 ) $ (35 ) Losses expected to be realized from OCL during the next 12 months $ (17 ) $ (17 ) Amounts reclassified from accumulated OCL into income and amounts recognized in income from the ineffective portion of cash flow hedges are recorded to interest expense. There was no ineffectiveness for the three or six months ended June 30, 2015 , and 2014 . Impact of Derivative Instruments on the Statements of Operations The Company has interest rate derivative instruments that are not designated as cash flow hedges. The effect of interest rate hedges is recorded to interest expense. For the three months ended June 30, 2015 , and 2014 , the impact to the consolidated statements of operations was a gain of $31 million and a loss of $3 million , respectively. For the six months ended June 30, 2015 , and 2014 , the impact to the consolidated statements of operations was a gain of $19 million and a loss of $6 million , respectively. A portion of the Company’s derivative commodity contracts relate to its Thermal Business for the purchase of fuel commodities based on the forecasted usage of the thermal district energy centers. Realized gains and losses on these contracts are reflected in the fuel costs that are permitted to be billed to customers through the related customer contracts or tariffs and accordingly, no gains or losses are reflected in the consolidated statements of operations for these contracts. Commodity contracts also hedge the forecasted sale of power for the Alta X and Alta XI wind facilities until the start of the PPAs on January 1, 2016. The effect of these commodity hedges is recorded to operating revenues. For the three months ended June 30, 2015 , and 2014 , the impact to the consolidated statements of operations was an unrealized loss of $4 million and $0 million , respectively. For the six months ended June 30, 2015 , and 2014 , the impact to the consolidated statements of operations was an unrealized gain of $3 million and $0 million , respectively. See Note 6 , Fair Value of Financial Instruments , for discussion regarding concentration of credit risk.

Long-term Debt

Long-term Debt	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Long-term Debt	Note 8 — Long-term Debt This footnote should be read in conjunction with the complete description under Note 9, Long-term Debt, to the Company's financial statements for the year ended December 31, 2014 included in the Company's Prospectus dated June 22, 2015. Long-term debt consisted of the following: June 30, 2015 December 31, 2014 June 30, 2015, interest rate % (a) (In millions, except rates) Senior Notes, due 2024 $ 500 $ 500 5.375 Long-term debt - affiliate, due 2019 337 337 3.580 Long-term debt - affiliate, due 2020 281 — 3.325 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 267 — L+2.50 Project-level debt: Alta Wind I, lease financing arrangement, due 2034 255 261 7.015 Alta Wind II, lease financing arrangement, due 2034 200 205 5.696 Alta Wind III, lease financing arrangement, due 2034 208 212 6.067 Alta Wind IV, lease financing arrangement, due 2034 138 138 5.938 Alta Wind V, lease financing arrangement, due 2035 215 220 6.071 Alta Wind X, due 2021 — 300 L+2.00 Alta Wind XI, due 2021 — 191 L+2.00 Alta Realty Investments, due 2031 33 34 7.00 Alta Wind Asset Management, due 2031 19 20 L+2.375 NRG West Holdings LLC, due 2023 (El Segundo Energy Center) 489 506 L+1.625 - L+2.25 NRG Marsh Landing LLC, due 2017 and 2023 454 464 L+1.75 - L+1.875 Walnut Creek Energy, due 2023 381 391 L+1.625 Tapestry Wind LLC, due 2021 185 192 L+1.625 NRG Solar Alpine LLC, due 2014 and 2022 161 163 L+1.75 NRG Energy Center Minneapolis LLC, due 2017 and 2025 112 121 5.95 -7.25 Laredo Ridge LLC, due 2026 106 108 L+1.875 NRG Solar Borrego LLC, due 2025 and 2038 74 75 L+ 2.50/5.65 South Trent Wind LLC, due 2020 63 65 L+2.75 NRG Solar Avra Valley LLC, due 2031 62 63 L+1.75 TA High Desert LLC, due 2020 and 2032 54 55 L+2.50/5.15 WCEP Holdings LLC, due 2023 46 46 L+3.00 NRG Roadrunner LLC, due 2031 41 42 L+2.01 NRG Solar Kansas South LLC, due 2031 34 35 L+2.00 NRG Solar Blythe LLC, due 2028 22 22 L+2.75 PFMG and related subsidiaries financing agreement, due 2030 31 31 6.00 NRG Energy Center Princeton LLC, due 2017 1 1 5.95 Subtotal project-level debt: 3,384 3,961 Total debt 4,769 4,798 Less current maturities 407 214 Total long-term debt $ 4,362 $ 4,584 (a) As of June 30, 2015 , L+ equals 3 month LIBOR plus x%, except for the NRG Marsh Landing term loan, Walnut Creek term loan, and the Revolving Credit Facility where L+ equals 1 month LIBOR plus x% and Kansas South where L+ equals 6 month LIBOR plus x%. The financing arrangements listed above contain certain covenants, including financial covenants that the Company is required to be in compliance with during the term of the respective arrangement. As of June 30, 2015 , the Company was in compliance with all of the required covenants. The discussion below lists changes to or additions of long-term debt for the six months ended June 30, 2015 . Yield, Inc. 2020 Convertible Notes and Related Intercompany Note On June 29, 2015, Yield, Inc. closed on its offering of $287.5 million of 3.25% Convertible Notes due 2020, or the 2020 Convertible Notes. The 2020 Convertible Notes are convertible, under certain circumstances, into Yield, Inc.’s Class C common stock, cash or a combination thereof at an initial conversion price of $27.50 per Class C common share, which is equivalent to an initial conversion rate of approximately 36.3636 shares of Class C common stock per $1,000 principal amount of 2020 Convertible Notes. The Company and Yield Operating LLC provided a guarantee to Yield, Inc. with respect to the 2020 Convertible Notes. In addition, Yield Operating LLC and Yield, Inc. entered into an intercompany borrowing arrangement, under which Yield Operating LLC received $281 million of the proceeds of the 2020 Convertible Notes. The intercompany note bears interest at a rate of 3.325% and matures in 2020. NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility On June 26, 2015, the Company amended the revolving credit facility to, among other things, increase the availability from $450 million to $495 million . As of June 30, 2015, $267 million of borrowing and $32 million of letters of credit were outstanding. In July 2015, the Company repaid $190 million utilizing proceeds from the issuance of the 2020 Convertible Notes and the Yield, Inc. Class C common stock issuance. Alta Wind X and Alta Wind XI Due 2021 On June 30, 2015, Yield Operating LLC entered into a tax equity financing arrangement through which it has received $119 million in net proceeds, as described in Note 5 , Variable Interest Entities, or VIEs . These proceeds, as well as proceeds obtained from the June 29, 2015, Yield, Inc. common stock offering, as described in Note 1, Nature of Business , and 2020 Convertible Notes issuance, as described above, were utilized to repay all of the outstanding project indebtedness associated with the Alta Wind X and Alta Wind XI wind facilities. The Company also settled interest rate swaps associated with the project level debt for the Alta Wind X and Alta Wind XI wind facilities at a value of $17 million . Laredo Ridge On July 27, 2010, Laredo Ridge entered into a credit agreement with a group of lenders for a $75 million construction loan that was convertible to a term loan upon completion of the project, a $53 million cash grant loan and a $3 million working capital loan facility. The project met the conditions to convert to a term loan on March 18, 2011. The cash grant loan was repaid in July 2011 with proceeds of the cash grant. The credit agreement also included a letter of credit facility on behalf of Laredo Ridge of up to $9 million . Laredo Ridge paid a fee equal to the applicable margin on issued letters of credit. On December 17, 2014, Laredo Ridge amended the credit agreement to increase its term loan borrowings by an additional $41 million to reduce the working capital facility by $1 million , to increase the letter of credit facility by $1 million and to reduce the related interest rate to LIBOR plus 1.875% through December 31, 2018, LIBOR plus 2.125% from January 1, 2019 through December 31, 2023 and LIBOR plus 2.375% from January 1, 2024 through the maturity date. The fee on the working capital facility was reduced to 0.5% . In addition, the maturity date was extended to March 31, 2028. The proceeds were utilized to make a distribution of $33 million to NRG Wind LLC, an NRG subsidiary, with the remaining $8 million utilized to fund the costs of the amendment. As of June 30, 2015 , $106 million was outstanding under the term loan, nothing was outstanding under the working capital facility, and $10 million of letters of credit in support of the project were issued. In connection with the amendment to the credit agreement, Laredo Ridge entered into a series of fixed for floating interest rate swaps that would fix the interest rate for a minimum of 75% of the outstanding notional amount. Laredo Ridge pays its counterparty the equivalent of a 2.31% fixed interest payment on a predetermined notional value, and quarterly, Laredo Ridge will receive the equivalent of a floating interest payment based on the three-month LIBOR calculated on the same notional value through December 31, 2028. All interest rate swap payments by Laredo Ridge and its counterparties are made quarterly and LIBOR is determined in advance of each interest period. Tapestry Wind LLC On December 21, 2011, Tapestry Wind LLC entered into a credit agreement with a group of lenders for a $214 million term loan and an $8 million working capital loan facility. The term loan matures in December 2021. It is secured by Tapestry Wind LLC's interest in the Buffalo Bear, Taloga, and Pinnacle projects. The term loan amortizes based upon a predetermined schedule. The working capital facility is available to fund the operating needs of Tapestry Wind LLC. The commitment fee on this facility is 0.75% . The credit agreement also includes a letter of credit facility on behalf of Tapestry Wind LLC of up to $20 million . Tapestry Wind LLC pays a fee equal to the applicable margin on issued letters of credit. Under the terms of the agreement, Tapestry Wind LLC entered into a series of fixed for floating interest rate swaps that would fix the interest rate for a minimum of 90% of the outstanding notional amount. Tapestry Wind LLC will pay its counterparty the equivalent of a 2.21% fixed interest payment on a predetermined notional value, and quarterly, Tapestry Wind LLC will receive the equivalent of a floating interest payment based on a three-month LIBOR calculated on the same notional value through December 21, 2021. All interest rate swap payments by Tapestry Wind LLC and its counterparties are made quarterly and the LIBOR is determined in advance of each interest period. Swaps became effective December 30, 2011, and amortize in proportion to the term loan. At the same time Tapestry Wind LLC entered into a series of forward starting swaps to hedge the refinancing risk. The swaps are effective December 21, 2021. Tapestry Wind LLC will pay its counterparty the equivalent of a 3.57% fixed interest payment on a predetermined notional value, and quarterly, Tapestry Wind LLC will receive the equivalent of a floating interest payment based on a three-month LIBOR calculated on the same notional value through December 21, 2029. On November 12, 2014, Tapestry Wind LLC amended the credit agreement to reduce the related interest rate to LIBOR plus 1.625% through December 20, 2018 and LIBOR plus 1.75% from December 21, 2018 through the maturity date. As of June 30, 2015 , $185 million was outstanding under the term loan, nothing was outstanding under the working capital facility and $20 million of letters of credit in support of the project were issued. Walnut Creek On July 27, 2011, Walnut Creek entered into a credit agreement with a group of lenders for a $442 million construction loan that was convertible to a term loan upon completion of the project, and a $5 million working capital loan facility. The project met the conditions to convert to a term loan on June 21, 2013 and matures in May 2023. The term loan amortizes based upon a predetermined schedule. The working capital facility is available to fund the operating needs of Walnut Creek. The commitment fee on this facility is 0.625% . The Walnut Creek agreement also includes a letter of credit facility on behalf of Walnut Creek of up to $117 million . Walnut Creek pays a fee equal to the applicable margin on issued letters of credit. Under the terms of the agreement, Walnut Creek entered into a series of fixed for floating interest rate swaps that would fix the interest rate for a minimum of 90% of the outstanding notional amount. Walnut Creek will pay its counterparty the equivalent of a 3.54% fixed interest payment on a predetermined notional value, and quarterly, Walnut Creek will receive the equivalent of a floating interest payment based on a three-month LIBOR calculated on the same notional value through May 31, 2023. All interest rate swap payments by Walnut Creek and its counterparties are made quarterly and the LIBOR is determined in advance of each interest period. Swaps became effective June 28, 2013, and amortize in proportion to the term loan. On October 21, 2014, Walnut Creek amended the credit agreement to increase its term loan borrowings by an additional $10 million , and to reduce the related interest rate to LIBOR plus 1.625% through September 30, 2018, LIBOR plus 1.75% from October 1, 2018 through September 30, 2022, and LIBOR plus 1.875% from October 1, 2022, through the maturity date. The fee on the working capital facility was reduced to 0.5% . The proceeds were utilized to make a distribution of $6 million to WCEP Holdings LLC with the remaining $4 million utilized to fund the costs of the amendment. In addition, Walnut Creek entered into an additional interest rate swap to maintain the minimum of 90% of the outstanding notional amount being swapped to a fixed interest rate. Walnut Creek pays its counterparty the equivalent of a 4.0025% fixed interest payment on a predetermined notional value, and quarterly, Walnut Creek receives the equivalent of a floating interest payment based on a three-month LIBOR calculated on the same notional value through July 31, 2020. All interest rate swap payments by Walnut Creek and its counterparties are made quarterly and the LIBOR is determined in advance of each interest period. Swaps became effective June 28, 2013 and amortize in proportion to the term loan. As of June 30, 2015 , $381 million was outstanding under the term loan, nothing was outstanding under the working capital facility, and $61 million of letters of credit were issued. WCEP Holdings LLC On July 27, 2011, WCEP Holdings LLC entered into a credit agreement with a group of lenders for a $53 million construction loan that was convertible to a term loan upon completion of the Walnut Creek project. The Walnut Creek project met the conditions for the WCEP Holdings LLC loan to convert to a term loan on June 21, 2013. The term loan has an interest rate of LIBOR plus an applicable margin of 4% . The term loan matures in May 2023. The term loan amortizes based upon a predetermined schedule. Under the terms of the credit agreement, WCEP Holdings LLC entered into two fixed for floating interest rate swaps that would fix the interest rate for a minimum of 90% of the outstanding notional amount. WCEP Holdings LLC will pay its counterparty the equivalent of a 4% fixed interest payment on a predetermined notional value, and quarterly, WCEP Holdings LLC will receive the equivalent of a floating interest payment based on a three-month LIBOR calculated on the same notional value through May 31, 2023. All interest rate swap payments by WCEP Holdings LLC and its counterparties are made quarterly and the LIBOR is determined in advance of each interest period. Swaps became effective June 28, 2013, and amortize in proportion to the term loan. On October 21, 2014, WCEP Holdings LLC amended the credit agreement to reduce the related interest rate to LIBOR plus 3% . The proceeds of the distribution from Walnut Creek were utilized to make an optional repayment of $6 million on the term loan. In addition WCEP Holdings LLC partially terminated the interest rate agreements so that at least 90% and no more than 100% of the aggregate principal amount of the loans then outstanding will be subject to interest rate agreements. As of June 30, 2015 , $46 million was outstanding under the term loan. Avenal Solar Holdings LLC On March 18, 2015, Avenal Solar Holdings LLC, one of the Company's equity method investments, amended its credit agreement to increase its borrowings by $43 million and to reduce the related interest rate from 6 month LIBOR plus an applicable margin of 2.25% to 6 month LIBOR plus 1.75% from March 18, 2015 through March 17, 2022 and 6 month LIBOR plus 2.00% from March 18, 2022 through March 17, 2027 and 6 month LIBOR plus 2.25% from March 18, 2027 through the maturity date. As a result of the credit agreement amendment, the Company received net proceeds of $20 million after fees from its 49.95% ownership in Avenal. NRG West Holdings LLC On May 29, 2015, NRG West Holdings LLC amended its financing agreement to increase borrowings under the Tranche A facility by $5 million and to reduce the related interest rate to LIBOR plus an applicable margin of 1.625% from May 29, 2015 to August 31, 2017, LIBOR plus an applicable margin of 1.75% from September 1, 2017, to August 31, 2020, and LIBOR plus 1.875% from September 1, 2020 through the maturity date; to reduce the Tranche B loan interest rate to LIBOR plus an applicable margin of 2.250% from May 29, 2015, to August 31, 2017, LIBOR plus 2.375% from September 1, 2017, to August 31, 2020, and LIBOR plus an applicable margin of 2.50% from September 1, 2020 through the maturity date and to reduce the working capital facility by $9 million . The proceeds of the increased borrowing were used to pay costs associated with the refinancing. Further, the amendment resulted in a $7 million loss on debt extinguishment.

Segment Reporting

Segment Reporting	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Segment Reporting	Note 9 — Segment Reporting The Company’s segment structure reflects how management currently operates and allocates resources. The Company's businesses are primarily segregated based on conventional power generation, renewable businesses which consist of solar and wind, and the thermal and chilled water business. The Corporate segment reflects the Company's corporate costs. The Company's chief operating decision maker evaluates the performance of its segments based on operational measures including adjusted earnings before interest, depreciation and amortization, or Adjusted EBITDA, and cash available for distribution, or CAFD, as well as net income (loss). Three months ended June 30, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 85 $ 90 $ 42 $ — $ 217 Cost of operations 15 21 31 — 67 Depreciation and amortization 21 34 4 — 59 General and administrative — affiliate — — — 3 3 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 49 35 7 (4 ) 87 Equity in earnings of unconsolidated affiliates 4 5 — — 9 Loss on debt extinguishment (7 ) — — — (7 ) Interest expense (13 ) (16 ) (2 ) (11 ) (42 ) Net Income (Loss) $ 33 $ 24 $ 5 $ (15 ) $ 47 Total Assets $ 2,153 $ 4,223 $ 434 $ 234 $ 7,044 Three months ended June 30, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 87 $ 43 $ 43 $ — $ 173 Cost of operations 16 7 30 — 53 Depreciation and amortization 34 15 5 — 54 General and administrative — affiliate — — — 2 2 Operating income (loss) 37 21 8 (2 ) 64 Equity in earnings of unconsolidated affiliates 4 10 — — 14 Interest expense (15 ) (11 ) (2 ) (5 ) (33 ) Net Income (Loss) $ 26 $ 20 $ 6 $ (7 ) $ 45 Six months ended June 30, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 161 $ 147 $ 89 $ — $ 397 Cost of operations 36 41 65 — 142 Depreciation and amortization 42 62 9 — 113 General and administrative — affiliate — — — 6 6 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 83 44 15 (7 ) 135 Equity in earnings of unconsolidated affiliates 7 3 — — 10 Other income, net 1 — — — 1 Loss on debt extinguishment (7 ) — — — (7 ) Interest expense (25 ) (59 ) (4 ) (23 ) (111 ) Net Income (Loss) $ 59 $ (12 ) $ 11 $ (30 ) $ 28 Six months ended June 30, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 143 $ 62 $ 108 $ — $ 313 Cost of operations 26 11 76 — 113 Depreciation and amortization 47 22 9 — 78 General and administrative — affiliate — — — 4 4 Operating income (loss) 70 29 23 (4 ) 118 Equity in earnings of unconsolidated affiliates 7 8 — — 15 Other income, net — 1 — — 1 Interest expense (26 ) (23 ) (4 ) (6 ) (59 ) Net Income (Loss) $ 51 $ 15 $ 19 $ (10 ) $ 75

Related Party Transactions

Related Party Transactions	6 Months Ended
	Jun. 30, 2015
Related Party Transactions [Abstract]
Related Party Transactions Disclosure	Note 10 — Related Party Transactions Management Services Agreement by and between NRG and the Company NRG provides the Company with various operation, management, and administrative services, which include human resources, accounting, tax, legal, information systems, treasury, and risk management, as set forth in the Management Services Agreement. As of June 30, 2015 , the base management fee was approximately $7 million per year, subject to an inflation-based adjustment annually at an inflation factor based on the year-over-year U.S. consumer price index. The fee is also subject to adjustments following the consummation of future acquisitions and as a result of a change in the scope of services provided under the Management Services Agreement. During the six months ended June 30, 2015 , the fee was increased by approximately $1 million per year in connection with the acquisition of the January 2015 Drop Down Assets. Costs incurred under this agreement were $6 million and $4 million for the six months ended June 30, 2015 , and 2014 , respectively, which included certain direct expenses incurred by NRG on behalf of the Company in addition to the base management fee. There was a balance of $3 million due to NRG in accounts payable — affiliate as of June 30, 2015 . Operation and Maintenance Services (O&M) Agreements by and between NRG and Thermal Entities On October 1, 2014, NRG entered into Plant O&M Services Agreements with certain wholly-owned subsidiaries of the Company. NRG provides necessary and appropriate services to operate and maintain the subsidiaries' plant operations, businesses and thermal facilities. NRG is to be reimbursed for the provided services, as well as for all reasonable and related expenses and expenditures, and payments to third parties for services and materials rendered to or on behalf of the parties to the agreements. NRG is not entitled to any management fee or mark-up under the agreements. Prior to October 1, 2014, NRG provided the same services to the Thermal Business on an informal basis. Total fees incurred under the agreements were $15 million and $14 million for the six months ended June 30, 2015 , and 2014 , respectively. There was a balance of $28 million and $22 million due to NRG in accounts payable — affiliate as of June 30, 2015 , and December 31, 2014 , respectively. Administrative Services Agreement by and between Marsh Landing and GenOn Energy Services, LLC Marsh Landing is a party to an administrative services agreement with GenOn Energy Services, LLC, a wholly owned subsidiary of NRG, which provides invoice processing and payment on behalf of Marsh Landing. Marsh Landing reimburses GenOn Energy Services, LLC for the amounts paid by it. The Company reimbursed costs under this agreement of approximately $9 million for the six months ended June 30, 2015 , and 2014 . There was a balance of $0 million and $4 million due to GenOn Energy Services, LLC in accounts payable — affiliate as of June 30, 2015 , and December 31, 2014 , respectively. O&M Services Agreements by and between NRG and GenConn GenConn incurs fees under two O&M agreements with wholly-owned subsidiaries of NRG. The fees incurred under the agreements were $2 million and $3 million for the six months ended June 30, 2015 , and 2014 , respectively.

Condensed Consolidating Financi

Condensed Consolidating Financial Information Condensed Consolidating Financial Information	6 Months Ended
	Jun. 30, 2015
Condensed Consolidating Financial Information Disclosure [Abstract]
Condensed Financial Statements [Text Block]	Note 11 — Condensed Consolidating Financial Information As of June 30, 2015, Yield Operating LLC had outstanding $500 million of Senior Notes as shown in Note 8 , Long-term Debt . These Senior Notes are guaranteed by the Company, as well as certain of the Company's subsidiaries, or guarantor subsidiaries. These guarantees are both joint and several. The non-guarantor subsidiaries include the rest of the Company's subsidiaries, including the ones that are subject to project financing. Unless otherwise noted below, each of the following guarantor subsidiaries fully and unconditionally guaranteed the Senior Notes as of June 30, 2015 : NRG Yield LLC Alta Wind 1-5 Holding Company, LLC Alta Wind Company, LLC NRG Energy Center Omaha Holdings LLC NRG Energy Center Omaha LLC NYLD Fuel Cell Holdings LLC UB Fuel Cell, LLC NRG South Trent Holdings LLC NRG Yield DGPV Holding LLC NRG Yield RPV Holding LLC Yield Operating LLC conducts much of its business through and derives much of its income from its subsidiaries. Therefore, its ability to make required payments with respect to its indebtedness and other obligations depends on the financial results and condition of its subsidiaries and Yield Operating LLC's ability to receive funds from its subsidiaries. There are no restrictions on the ability of any of the guarantor subsidiaries to transfer funds to Yield Operating LLC. However, there may be restrictions for certain non-guarantor subsidiaries. The following condensed consolidating financial information presents the financial information of Yield LLC, Yield Operating LLC, the issuer of the Senior Notes, the guarantor subsidiaries and the non-guarantor subsidiaries in accordance with Rule 3-10 under the SEC Regulation S-X. The financial information may not necessarily be indicative of results of operations or financial position had the guarantor subsidiaries or non-guarantor subsidiaries operated as independent entities. In this presentation, Yield LLC consists of parent company operations. Guarantor subsidiaries and non-guarantor subsidiaries of Yield LLC are reported on an equity basis. For companies acquired, the fair values of the assets and liabilities acquired have been presented on a push-down accounting basis. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues (losses) $ — $ 5 $ 213 $ (1 ) $ — $ 217 Operating Costs and Expenses Cost of operations — 3 64 — — 67 Depreciation and amortization — 1 58 — — 59 General and administrative — affiliate — — — 3 — 3 Acquisition-related transaction and integration costs — — — 1 — 1 Total operating costs and expenses — 4 122 4 — 130 Operating Income (Loss) — 1 91 (5 ) — 87 Other Income (Expense) Equity in earnings of consolidated affiliates 40 6 — 59 (105 ) — Equity in earnings of unconsolidated affiliates — — — 9 — 9 Loss on debt extinguishment — — (7 ) — — (7 ) Interest expense — — (30 ) (12 ) — (42 ) Total other income (expense), net 40 6 (37 ) 56 (105 ) (40 ) Net Income 40 7 54 51 (105 ) 47 Less: Net (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Net Income Attributable to $ 40 $ 7 $ 58 $ 40 $ (105 ) $ 40 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Six Months Ended June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 10 $ 379 $ 8 $ — $ 397 Operating Costs and Expenses Cost of operations — 7 135 — — 142 Depreciation and amortization — 2 111 — — 113 General and administrative — affiliate — — — 6 — 6 Acquisition-related transaction and integration costs — — — 1 — 1 Total operating costs and expenses — 9 246 7 — 262 Operating Income — 1 133 1 — 135 Other Income (Expense) Equity in earnings (losses) of consolidated affiliates 21 (19 ) — 45 (47 ) — Equity in earnings of unconsolidated affiliates — — — 10 — 10 Other income, net — — 1 — — 1 Loss on debt extinguishment — — (7 ) — — (7 ) Interest expense — — (87 ) (24 ) — (111 ) Total other income (expense), net 21 (19 ) (93 ) 31 (47 ) (107 ) Net Income (Loss) 21 (18 ) 40 32 (47 ) 28 Less: Net (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Net Income (Loss) Attributable to $ 21 $ (18 ) $ 44 $ 21 $ (47 ) $ 21 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS) For the Three Months Ended June 30, 2015 NRG Yield LLC Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 40 $ 7 $ 54 $ 51 $ (105 ) $ 47 Other Comprehensive Income Unrealized gain on derivatives 25 1 24 25 (50 ) 25 Other comprehensive income 25 1 24 25 (50 ) 25 Comprehensive Income 65 8 78 76 (155 ) 72 Less: Comprehensive (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Comprehensive Income Attributable to NRG Yield LLC $ 65 $ 8 $ 82 $ 65 $ (155 ) $ 65 (a) All significant intercompany transactions have been eliminated in consolidation. For the Six Months Ended June 30, 2015 NRG Yield LLC Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income (Loss) $ 21 $ (18 ) $ 40 $ 32 $ (47 ) $ 28 Comprehensive Income (Loss) 21 (18 ) 40 32 (47 ) 28 Less: Comprehensive (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Comprehensive Income (Loss) Attributable to NRG Yield LLC $ 21 $ (18 ) $ 44 $ 21 $ (47 ) $ 21 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated ASSETS (In millions) Current Assets Cash and cash equivalents $ 220 $ — $ 61 $ — $ — $ 281 Restricted cash — — 38 — — 38 Accounts receivable — trade — 2 96 — — 98 Accounts receivable — affiliate — 23 65 158 (244 ) 2 Inventory — 2 27 — — 29 Derivative instruments — — — 4 — 4 Notes receivable — — 7 — — 7 Prepayments and other current assets — 1 18 — — 19 Total current assets 220 28 312 162 (244 ) 478 Net property, plant and equipment — 63 4,415 — — 4,478 Other Assets Investment in consolidated subsidiaries 1,946 574 — 2,692 (5,212 ) — Equity investments in affiliates — 18 — 531 — 549 Notes receivable — — 13 — — 13 Intangible assets, net — 57 1,332 — — 1,389 Derivative instruments — — 4 — — 4 Other non-current assets — — 124 9 — 133 Total other assets 1,946 649 1,473 3,232 (5,212 ) 2,088 Total Assets $ 2,166 $ 740 $ 6,200 $ 3,394 $ (5,456 ) $ 7,044 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Continued) June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC Eliminations (a) Consolidated LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 217 $ 190 $ — $ 407 Accounts payable — 1 22 — — 23 Accounts payable — affiliate 150 10 99 45 (244 ) 60 Derivative instruments — — 42 1 — 43 Accrued expenses and other current liabilities — 2 18 17 — 37 Total current liabilities 150 13 398 253 (244 ) 570 Other Liabilities Long-term debt — external — — 3,167 577 — 3,744 Long-term debt — affiliate — — — 618 — 618 Derivative instruments — — 44 — — 44 Other non-current liabilities — 1 51 — — 52 Total non-current liabilities — 1 3,262 1,195 — 4,458 Total Liabilities 150 14 3,660 1,448 (244 ) 5,028 Commitments and Contingencies Members' Equity Contributed capital 1,729 780 2,414 1,694 (4,888 ) 1,729 Retained earnings (accumulated deficit) 145 (51 ) 97 110 (156 ) 145 Noncontrolling interest 200 — 70 200 (270 ) 200 Accumulated other comprehensive loss (58 ) (3 ) (41 ) (58 ) 102 (58 ) Total Members' Equity 2,016 726 2,540 1,946 (5,212 ) 2,016 Total Liabilities and Members’ Equity $ 2,166 $ 740 $ 6,200 $ 3,394 $ (5,456 ) $ 7,044 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Six Months Ended June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Consolidated (In millions) Net Cash (Used in) Provided by Operating Activities $ (23 ) $ 10 $ 69 $ 32 $ 88 Cash Flows from Investing Activities Intercompany transactions from Yield LLC to subsidiaries (517 ) — — 517 — Acquisition of business, net of cash acquired — — — (37 ) (37 ) Acquisition of Drop Down Assets, net of cash acquired — — — (489 ) (489 ) Capital expenditures — — (8 ) — (8 ) Decrease in restricted cash — — 7 — 7 Decrease in notes receivable — — 3 — 3 Investments in unconsolidated affiliates — (4 ) — (309 ) (313 ) Net Cash (Used in) Provided by Investing Activities (517 ) (4 ) 2 (318 ) (837 ) Cash Flows from Financing Activities Transfer of funds under intercompany cash management arrangement (107 ) (6 ) — 113 — Investments in consolidated subsidiaries (contributions from parent) — — 491 (491 ) — Contributions from noncontrolling interests — — — 119 119 Proceeds from the issuance of Class C units 600 — — — 600 Payment of distributions (61 ) — — — (61 ) Proceeds from issuance of long-term debt — external — — 5 282 287 Proceeds from issuance of long-term debt — affiliate — — — 281 281 Payment of debt issuance costs — — (4 ) — (4 ) Payments for long-term debt — external — — (580 ) (18 ) (598 ) Net Cash Provided by (Used in) Financing Activities 432 (6 ) (88 ) 286 624 Net Decrease in Cash and Cash Equivalents (108 ) — (17 ) — (125 ) Cash and Cash Equivalents at Beginning of Period 328 — 78 — 406 Cash and Cash Equivalents at End of Period $ 220 $ — $ 61 $ — $ 281 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 5 $ 168 $ — $ — $ 173 Operating Costs and Expenses Cost of operations — 3 50 — — 53 Depreciation and amortization — 1 53 — — 54 General and administrative — affiliate — — — 2 — 2 Total operating costs and expenses — 4 103 2 — 109 Operating Income (Loss) — 1 65 (2 ) — 64 Other Income (Expense) Equity in earnings of consolidated affiliates 45 2 — 38 (85 ) — Equity in earnings of unconsolidated affiliates — — — 14 — 14 Interest expense — — (28 ) (5 ) — (33 ) Total other income (expense), net 45 2 (28 ) 47 (85 ) (19 ) Net Income $ 45 $ 3 $ 37 $ 45 $ (85 ) $ 45 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Six Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 12 $ 301 $ — $ — $ 313 Operating Costs and Expenses Cost of operations 8 105 — — 113 Depreciation and amortization 2 76 — — 78 General and administrative — affiliate — — — 4 — 4 Total operating costs and expenses — 10 181 4 — 195 Operating Income (Loss) — 2 120 (4 ) — 118 Other Income (Expense) Equity in earnings of consolidated affiliates 75 2 — 70 (147 ) — Equity in earnings of unconsolidated affiliates — — — 15 — 15 Other income, net — — 1 — — 1 Interest expense — — (53 ) (6 ) — (59 ) Total other income (expense), net 75 2 (52 ) 79 (147 ) (43 ) Net Income $ 75 $ 4 $ 68 $ 75 $ (147 ) $ 75 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME For the Three Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 45 $ 3 $ 37 $ 45 $ (85 ) $ 45 Other Comprehensive Loss Unrealized loss on derivatives (22 ) — (21 ) (22 ) 43 (22 ) Other comprehensive loss (22 ) — (21 ) (22 ) 43 (22 ) Comprehensive Income $ 23 $ 3 $ 16 $ 23 $ (42 ) $ 23 (a) All significant intercompany transactions have been eliminated in consolidation. For the Six Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 75 $ 4 $ 68 $ 75 $ (147 ) $ 75 Other Comprehensive Loss Unrealized loss on derivatives (34 ) — (32 ) (34 ) 66 (34 ) Other comprehensive loss (34 ) — (32 ) (34 ) 66 (34 ) Comprehensive Income $ 41 $ 4 $ 36 $ 41 $ (81 ) $ 41 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC Eliminations (a) Consolidated ASSETS (In millions) Current Assets Cash and cash equivalents $ 328 $ — $ 78 $ — $ — $ 406 Restricted cash — — 45 — — 45 Accounts receivable — trade — 3 82 — — 85 Accounts receivable — affiliate (256 ) 17 66 268 (95 ) — Inventory — 1 26 — — 27 Notes receivable — — 6 — — 6 Prepayments and other current assets — 1 20 — — 21 Total current assets 72 22 323 268 (95 ) 590 Net property, plant and equipment — 56 4,410 — — 4,466 Other Assets Investment in consolidated subsidiaries 1,664 585 — 2,045 (4,294 ) — Equity investments in affiliates — — — 227 — 227 Notes receivable — — 15 — — 15 Intangible assets, net — 58 1,365 — — 1,423 Derivative instruments — — 2 — — 2 Other non-current assets — — 93 10 — 103 Total other assets 1,664 643 1,475 2,282 (4,294 ) 1,770 Total Assets $ 1,736 $ 721 $ 6,208 $ 2,550 $ (4,389 ) $ 6,826 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Continued) December 31, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC Eliminations (a) Consolidated LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 214 $ — $ — $ 214 Accounts payable — 1 19 — — 20 Accounts payable — affiliate — 8 99 33 (95 ) 45 Derivative instruments — — 48 — — 48 Accrued expenses and other current liabilities — 2 43 16 — 61 Total current liabilities — 11 423 49 (95 ) 388 Other Liabilities Long-term debt — external — — 3,747 500 — 4,247 Long-term debt — affiliate — — — 337 — 337 Derivative instruments — — 69 — — 69 Other non-current liabilities — — 49 — — 49 Total non-current liabilities — — 3,865 837 — 4,702 Total Liabilities — 11 4,288 886 (95 ) 5,090 Commitments and Contingencies Members' Equity Contributed capital 1,609 747 1,848 1,542 (4,137 ) 1,609 Retained earnings (Accumulated deficit) 185 (34 ) 113 180 (259 ) 185 Accumulated other comprehensive loss (58 ) (3 ) (41 ) (58 ) 102 (58 ) Total Members' Equity 1,736 710 1,920 1,664 (4,294 ) 1,736 Total Liabilities and Members’ Equity $ 1,736 $ 721 $ 6,208 $ 2,550 $ (4,389 ) $ 6,826 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Six Months Ended June 30, 2014 NRG Yield LLC Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Consolidated (In millions) Net Cash Provided by (Used in) Operating Activities $ 46 $ (33 ) $ 62 $ 75 Cash Flows from Investing Activities Acquisition of Drop Down Assets, net of cash acquired — 21 (357 ) (336 ) Capital expenditures — (29 ) — (29 ) Decrease in restricted cash — 49 — 49 Decrease in notes receivable — 3 2 5 Proceeds from renewable energy grants — 137 — 137 Investments in unconsolidated affiliates — — (15 ) (15 ) Other — 11 — 11 Net Cash Provided by (Used in) Investing Activities — 192 (370 ) (178 ) Cash Flows from Financing Activities Capital contributions from NRG — 2 — 2 Distributions and return of capital to NRG — (25 ) — (25 ) Payment of distributions (44 ) — — (44 ) Proceeds from issuance of long-term debt - external — 41 — 41 Transfer of funds under intercompany cash management arrangement 49 — (49 ) — Payments of long-term debt- external — (154 ) — (154 ) Proceeds from long-term debt - affiliate — — 337 337 Payment of debt issuance costs — (5 ) — (5 ) Net Cash Provided by (Used in) Financing Activities 5 (141 ) 288 152 Net Increase (Decrease) in Cash and Cash Equivalents 51 18 (20 ) 49 Cash and Cash Equivalents at Beginning of Period 3 36 20 59 Cash and Cash Equivalents at End of Period $ 54 $ 54 $ — $ 108 (a) All significant intercompany transactions have been eliminated in consolidation.

Summary of Significant Accoun18

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Policies)	6 Months Ended
	Jun. 30, 2015
Accounting Policies [Abstract]
Distributions [Policy Text Block]	Distributions On August 4, 2015 , NRG Yield LLC announced the declaration of a distribution on its Class A, Class B, Class C and Class D units of $0.21 per unit payable on September 15, 2015 to unit holders of record as of September 1, 2015 . On May 20, 2015, the Company declared a distribution on its Class A, Class B, Class C and Class D units of $0.20 per unit, which was paid on June 15, 2015. On February 17, 2015, the Company declared a distribution on its Class A and Class B units of $0.39 per unit, which was paid on March 16, 2015.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in accordance with U.S. GAAP requires management to make estimates and assumptions. These estimates and assumptions impact the reported amount of assets and liabilities and disclosures of contingent assets and liabilities as of the date of the consolidated financial statements. They also impact the reported amount of net earnings during the reporting period. Actual results could be different from these estimates.
Recent Accounting Developments	Recent Accounting Developments ASU 2015-03 — In April 2015, the FASB issued ASU No. 2015-03, Interest - Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs , or ASU No. 2015-03. The amendments of ASU No. 2015-03 were issued to reduce complexity in the balance sheet presentation of debt issuance costs. ASU No. 2015-03 requires that debt issuance costs be presented in the balance sheet as a direct deduction from the carrying amount of debt liability, consistent with debt discounts or premiums. The recognition and measurement guidance for debt issuance costs are not affected by the amendments in this standard. The guidance in ASU No. 2015-03 is effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. Early adoption is permitted for financial statements that have not been previously issued. Had the Company adopted this guidance early, other assets would have been lower by $ 55 million and $ 61 million with corresponding decreases in debt as of June 30, 2015, and December 31, 2014, respectively. The adoption of this standard will have no impact on the Company's results of operations, cash flows or net assets. ASU 2015-02 — In February 2015, the FASB issued ASU No. 2015-02, Consolidation (Topic 810): Amendments to the Consolidation Analysis , or ASU No. 2015-02. The amendments of ASU No. 2015-02 were issued in an effort to minimize situations under previously existing guidance in which a reporting entity was required to consolidate another legal entity in which that reporting entity did not have: (1) the ability through contractual rights to act primarily on its own behalf; (2) ownership of the majority of the legal entity's voting rights; or (3) the exposure to a majority of the legal entity's economic benefits. ASU No. 2015-02 affects reporting entities that are required to evaluate whether they should consolidate certain legal entities. All legal entities are subject to reevaluation under the revised consolidation model. The guidance in ASU No. 2015-02 is effective for periods beginning after December 15, 2015. Early adoption is permitted. The Company adopted the standard effective January 1, 2015 and the adoption of this standard did not impact the Company's results of operations, cash flows or financial position. ASU 2014-16 — In November 2014, the FASB issued ASU No. 2014-16, Derivatives and Hedging (Topic 815): Determining Whether the Host Contract in a Hybrid Financial Instrument Issued in the Form of a Share Is More Akin to Debt or to Equity , or ASU No. 2014-16. The amendments of ASU No. 2014-16 clarify how U.S. GAAP should be applied in determining whether the nature of a host contract is more akin to debt or equity and in evaluating whether the economic characteristics and risks of an embedded feature are "clearly and closely related" to its host contract. The guidance in ASU No. 2014-16 is effective for fiscal years, and interim periods within those fiscal years, beginning after December 15, 2015. Early adoption is permitted. The Company adopted the standard effective January 1, 2015 and the adoption of this standard did not impact the Company's results of operations, cash flows or financial position. ASU 2014-09 — In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606) , or ASU No. 2014-09. The amendments of ASU No. 2014-09 complete the joint effort between the FASB and the International Accounting Standards Board, or IASB, to develop a common revenue standard for U.S. GAAP and International Financial Reporting Standards, or IFRS, and to improve financial reporting. The guidance in ASU No. 2014-09 provides that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for the goods or services provided and establishes the following steps to be applied by an entity: (1) identify the contract with a customer; (2) identify the performance obligations in the contract; (3) determine the transaction price; (4) allocate the transaction price to the performance obligations in the contract; and (5) recognize revenue when (or as) the entity satisfies the performance obligation. On July 9, 2015, the FASB voted to defer the effective date by one year to make the guidance of ASU No. 2014-09 effective for annual reporting periods beginning after December 15, 2017, including interim periods therein. Early adoption is permitted, but not prior to the original effective date, which was for annual reporting periods beginning after December 15, 2016. The Company is currently evaluating the impact of the standard on the Company's results of operations, cash flows and financial position.

Segment Reporting Segment Repor

Segment Reporting Segment Reporting (Policies)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Segment Reporting, Policy [Policy Text Block]	The Company’s segment structure reflects how management currently operates and allocates resources. The Company's businesses are primarily segregated based on conventional power generation, renewable businesses which consist of solar and wind, and the thermal and chilled water business. The Corporate segment reflects the Company's corporate costs. The Company's chief operating decision maker evaluates the performance of its segments based on operational measures including adjusted earnings before interest, depreciation and amortization, or Adjusted EBITDA, and cash available for distribution, or CAFD, as well as net income (loss).

Summary of Significant Accoun20

Summary of Significant Accounting Policies Noncontrolling Interest Disclosure (Tables)	6 Months Ended
	Jun. 30, 2015
Noncontrolling Interest [Abstract]
Noncontrolling Interest Disclosure [Text Block]	The following table reflects the changes in the Company's noncontrolling interest balance: (In millions) Balance as of December 31, 2014 — Contributions from noncontrolling interest for Alta Wind X-X1 TE Holdco 119 Noncontrolling interest acquired in Spring Canyon acquisition 74 Comprehensive income 7 Balance as of June 30, 2015 $ 200

Business Acquisitions Business

Business Acquisitions Business Acquisitions (Tables)	6 Months Ended
	Jun. 30, 2015
Business Acquisition
Business Acquisition, Purchase Price [Table Text Block]	The purchase price of $923 million was provisionally allocated as follows: Acquisition Date Fair Value at December 31, 2014 Measurement period adjustments Revised Acquisition Date (In millions) Assets Cash $ 22 $ — $ 22 Current and non-current assets 49 (2 ) 47 Property, plant and equipment 1,304 6 1,310 Intangible assets 1,177 (6 ) 1,171 Total assets acquired 2,552 (2 ) 2,550 Liabilities Debt 1,591 — 1,591 Current and non-current liabilities 38 (2 ) 36 Total liabilities assumed 1,629 (2 ) 1,627 Net assets acquired $ 923 $ — $ 923
Business Acquisition, Pro Forma Information [Table Text Block]	The following unaudited supplemental pro forma information represents the results of operations as if the Company had acquired the January 2015 Drop Down Assets on January 1, 2014, including the impact of acquisition accounting with respect to NRG's acquisition of the projects. For the six months ended (In millions) June 30, 2014 Operating revenues $ 339 Net income 71
EME-NYLD Assets [Member]
Business Acquisition
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	6 Months Ended
	Jun. 30, 2015
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	The Company’s major classes of property, plant, and equipment were as follows: June 30, 2015 December 31, 2014 Depreciable Lives (In millions) Facilities and equipment $ 4,832 $ 4,709 2 - 40 Years Land and improvements 87 87 Construction in progress 8 8 Total property, plant and equipment 4,927 4,804 Accumulated depreciation (449 ) (338 ) Net property, plant and equipment $ 4,478 $ 4,466

Investments Accounted for by 23

Investments Accounted for by the Equity Method and Variable Interest Entities (Tables)	6 Months Ended
	Jun. 30, 2015
GCE Holdings LLC
Schedule of Equity Method Investments
Summarized financial information of equity method investment	The following table presents summarized financial information for GCE Holding LLC: Three months ended June 30, Six months ended June 30, (in millions) 2015 2014 2015 2014 Income Statement Data: Operating revenues $ 18 $ 18 $ 40 $ 44 Operating income 11 10 20 20 Net income $ 8 $ 7 $ 14 $ 14 June 30, 2015 December 31, 2014 Balance Sheet Data: (In millions) Current assets $ 37 $ 33 Non-current assets 424 438 Current liabilities 16 20 Non-current liabilities $ 219 $ 223

Fair Value of Financial Instr24

Fair Value of Financial Instruments (Tables)	6 Months Ended
	Jun. 30, 2015
Fair Value Disclosures [Abstract]
Estimated carrying values and fair values of the Company's recorded financial instruments	The estimated carrying amounts and fair values of the Company’s recorded financial instruments not carried at fair market value are as follows: As of June 30, 2015 As of December 31, 2014 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Assets: Notes receivable, including current portion $ 20 $ 20 $ 21 $ 21 Liabilities: Long-term debt — affiliate 618 643 337 386 Long-term debt, including current portion — external $ 4,151 $ 4,155 $ 4,461 $ 4,478
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The Company records its derivative assets and liabilities at fair market value on its consolidated balance sheet. The following table presents assets and liabilities measured and recorded at fair value on the Company's consolidated balance sheets on a recurring basis and their level within the fair value hierarchy: As of June 30, 2015 As of December 31, 2014 Fair Value (a) Fair Value (a) (In millions) Level 2 Level 2 Derivative assets: Commodity contracts $ 4 $ — Interest rate contracts 4 2 Total assets 8 2 Derivative liabilities: Commodity contracts 3 3 Interest rate contracts 84 114 Total liabilities $ 87 $ 117 (a) There were no assets or liabilities classified as Level 1 or Level 3 as of June 30, 2015 , or December 31, 2014 .

Accounting for Derivative Ins25

Accounting for Derivative Instruments and Hedging Activities (Tables)	6 Months Ended
	Jun. 30, 2015
Accounting for Derivative Instruments and Hedging Activities Disclosure [Abstract]
Net notional volume buy/(sell) of NRG Yield's open derivative transactions broken out by commodity	The following table summarizes the net notional volume buy/(sell) of the Company's open derivative transactions broken out by commodity as of June 30, 2015 , and December 31, 2014 . Total Volume June 30, 2015 December 31, 2014 Commodity Units (In millions) Natural Gas MMBtu 3 2 Interest Dollars $ 1,841 $ 2,817
Fair value within the derivative instrument valuation on the balance sheets	The following table summarizes the fair value within the derivative instrument valuation on the balance sheet: Fair Value Derivative Assets Derivative Liabilities June 30, 2015 December 31, 2014 June 30, 2015 December 31, 2014 (In millions) Derivatives Designated as Cash Flow Hedges: Interest rate contracts current $ — $ — $ 37 $ 40 Interest rate contracts long-term 4 2 42 49 Total Derivatives Designated as Cash Flow Hedges 4 2 79 89 Derivatives Not Designated as Cash Flow Hedges : Interest rate contracts current — — 3 5 Interest rate contracts long-term — — 2 20 Commodity contracts current 4 — 3 3 Total Derivatives Not Designated as Cash Flow Hedges 4 — 8 28 Total Derivatives $ 8 $ 2 $ 87 $ 117
Offsetting of derivatives by counterparty master agreement level and collateral received or paid	The Company has elected to present derivative assets and liabilities on the balance sheet on a trade-by-trade basis and does not offset amounts at the counterparty master agreement level. As of June 30, 2015 , there was no outstanding collateral paid or received. The following table summarizes the offsetting of derivatives by counterparty master agreement level: Gross Amounts Not Offset in the Statement of Financial Position As of June 30, 2015 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ 4 $ (1 ) $ 3 Derivative liabilities (3 ) 1 (2 ) Total commodity contracts 1 — 1 Interest rate contracts: Derivative assets 4 (3 ) 1 Derivative liabilities (84 ) 3 (81 ) Total interest rate contracts (80 ) — (80 ) Total derivative instruments $ (79 ) $ — $ (79 ) Gross Amounts Not Offset in the Statement of Financial Position As of December 31, 2014 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ — $ — $ — Derivative liabilities (3 ) — (3 ) Total commodity contracts (3 ) — (3 ) Interest rate contracts: Derivative assets 2 (2 ) — Derivative liabilities (114 ) 2 (112 ) Total interest rate contracts (112 ) — (112 ) Total derivative instruments $ (115 ) $ — $ (115 )
Effects of NRG Yield's accumulated OCI balance attributable to interest rate swaps designated as cash flow hedge derivatives, net of tax	The following table summarizes the effects on the Company’s accumulated OCL, balance attributable to interest rate swaps designated as cash flow hedge derivatives: Three months ended June 30, Six months ended June 30, 2015 2014 2015 2014 (In millions) Accumulated OCL beginning balance $ (83 ) $ (13 ) $ (58 ) $ (1 ) Reclassified from accumulated OCL to income due to realization of previously deferred amounts 4 4 7 7 Mark-to-market of cash flow hedge accounting contracts 21 (26 ) (7 ) (41 ) Accumulated OCL ending balance $ (58 ) $ (35 ) $ (58 ) $ (35 ) Losses expected to be realized from OCL during the next 12 months $ (17 ) $ (17 )

Long-term Debt (Tables)

Long-term Debt (Tables)	6 Months Ended
	Jun. 30, 2015
Debt Disclosure [Abstract]
Schedule of long-term debt	This footnote should be read in conjunction with the complete description under Note 9, Long-term Debt, to the Company's financial statements for the year ended December 31, 2014 included in the Company's Prospectus dated June 22, 2015. Long-term debt consisted of the following: June 30, 2015 December 31, 2014 June 30, 2015, interest rate % (a) (In millions, except rates) Senior Notes, due 2024 $ 500 $ 500 5.375 Long-term debt - affiliate, due 2019 337 337 3.580 Long-term debt - affiliate, due 2020 281 — 3.325 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 267 — L+2.50 Project-level debt: Alta Wind I, lease financing arrangement, due 2034 255 261 7.015 Alta Wind II, lease financing arrangement, due 2034 200 205 5.696 Alta Wind III, lease financing arrangement, due 2034 208 212 6.067 Alta Wind IV, lease financing arrangement, due 2034 138 138 5.938 Alta Wind V, lease financing arrangement, due 2035 215 220 6.071 Alta Wind X, due 2021 — 300 L+2.00 Alta Wind XI, due 2021 — 191 L+2.00 Alta Realty Investments, due 2031 33 34 7.00 Alta Wind Asset Management, due 2031 19 20 L+2.375 NRG West Holdings LLC, due 2023 (El Segundo Energy Center) 489 506 L+1.625 - L+2.25 NRG Marsh Landing LLC, due 2017 and 2023 454 464 L+1.75 - L+1.875 Walnut Creek Energy, due 2023 381 391 L+1.625 Tapestry Wind LLC, due 2021 185 192 L+1.625 NRG Solar Alpine LLC, due 2014 and 2022 161 163 L+1.75 NRG Energy Center Minneapolis LLC, due 2017 and 2025 112 121 5.95 -7.25 Laredo Ridge LLC, due 2026 106 108 L+1.875 NRG Solar Borrego LLC, due 2025 and 2038 74 75 L+ 2.50/5.65 South Trent Wind LLC, due 2020 63 65 L+2.75 NRG Solar Avra Valley LLC, due 2031 62 63 L+1.75 TA High Desert LLC, due 2020 and 2032 54 55 L+2.50/5.15 WCEP Holdings LLC, due 2023 46 46 L+3.00 NRG Roadrunner LLC, due 2031 41 42 L+2.01 NRG Solar Kansas South LLC, due 2031 34 35 L+2.00 NRG Solar Blythe LLC, due 2028 22 22 L+2.75 PFMG and related subsidiaries financing agreement, due 2030 31 31 6.00 NRG Energy Center Princeton LLC, due 2017 1 1 5.95 Subtotal project-level debt: 3,384 3,961 Total debt 4,769 4,798 Less current maturities 407 214 Total long-term debt $ 4,362 $ 4,584 (a) As of June 30, 2015 , L+ equals 3 month LIBOR plus x%, except for the NRG Marsh Landing term loan, Walnut Creek term loan, and the Revolving Credit Facility where L+ equals 1 month LIBOR plus x% and Kansas South where L+ equals 6 month LIBOR plus x%.

Segment Reporting (Tables)

Segment Reporting (Tables)	6 Months Ended
	Jun. 30, 2015
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Three months ended June 30, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 85 $ 90 $ 42 $ — $ 217 Cost of operations 15 21 31 — 67 Depreciation and amortization 21 34 4 — 59 General and administrative — affiliate — — — 3 3 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 49 35 7 (4 ) 87 Equity in earnings of unconsolidated affiliates 4 5 — — 9 Loss on debt extinguishment (7 ) — — — (7 ) Interest expense (13 ) (16 ) (2 ) (11 ) (42 ) Net Income (Loss) $ 33 $ 24 $ 5 $ (15 ) $ 47 Total Assets $ 2,153 $ 4,223 $ 434 $ 234 $ 7,044 Three months ended June 30, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 87 $ 43 $ 43 $ — $ 173 Cost of operations 16 7 30 — 53 Depreciation and amortization 34 15 5 — 54 General and administrative — affiliate — — — 2 2 Operating income (loss) 37 21 8 (2 ) 64 Equity in earnings of unconsolidated affiliates 4 10 — — 14 Interest expense (15 ) (11 ) (2 ) (5 ) (33 ) Net Income (Loss) $ 26 $ 20 $ 6 $ (7 ) $ 45 Six months ended June 30, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 161 $ 147 $ 89 $ — $ 397 Cost of operations 36 41 65 — 142 Depreciation and amortization 42 62 9 — 113 General and administrative — affiliate — — — 6 6 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 83 44 15 (7 ) 135 Equity in earnings of unconsolidated affiliates 7 3 — — 10 Other income, net 1 — — — 1 Loss on debt extinguishment (7 ) — — — (7 ) Interest expense (25 ) (59 ) (4 ) (23 ) (111 ) Net Income (Loss) $ 59 $ (12 ) $ 11 $ (30 ) $ 28 Six months ended June 30, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 143 $ 62 $ 108 $ — $ 313 Cost of operations 26 11 76 — 113 Depreciation and amortization 47 22 9 — 78 General and administrative — affiliate — — — 4 4 Operating income (loss) 70 29 23 (4 ) 118 Equity in earnings of unconsolidated affiliates 7 8 — — 15 Other income, net — 1 — — 1 Interest expense (26 ) (23 ) (4 ) (6 ) (59 ) Net Income (Loss) $ 51 $ 15 $ 19 $ (10 ) $ 75

Condensed Consolidating Finan28

Condensed Consolidating Financial Information Condensed Consolidating Financial Information (Tables)	6 Months Ended
	Jun. 30, 2015
Condensed Consolidating Financial Information Disclosure [Abstract]
Condensed Cash Flow Statement [Table Text Block]	NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Six Months Ended June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Consolidated (In millions) Net Cash (Used in) Provided by Operating Activities $ (23 ) $ 10 $ 69 $ 32 $ 88 Cash Flows from Investing Activities Intercompany transactions from Yield LLC to subsidiaries (517 ) — — 517 — Acquisition of business, net of cash acquired — — — (37 ) (37 ) Acquisition of Drop Down Assets, net of cash acquired — — — (489 ) (489 ) Capital expenditures — — (8 ) — (8 ) Decrease in restricted cash — — 7 — 7 Decrease in notes receivable — — 3 — 3 Investments in unconsolidated affiliates — (4 ) — (309 ) (313 ) Net Cash (Used in) Provided by Investing Activities (517 ) (4 ) 2 (318 ) (837 ) Cash Flows from Financing Activities Transfer of funds under intercompany cash management arrangement (107 ) (6 ) — 113 — Investments in consolidated subsidiaries (contributions from parent) — — 491 (491 ) — Contributions from noncontrolling interests — — — 119 119 Proceeds from the issuance of Class C units 600 — — — 600 Payment of distributions (61 ) — — — (61 ) Proceeds from issuance of long-term debt — external — — 5 282 287 Proceeds from issuance of long-term debt — affiliate — — — 281 281 Payment of debt issuance costs — — (4 ) — (4 ) Payments for long-term debt — external — — (580 ) (18 ) (598 ) Net Cash Provided by (Used in) Financing Activities 432 (6 ) (88 ) 286 624 Net Decrease in Cash and Cash Equivalents (108 ) — (17 ) — (125 ) Cash and Cash Equivalents at Beginning of Period 328 — 78 — 406 Cash and Cash Equivalents at End of Period $ 220 $ — $ 61 $ — $ 281 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Six Months Ended June 30, 2014 NRG Yield LLC Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Consolidated (In millions) Net Cash Provided by (Used in) Operating Activities $ 46 $ (33 ) $ 62 $ 75 Cash Flows from Investing Activities Acquisition of Drop Down Assets, net of cash acquired — 21 (357 ) (336 ) Capital expenditures — (29 ) — (29 ) Decrease in restricted cash — 49 — 49 Decrease in notes receivable — 3 2 5 Proceeds from renewable energy grants — 137 — 137 Investments in unconsolidated affiliates — — (15 ) (15 ) Other — 11 — 11 Net Cash Provided by (Used in) Investing Activities — 192 (370 ) (178 ) Cash Flows from Financing Activities Capital contributions from NRG — 2 — 2 Distributions and return of capital to NRG — (25 ) — (25 ) Payment of distributions (44 ) — — (44 ) Proceeds from issuance of long-term debt - external — 41 — 41 Transfer of funds under intercompany cash management arrangement 49 — (49 ) — Payments of long-term debt- external — (154 ) — (154 ) Proceeds from long-term debt - affiliate — — 337 337 Payment of debt issuance costs — (5 ) — (5 ) Net Cash Provided by (Used in) Financing Activities 5 (141 ) 288 152 Net Increase (Decrease) in Cash and Cash Equivalents 51 18 (20 ) 49 Cash and Cash Equivalents at Beginning of Period 3 36 20 59 Cash and Cash Equivalents at End of Period $ 54 $ 54 $ — $ 108 (a) All significant intercompany transactions have been eliminated in consolidation.
Condensed Balance Sheet [Table Text Block]	NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated ASSETS (In millions) Current Assets Cash and cash equivalents $ 220 $ — $ 61 $ — $ — $ 281 Restricted cash — — 38 — — 38 Accounts receivable — trade — 2 96 — — 98 Accounts receivable — affiliate — 23 65 158 (244 ) 2 Inventory — 2 27 — — 29 Derivative instruments — — — 4 — 4 Notes receivable — — 7 — — 7 Prepayments and other current assets — 1 18 — — 19 Total current assets 220 28 312 162 (244 ) 478 Net property, plant and equipment — 63 4,415 — — 4,478 Other Assets Investment in consolidated subsidiaries 1,946 574 — 2,692 (5,212 ) — Equity investments in affiliates — 18 — 531 — 549 Notes receivable — — 13 — — 13 Intangible assets, net — 57 1,332 — — 1,389 Derivative instruments — — 4 — — 4 Other non-current assets — — 124 9 — 133 Total other assets 1,946 649 1,473 3,232 (5,212 ) 2,088 Total Assets $ 2,166 $ 740 $ 6,200 $ 3,394 $ (5,456 ) $ 7,044 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Continued) June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC Eliminations (a) Consolidated LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 217 $ 190 $ — $ 407 Accounts payable — 1 22 — — 23 Accounts payable — affiliate 150 10 99 45 (244 ) 60 Derivative instruments — — 42 1 — 43 Accrued expenses and other current liabilities — 2 18 17 — 37 Total current liabilities 150 13 398 253 (244 ) 570 Other Liabilities Long-term debt — external — — 3,167 577 — 3,744 Long-term debt — affiliate — — — 618 — 618 Derivative instruments — — 44 — — 44 Other non-current liabilities — 1 51 — — 52 Total non-current liabilities — 1 3,262 1,195 — 4,458 Total Liabilities 150 14 3,660 1,448 (244 ) 5,028 Commitments and Contingencies Members' Equity Contributed capital 1,729 780 2,414 1,694 (4,888 ) 1,729 Retained earnings (accumulated deficit) 145 (51 ) 97 110 (156 ) 145 Noncontrolling interest 200 — 70 200 (270 ) 200 Accumulated other comprehensive loss (58 ) (3 ) (41 ) (58 ) 102 (58 ) Total Members' Equity 2,016 726 2,540 1,946 (5,212 ) 2,016 Total Liabilities and Members’ Equity $ 2,166 $ 740 $ 6,200 $ 3,394 $ (5,456 ) $ 7,044 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC Eliminations (a) Consolidated ASSETS (In millions) Current Assets Cash and cash equivalents $ 328 $ — $ 78 $ — $ — $ 406 Restricted cash — — 45 — — 45 Accounts receivable — trade — 3 82 — — 85 Accounts receivable — affiliate (256 ) 17 66 268 (95 ) — Inventory — 1 26 — — 27 Notes receivable — — 6 — — 6 Prepayments and other current assets — 1 20 — — 21 Total current assets 72 22 323 268 (95 ) 590 Net property, plant and equipment — 56 4,410 — — 4,466 Other Assets Investment in consolidated subsidiaries 1,664 585 — 2,045 (4,294 ) — Equity investments in affiliates — — — 227 — 227 Notes receivable — — 15 — — 15 Intangible assets, net — 58 1,365 — — 1,423 Derivative instruments — — 2 — — 2 Other non-current assets — — 93 10 — 103 Total other assets 1,664 643 1,475 2,282 (4,294 ) 1,770 Total Assets $ 1,736 $ 721 $ 6,208 $ 2,550 $ (4,389 ) $ 6,826 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS (Continued) December 31, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC Eliminations (a) Consolidated LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 214 $ — $ — $ 214 Accounts payable — 1 19 — — 20 Accounts payable — affiliate — 8 99 33 (95 ) 45 Derivative instruments — — 48 — — 48 Accrued expenses and other current liabilities — 2 43 16 — 61 Total current liabilities — 11 423 49 (95 ) 388 Other Liabilities Long-term debt — external — — 3,747 500 — 4,247 Long-term debt — affiliate — — — 337 — 337 Derivative instruments — — 69 — — 69 Other non-current liabilities — — 49 — — 49 Total non-current liabilities — — 3,865 837 — 4,702 Total Liabilities — 11 4,288 886 (95 ) 5,090 Commitments and Contingencies Members' Equity Contributed capital 1,609 747 1,848 1,542 (4,137 ) 1,609 Retained earnings (Accumulated deficit) 185 (34 ) 113 180 (259 ) 185 Accumulated other comprehensive loss (58 ) (3 ) (41 ) (58 ) 102 (58 ) Total Members' Equity 1,736 710 1,920 1,664 (4,294 ) 1,736 Total Liabilities and Members’ Equity $ 1,736 $ 721 $ 6,208 $ 2,550 $ (4,389 ) $ 6,826 (a) All significant intercompany transactions have been eliminated in consolidation.
Condensed Statement of Comprehensive Income [Table Text Block]	For the Three Months Ended June 30, 2015 NRG Yield LLC Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 40 $ 7 $ 54 $ 51 $ (105 ) $ 47 Other Comprehensive Income Unrealized gain on derivatives 25 1 24 25 (50 ) 25 Other comprehensive income 25 1 24 25 (50 ) 25 Comprehensive Income 65 8 78 76 (155 ) 72 Less: Comprehensive (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Comprehensive Income Attributable to NRG Yield LLC $ 65 $ 8 $ 82 $ 65 $ (155 ) $ 65 (a) All significant intercompany transactions have been eliminated in consolidation. For the Six Months Ended June 30, 2015 NRG Yield LLC Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income (Loss) $ 21 $ (18 ) $ 40 $ 32 $ (47 ) $ 28 Comprehensive Income (Loss) 21 (18 ) 40 32 (47 ) 28 Less: Comprehensive (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Comprehensive Income (Loss) Attributable to NRG Yield LLC $ 21 $ (18 ) $ 44 $ 21 $ (47 ) $ 21 (a) All significant intercompany transactions have been eliminated in consolidation. For the Three Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 45 $ 3 $ 37 $ 45 $ (85 ) $ 45 Other Comprehensive Loss Unrealized loss on derivatives (22 ) — (21 ) (22 ) 43 (22 ) Other comprehensive loss (22 ) — (21 ) (22 ) 43 (22 ) Comprehensive Income $ 23 $ 3 $ 16 $ 23 $ (42 ) $ 23 (a) All significant intercompany transactions have been eliminated in consolidation. For the Six Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 75 $ 4 $ 68 $ 75 $ (147 ) $ 75 Other Comprehensive Loss Unrealized loss on derivatives (34 ) — (32 ) (34 ) 66 (34 ) Other comprehensive loss (34 ) — (32 ) (34 ) 66 (34 ) Comprehensive Income $ 41 $ 4 $ 36 $ 41 $ (81 ) $ 41 (a) All significant intercompany transactions have been eliminated in consolidation.
Condensed Income Statement [Table Text Block]	NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues (losses) $ — $ 5 $ 213 $ (1 ) $ — $ 217 Operating Costs and Expenses Cost of operations — 3 64 — — 67 Depreciation and amortization — 1 58 — — 59 General and administrative — affiliate — — — 3 — 3 Acquisition-related transaction and integration costs — — — 1 — 1 Total operating costs and expenses — 4 122 4 — 130 Operating Income (Loss) — 1 91 (5 ) — 87 Other Income (Expense) Equity in earnings of consolidated affiliates 40 6 — 59 (105 ) — Equity in earnings of unconsolidated affiliates — — — 9 — 9 Loss on debt extinguishment — — (7 ) — — (7 ) Interest expense — — (30 ) (12 ) — (42 ) Total other income (expense), net 40 6 (37 ) 56 (105 ) (40 ) Net Income 40 7 54 51 (105 ) 47 Less: Net (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Net Income Attributable to $ 40 $ 7 $ 58 $ 40 $ (105 ) $ 40 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Six Months Ended June 30, 2015 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 10 $ 379 $ 8 $ — $ 397 Operating Costs and Expenses Cost of operations — 7 135 — — 142 Depreciation and amortization — 2 111 — — 113 General and administrative — affiliate — — — 6 — 6 Acquisition-related transaction and integration costs — — — 1 — 1 Total operating costs and expenses — 9 246 7 — 262 Operating Income — 1 133 1 — 135 Other Income (Expense) Equity in earnings (losses) of consolidated affiliates 21 (19 ) — 45 (47 ) — Equity in earnings of unconsolidated affiliates — — — 10 — 10 Other income, net — — 1 — — 1 Loss on debt extinguishment — — (7 ) — — (7 ) Interest expense — — (87 ) (24 ) — (111 ) Total other income (expense), net 21 (19 ) (93 ) 31 (47 ) (107 ) Net Income (Loss) 21 (18 ) 40 32 (47 ) 28 Less: Net (loss) income attributable to noncontrolling interests — — (4 ) 11 — 7 Net Income (Loss) Attributable to $ 21 $ (18 ) $ 44 $ 21 $ (47 ) $ 21 (a) All significant intercompany transactions have been eliminated in consolidation. For the Three Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 5 $ 168 $ — $ — $ 173 Operating Costs and Expenses Cost of operations — 3 50 — — 53 Depreciation and amortization — 1 53 — — 54 General and administrative — affiliate — — — 2 — 2 Total operating costs and expenses — 4 103 2 — 109 Operating Income (Loss) — 1 65 (2 ) — 64 Other Income (Expense) Equity in earnings of consolidated affiliates 45 2 — 38 (85 ) — Equity in earnings of unconsolidated affiliates — — — 14 — 14 Interest expense — — (28 ) (5 ) — (33 ) Total other income (expense), net 45 2 (28 ) 47 (85 ) (19 ) Net Income $ 45 $ 3 $ 37 $ 45 $ (85 ) $ 45 (a) All significant intercompany transactions have been eliminated in consolidation. NRG YIELD LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Six Months Ended June 30, 2014 NRG Yield LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries NRG Yield Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 12 $ 301 $ — $ — $ 313 Operating Costs and Expenses Cost of operations 8 105 — — 113 Depreciation and amortization 2 76 — — 78 General and administrative — affiliate — — — 4 — 4 Total operating costs and expenses — 10 181 4 — 195 Operating Income (Loss) — 2 120 (4 ) — 118 Other Income (Expense) Equity in earnings of consolidated affiliates 75 2 — 70 (147 ) — Equity in earnings of unconsolidated affiliates — — — 15 — 15 Other income, net — — 1 — — 1 Interest expense — — (53 ) (6 ) — (59 ) Total other income (expense), net 75 2 (52 ) 79 (147 ) (43 ) Net Income $ 75 $ 4 $ 68 $ 75 $ (147 ) $ 75 (a) All significant intercompany transactions have been eliminated in consolidation.

Nature of Business (Details)

Nature of Business (Details) $ / shares in Units, $ in Millions		Jun. 29, 2015USD ($)$ / sharesshares	Jan. 02, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)MW	Jun. 30, 2014USD ($)		Jun. 30, 2015USD ($)MW	Jun. 30, 2014USD ($)
Nature of Business
Megawatts Thermal Equivalent, Available Under right-to-use Provisions					134			134
Power Generation Capacity (in MWs)	[1]				3,949			3,949
General and administrative — affiliate | $					$ 3	$ 2		$ 6	$ 4
Business Combination, Consideration Transferred | $								37	0
Proceeds from Issuance of Common Stock | $								$ 600	0
Distributed Solar
Nature of Business
Power Generation Capacity (in MWs)	[1]				10			10
Wind Farms [Member]
Nature of Business
Power Generation Capacity (in MWs)	[1]				1,389			1,389
Thermal [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Steam and Chilled Water Capacity, Megawatts Thermal Equivalent	[1],[2]				1,310			1,310
Power Generation Capacity (in MWs)	[1]				124			124
Conventional
Nature of Business
Power Generation Capacity (in MWs)	[1]				1,945			1,945
Utility-Scale Solar
Nature of Business
Power Generation Capacity (in MWs)	[1]				481			481
NRG Yield LLC
Nature of Business
General and administrative — affiliate | $					$ 0	0		$ 0	0
Business Combination, Consideration Transferred | $								0	0
Proceeds from Issuance of Common Stock | $								$ 600
NRG Yield LLC | NRG Yield, Inc. [Member]
Nature of Business
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Voting Interest		44.90%
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest		53.30%
GenConn Middletown | Conventional
Nature of Business
Equity Method Investment, Ownership Percentage					49.95%			49.95%
Power Generation Capacity (in MWs)	[1]				95			95
GenConn Devon [Member] | Conventional
Nature of Business
Equity Method Investment, Ownership Percentage					49.95%			49.95%
Power Generation Capacity (in MWs)	[1]				95			95
Marsh Landing | Conventional
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				720			720
El Segundo [Member] | Conventional
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				550			550
Walnut Creek [Member] | Conventional
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				485			485
Alpine | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				66			66
Avenal | Utility-Scale Solar
Nature of Business
Equity Method Investment, Ownership Percentage					49.95%			49.95%
Power Generation Capacity (in MWs)	[1]				23			23
Avra Valley | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				25			25
NRG Solar Blythe LLC [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				21			21
Borrego | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				26			26
Roadrunner | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				20			20
CVSR | Utility-Scale Solar
Nature of Business
Equity Method Investment, Ownership Percentage					48.95%			48.95%
Power Generation Capacity (in MWs)	[1]				122			122
RE Kansas South [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				20			20
TA - High Desert LLC [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				20			20
Desert Sunlight [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership					25.00%			25.00%
AZ DG Solar Projects | Distributed Solar
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				5			5
PFMG DG Solar Projects | Distributed Solar
Nature of Business
Percentage of Ownership					51.00%			51.00%
Power Generation Capacity (in MWs)	[1]				5			5
Alta I [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				150			150
Alta II [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				150			150
Alta III [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				150			150
Alta IV [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				102			102
Alta V [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				168			168
Alta X [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1],[3]				137			137
Alta XI [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1],[3]				90			90
South Trent | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				101			101
Laredo Ridge [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				80			80
Taloga [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				130			130
Pinnacle [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				55			55
Buffalo Bear [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					100.00%			100.00%
Power Generation Capacity (in MWs)	[1]				19			19
Spring Canyon II [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					90.10%			90.10%
Power Generation Capacity (in MWs)	[1]				31			31
Spring Canyon III [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership					90.10%			90.10%
Power Generation Capacity (in MWs)	[1]				26			26
Drop-down Acquisition [Member]
Nature of Business
Business Combination, Consideration Transferred | $				$ 357				$ 489	336
Drop-down Acquisition [Member] | NRG Yield LLC
Nature of Business
Business Combination, Consideration Transferred | $								0
EME-NYLD Assets [Member]
Nature of Business
Business Combination, Consideration Transferred | $			$ 489
Business Combination, Consideration Transferred, Liabilities Incurred | $			737
Business Acquisition, Consideration Transferred, Working Capital | $			$ 9
Affiliated Entity [Member]
Nature of Business
General and administrative — affiliate | $					$ 3	$ 2	[4]	$ 6	$ 4	[4]
Southern California Edison [Member] | Desert Sunlight [Member] | Utility-Scale Solar
Nature of Business
Power Generation Capacity (in MWs)	[1]				63			63
Pacific Gas and Electric [Member] | Desert Sunlight [Member] | Utility-Scale Solar
Nature of Business
Power Generation Capacity (in MWs)	[1]				75			75
Common Class B [Member] | NRG Yield LLC
Nature of Business
Sale of Stock, Percentage of Ownership after Transaction								100.00%
Common Class C [Member]
Nature of Business
Sale of Stock, Price Per Share | $ / shares		$ 22
Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions | $		$ 20
Common Class C [Member] | NRG Yield, Inc. [Member] | Public Shareholders [Member]
Nature of Business
Sale of Stock, Number of Shares Issued in Transaction | shares		28,198,000
Proceeds from Issuance of Common Stock | $		$ 600
[1]	Net capacity represents the maximum, or rated, generating capacity of the facility multiplied by the Company's percentage ownership in the facility as of June 30, 2015.
[2]	For thermal energy, net capacity represents MWt for steam or chilled water and excludes 134 MWt available under the right-to-use provisions contained in agreements between two of the Company's thermal facilities and certain of its customers.
[3]	{F|ahBzfndlYmZpbGluZ3MtaHJkcmoLEgZYTUxEb2MiXlhCUkxEb2NHZW5JbmZvOjc4YjMzOWYxMDI5ZDQ4MmJhMDhmYjE2ZDk1ZTEyNjBjfFRleHRTZWxlY3Rpb246RTc4MEUxMUUwNEM5QzFCRjA4QzFENEU4RTQxODJEQUQM}
[4]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Summary of Significant Accoun30

Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions	Jun. 30, 2015	May. 07, 2015	Jan. 02, 2015	Jun. 30, 2015	Mar. 31, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014		Dec. 31, 2014
Summary of Significant Accounting Policies [Line Items]
Dividends Payable, Date of Record							Sep. 1, 2015
Dividends Per Class A Common Share					$ 0.39
Dividends Payable, Date to be Paid							Sep. 15, 2015
Dividends Payable, Date Declared							Aug. 4, 2015
Common Stock, Dividends, Per Share, Declared							$ 0.21
New Accounting Pronouncement, Effect on Total Assets and Total Liabilities	$ 55			$ 55			$ 55			$ 61
Proceeds from Noncontrolling Interests							(119)	$ 0
Stockholders' Equity Attributable to Noncontrolling Interest	$ 200			200			200			$ 0	[1]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest				$ 7		$ 0	7	0
Payments of Dividends							61	$ 44	[2]
EME-NYLD Assets [Member]
Summary of Significant Accounting Policies [Line Items]
Business Combination, Separately Recognized Transactions, Net Gains and Losses			$ 61
Accumulated Other Comprehensive Income (Loss), before Tax			$ 23
Noncontrolling Interest [Member]
Summary of Significant Accounting Policies [Line Items]
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest							$ 7
Wind Farms [Member] | Spring Canyon [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners	9.90%			9.90%			9.90%
Percentage of Ownership	90.10%			90.10%			90.10%
Alta X and XI TE Holdco [Member] | Financial Institutions [Member]
Summary of Significant Accounting Policies [Line Items]
Proceeds from Noncontrolling Interests	$ (119)
Spring Canyon [Member] | Financial Institutions [Member]
Summary of Significant Accounting Policies [Line Items]
Noncontrolling Interest, Increase from Business Combination		$ 74
Common Class C [Member]
Summary of Significant Accounting Policies [Line Items]
Dividends Per Class A Common Share				$ 0.20
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Business Acquisitions (Details)

Business Acquisitions (Details) - Long-term Contract for Purchase of Electric Power [Domain]		Jun. 29, 2015USD ($)	Jan. 02, 2015USD ($)	Aug. 12, 2014USD ($)MW	Aug. 05, 2014USD ($)	Jul. 29, 2014USD ($)$ / sharesshares	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)MW	Jun. 30, 2014USD ($)		Dec. 31, 2014USD ($)		Jun. 30, 2015USD ($)MW	Jun. 30, 2014USD ($)
Business Acquisition
Assets, Current								$ 478,000,000			$ 590,000,000	[1]	$ 478,000,000
Total operating revenues								217,000,000	$ 173,000,000	[2]			397,000,000	$ 313,000,000	[2]
Property, Plant and Equipment, Net								$ 4,478,000,000			4,466,000,000	[1]	4,478,000,000
Business Combination, Consideration Transferred													$ 37,000,000	0
Non-current assets											1,770,000,000
Power Generation Capacity (in MWs) | MW	[3]							3,949					3,949
Proceeds from Issuance of Common Stock													$ 600,000,000	0
Long-term Debt								$ 4,769,000,000			4,798,000,000		4,769,000,000
Total Assets								7,044,000,000			6,826,000,000	[1]	7,044,000,000
Other Liabilities											292,000,000
Liabilities								5,028,000,000			5,090,000,000	[1]	5,028,000,000
Net Assets											1,736,000,000
Operating Income (Loss)								87,000,000	64,000,000	[2]			135,000,000	118,000,000	[2]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest								47,000,000	45,000,000	[2],[4]			28,000,000	75,000,000	[2],[4],[5]
Other Assets								2,088,000,000			1,770,000,000	[1]	2,088,000,000
NRG Yield Operating LLC [Member]
Business Acquisition
Assets, Current								162,000,000			268,000,000		162,000,000
Total operating revenues								(1,000,000)	0				8,000,000	0
Property, Plant and Equipment, Net								0			0		0
Business Combination, Consideration Transferred													37,000,000	357,000,000
Proceeds from Issuance of Common Stock													0
Total Assets								3,394,000,000			2,550,000,000		3,394,000,000
Liabilities								1,448,000,000			886,000,000		1,448,000,000
Operating Income (Loss)								(5,000,000)	(2,000,000)				1,000,000	(4,000,000)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest								51,000,000	45,000,000				32,000,000	75,000,000
Other Assets								$ 3,232,000,000			2,282,000,000		$ 3,232,000,000
5.375% Senior Notes due in 2024 [Member]
Business Acquisition
Debt Instrument, Interest Rate, Stated Percentage								5.375%					5.375%
5.375% Senior Notes due in 2024 [Member] | NRG Yield Operating LLC [Member]
Business Acquisition
Proceeds from Issuance of Senior Long-term Debt					$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage					5.375%
Alta Wind Portfolio [Member]
Business Acquisition
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents				$ 22,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Cash											0
Number of Facilities				7
Payments to Acquire Businesses, Gross				$ 923,000,000
Business Combination, Consideration Transferred				870,000,000
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment				1,304,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles				1,177,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles											(6,000,000)
Business Acquisition, Purchase Price Allocation, Intangible Assets, Other than Goodwill, Adjusted				1,171,000,000
Business Acquisition, Consideration Transferred, Working Capital				$ 53,000,000
Power Generation Capacity (in MWs) | MW				947
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted				$ 923,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment											6,000,000
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment, Adjusted				1,310,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt				1,591,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Noncurrent Liabilities Longterm Debt											0
Business Acquisition, Purchase Price Allocation, Noncurrent Liabilities, Long-term Debt, Adjusted				1,591,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current and Non-Current Assets				49,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Assets											(2,000,000)
Business Acquisition, Purchase Price Allocation, Other Assets, Adjusted				47,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets				2,552,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Assets											(2,000,000)
Business Acquisition, Purchase Price Allocation, Assets Acquired, Adjusted				2,550,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current and Non-Current Liabilities				38,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current and Noncurrent Liabilities											(2,000,000)
Business Acquisition, Purchase Price Allocation, Current and Non-current Liabilities, Adjusted				36,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities				1,629,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities											(2,000,000)
Business Acquisition, Purchase Price Allocation, Liabilities Assumed, Adjusted				1,627,000,000
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Net Assets Acquired											0
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted				$ 923,000,000
Alta Wind Portfolio [Member] | Leasehold Rights [Member]
Business Acquisition
Weighted average remaining amortization period (in years)													21 years
Alta Wind Portfolio [Member] | Supply Commitment Arrangement [Domain]
Business Acquisition
Weighted average remaining amortization period (in years)													22 years
Tapestry Wind [Member]
Business Acquisition
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets											14,000,000
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment											286,000,000
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted											164,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets											361,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities											197,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets											61,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt											192,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Current and Non-Current Liabilities											5,000,000
Laredo Ridge [Member]
Business Acquisition
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets											7,000,000
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment											118,000,000
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted											62,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets											174,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities											112,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets											49,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt											108,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Current and Non-Current Liabilities											4,000,000
Walnut Creek [Member]
Business Acquisition
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets											46,000,000
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment											575,000,000
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted											179,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets											678,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities											499,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets											57,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Long-term Debt											437,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Current and Non-Current Liabilities											62,000,000
EME-NYLD Assets [Member]
Business Acquisition
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual													$ 73,000,000
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual													$ 23,000,000
Business Acquisition, Pro Forma Revenue														339,000,000
Business Combination, Consideration Transferred			$ 489,000,000
Business Acquisition, Consideration Transferred, Working Capital			9,000,000
Business Combination, Consideration Transferred, Liabilities Incurred			737,000,000
Business Acquisition, Pro Forma Net Income(Loss), Including Portion Attributable to Noncontrolling Interest														71,000,000
Business Combination, Separately Recognized Transactions, Net Gains and Losses			61,000,000
Accumulated Other Comprehensive Income (Loss), before Tax			$ 23,000,000
Acquired ROFO Assets [Domain]
Business Acquisition
Business Combination, Consideration Transferred							$ 357,000,000
Business Acquisition, Consideration Transferred, Working Capital							8,000,000		8,000,000					8,000,000
Business Combination, Consideration Transferred, Liabilities Incurred							612,000,000
Business Acquisitions, Consideration Transferred, Purchase Price							$ 349,000,000		$ 349,000,000					$ 349,000,000
Utility-Scale Solar [Member]
Business Acquisition
Power Generation Capacity (in MWs) | MW	[3]							481					481
Thermal [Member]
Business Acquisition
Percentage of Ownership								100.00%					100.00%
Power Generation Capacity (in MWs) | MW	[3]							124					124
Thermal [Member] | UB Fuel Cell [Member]
Business Acquisition
Power Generation Capacity (in MWs) | MW								1.4					1.4
Wind Farms [Member]
Business Acquisition
Power Generation Capacity (in MWs) | MW	[3]							1,389					1,389
Wind Farms [Member] | Spring Canyon II [Member]
Business Acquisition
Percentage of Ownership								90.10%					90.10%
Power Generation Capacity (in MWs) | MW	[3]							31					31
Wind Farms [Member] | Laredo Ridge [Member]
Business Acquisition
Percentage of Ownership								100.00%					100.00%
Power Generation Capacity (in MWs) | MW	[3]							80					80
Wind Farms [Member] | Spring Canyon III [Member]
Business Acquisition
Percentage of Ownership								90.10%					90.10%
Power Generation Capacity (in MWs) | MW	[3]							26					26
Wind Farms [Member] | Spring Canyon [Member]
Business Acquisition
Percentage of Ownership								90.10%					90.10%
Wind Farms [Member] | Spring Canyon III [Member]
Business Acquisition
Power Generation Capacity (in MWs) | MW								29					29
Wind Farms [Member] | Spring Canyon II [Member]
Business Acquisition
Power Generation Capacity (in MWs) | MW								34					34
Scenario, Previously Reported [Member]
Business Acquisition
Assets, Current											523,000,000
Property, Plant and Equipment, Net											3,487,000,000
Non-current assets											1,603,000,000
Long-term Debt											4,061,000,000
Total Assets											5,613,000,000
Other Liabilities											221,000,000
Liabilities											4,282,000,000
Net Assets											$ 1,331,000,000
Common Class A [Member] | Public Shareholders [Member]
Business Acquisition
Sale of Stock, Number of Shares Issued in Transaction | shares						12,075,000
Share Price | $ / shares						$ 54
Proceeds from Issuance of Common Stock						$ 630,000,000
Desert Sunlight [Member]
Business Acquisition
Payments to Acquire Businesses, Gross		$ 285,000,000
Power Generation Capacity (in MWs) | MW								550					550
Desert Sunlight [Member] | Utility-Scale Solar [Member]
Business Acquisition
Percentage of Ownership								25.00%					25.00%
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	Net capacity represents the maximum, or rated, generating capacity of the facility multiplied by the Company's percentage ownership in the facility as of June 30, 2015.
[4]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[5]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Property, Plant and Equipment32

Property, Plant and Equipment (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment
Property, plant and equipment, gross	$ 4,927	$ 4,804	[1]
Under construction	8	8	[1]
Less accumulated depreciation	(449)	(338)	[1]
Property, Plant and Equipment, Net	4,478	4,466	[1]
Support Equipment and Facilities [Member]
Property, Plant and Equipment
Property, plant and equipment, gross	4,832	4,709
Land and improvements
Property, Plant and Equipment
Property, plant and equipment, gross	$ 87	$ 87
Minimum [Member] | Support Equipment and Facilities [Member]
Property, Plant and Equipment
Property, plant and equipment, useful life	2 years
Maximum [Member] | Support Equipment and Facilities [Member]
Property, Plant and Equipment
Property, plant and equipment, useful life	40 years
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Investments Accounted for by 33

Investments Accounted for by the Equity Method and Variable Interest Entities (Details) - Scenario, Unspecified [Domain]		Jun. 30, 2015USD ($)facilityMW	Jun. 12, 2015USD ($)	Apr. 09, 2015USD ($)generatingunitMW	Jun. 30, 2015USD ($)facilityMW	Jun. 30, 2014USD ($)		Jun. 30, 2015USD ($)facilityMW	Jun. 30, 2014USD ($)		Dec. 31, 2014USD ($)
Variable Interest Entity
Other Assets		$ 2,088,000,000			$ 2,088,000,000			$ 2,088,000,000			$ 1,770,000,000	[1]
Property, Plant and Equipment, Net		4,478,000,000			4,478,000,000			4,478,000,000			4,466,000,000	[1]
Assets		7,044,000,000			7,044,000,000			7,044,000,000			6,826,000,000	[1]
Liabilities		$ 5,028,000,000			$ 5,028,000,000			5,028,000,000			5,090,000,000	[1]
Proceeds from Noncontrolling Interests								$ 119,000,000	$ 0
Power Generation Capacity (in MWs) | MW	[2]	3,949			3,949			3,949
Long-term Debt		$ 4,769,000,000			$ 4,769,000,000			$ 4,769,000,000			4,798,000,000
Total operating revenues					217,000,000	$ 173,000,000	[3]	397,000,000	313,000,000	[3]
Operating income					(87,000,000)	(64,000,000)	[3]	(135,000,000)	(118,000,000)	[3]
Net Income					47,000,000	45,000,000	[3],[4]	28,000,000	75,000,000	[3],[4],[5]
Assets, Current		478,000,000			478,000,000			478,000,000			590,000,000	[1]
Non-current assets											1,770,000,000
Liabilities, Current		570,000,000			570,000,000			570,000,000			388,000,000	[1]
Liabilities, Noncurrent		4,458,000,000			4,458,000,000			4,458,000,000			4,702,000,000	[1]
Equity Method Investments		549,000,000			549,000,000			549,000,000			227,000,000	[1]
(Investments in) Proceeds From Sales of Unconsolidated Affiliates								(313,000,000)	(15,000,000)	[5]
Net Assets											1,736,000,000
Business Combination, Consideration Transferred								37,000,000	0
Alta X and XI TE Holdco [Member]
Variable Interest Entity
Other Assets		11,000,000			11,000,000			11,000,000
Property, Plant and Equipment, Net		493,000,000			493,000,000			493,000,000
Intangible Assets, Net (Excluding Goodwill)		287,000,000			287,000,000			287,000,000
Assets		791,000,000			791,000,000			791,000,000
Liabilities		8,000,000			8,000,000			8,000,000
Noncontrolling Interest in Variable Interest Entity		130,000,000			130,000,000			130,000,000
Net Assets		$ 653,000,000			$ 653,000,000			$ 653,000,000
Gen Conn Energy LLC [Member]
Variable Interest Entity
Power Generation Capacity (in MWs) | MW		190			190			190
Power Generation Units, Number | facility		2			2			2
NRG RPV Holdco [Member]
Variable Interest Entity
Equity Method Investments		$ 40,000,000			$ 40,000,000			$ 40,000,000
GCE Holdings LLC
Variable Interest Entity
Economic interest in equity method investments (as a percent)		49.95%			49.95%			49.95%
Total operating revenues					$ 18,000,000	18,000,000		$ 40,000,000	44,000,000
Operating income					11,000,000	10,000,000		20,000,000	20,000,000
Net Income					8,000,000	$ 7,000,000		14,000,000	$ 14,000,000
Assets, Current		$ 37,000,000			37,000,000			37,000,000			33,000,000
Non-current assets		424,000,000			424,000,000			424,000,000			438,000,000
Liabilities, Current		16,000,000			16,000,000			16,000,000			20,000,000
Liabilities, Noncurrent		219,000,000			219,000,000			219,000,000			$ 223,000,000
Gen Conn Energy LLC [Member]
Variable Interest Entity
Equity Method Investments		113,000,000			113,000,000			113,000,000
Gen Conn Energy LLC [Member] | Fixed Rate Notes
Variable Interest Entity
Long-term Debt		$ 224,000,000			$ 224,000,000			$ 224,000,000
Interest rate		4.73%			4.73%			4.73%
Line of Credit Facility, Maximum Borrowing Capacity		$ 237,000,000			$ 237,000,000			$ 237,000,000
Gen Conn Energy LLC [Member] | Working Capital Facility [Member]
Variable Interest Entity
Interest rate		1.875%			1.875%			1.875%
Line of Credit Facility, Maximum Borrowing Capacity		$ 35,000,000			$ 35,000,000			$ 35,000,000
Line of Credit Facility, Fair Value of Amount Outstanding		0			0			0
Existing Portfolio of Leases [Member] | NRG RPV Holdco [Member]
Variable Interest Entity
Number of Solar Leases in Portfolio | generatingunit				2,200
Power Generation Capacity (in MWs) | MW				17
Remaining Lease Term				17 years
Equity Method Investments				$ 26,000,000
Tax Equity Financed Portfolio of Leases [Member] | NRG DGPV Holdco [Member]
Variable Interest Entity
Equity Method Investments				$ 19,000,000
(Investments in) Proceeds From Sales of Unconsolidated Affiliates								4,000,000
Due to Related Parties		$ 15,000,000			$ 15,000,000			$ 15,000,000
Tax Equity Financed Portfolio of Leases [Member] | NRG RPV Holdco [Member]
Variable Interest Entity
Number of Solar Leases in Portfolio | generatingunit				13,000
Power Generation Capacity (in MWs) | MW				90
Equity Method Investments				$ 14,000,000
Tax Equity Financed Portfolio of Leases [Member] | Minimum [Member] | NRG RPV Holdco [Member]
Variable Interest Entity
Remaining Lease Term				17 years
Tax Equity Financed Portfolio of Leases [Member] | Maximum [Member] | NRG RPV Holdco [Member]
Variable Interest Entity
Remaining Lease Term				20 years
Equity Method Investments				$ 150,000,000
Financial Institutions [Member] | Alta X and XI TE Holdco [Member]
Variable Interest Entity
Taxable Income Allocation, Pre-Flip		99.00%			99.00%			99.00%
Proceeds from Noncontrolling Interests		$ 119,000,000
Taxable Income Allocation, Post-Flip		5.00%			5.00%			5.00%
NRG Renew [Member] | NRG DGPV Holdco [Member]
Variable Interest Entity
Business Acquisitions, Consideration Transferred, Purchase Price			$ 32,000,000
Business Combination, Consideration Transferred			$ 7,000,000
Post-Flip Point [Member] | Alta X and XI TE Holdco [Member]
Variable Interest Entity
Percentage of Cash Available for Distributions		97.12%			97.12%			97.12%
Pre-determined Date Through Flip Point If Flip Has Not Occured [Member] | Alta X and XI TE Holdco [Member]
Variable Interest Entity
Percentage of Cash Available for Distributions		100.00%			100.00%			100.00%
Second Year through Flip Point [Member] | Alta X and XI TE Holdco [Member]
Variable Interest Entity
Percentage of Cash Available for Distributions		94.34%			94.34%			94.34%
First Year [Member] | Alta X and XI TE Holdco [Member]
Variable Interest Entity
Percentage of Cash Available for Distributions		100.00%			100.00%			100.00%
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	Net capacity represents the maximum, or rated, generating capacity of the facility multiplied by the Company's percentage ownership in the facility as of June 30, 2015.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[4]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[5]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Fair Value of Financial Instr34

Fair Value of Financial Instruments (Details) - Entity [Domain] - USD ($)		6 Months Ended
		Jun. 30, 2015	Dec. 31, 2014
Fair Value of Financial Instruments
Derivative Liability, Fair Value Determined Using Valuation Techniques, Percentage		0.00%
Fair Value Assets, Measured on Recurring Basis, Valuation Techniques, Impact of Credit Reserve to Fair Value		$ 1,000,000
Derivative Assets		8,000,000	$ 2,000,000
Long-term debt, including current portion		$ 4,769,000,000	4,798,000,000
Derivative Asset, Fair Value Determined Using Valuation Techniques, Percentage		0.00%
Derivative Liabilities		$ 87,000,000	117,000,000
Concentration of Credit Risk
Credit risk exposure under certain long-term agreements for the next five years		$ 2,400,000,000
Period of credit risk exposure under certain long-term agreements (in years)		5 years
Due to Affiliate, Noncurrent		$ 618,000,000	337,000,000	[1]
Interest rate contracts
Fair Value of Financial Instruments
Derivative Assets		4,000,000	2,000,000
Derivative Liabilities		84,000,000	114,000,000
Commodity contracts
Fair Value of Financial Instruments
Derivative Assets		4,000,000	0
Derivative Liabilities		3,000,000	3,000,000
Fair Value, Inputs, Level 2 [Member]
Fair Value of Financial Instruments
Derivative Assets	[2]	8,000,000	2,000,000
Reported Value Measurement [Member]
Fair Value of Financial Instruments
Financing Receivable, Net		20,000,000	21,000,000
Concentration of Credit Risk
Long-term Debt and Capital Lease Obligations, Including Current Maturities		4,151,000,000	4,461,000,000
Estimate of Fair Value Measurement [Member]
Fair Value of Financial Instruments
Financing Receivable, Net		20,000,000	21,000,000
Concentration of Credit Risk
Due to Affiliate, Noncurrent		643,000,000	386,000,000
Long-term Debt and Capital Lease Obligations, Including Current Maturities		4,155,000,000	4,478,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value of Financial Instruments
Derivative Assets (Liabilities), at Fair Value, Net		0	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value of Financial Instruments
Derivative Liabilities	[2]	87,000,000	117,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Interest rate contracts
Fair Value of Financial Instruments
Derivative Assets	[2]	4,000,000	2,000,000
Derivative Liabilities	[2]	84,000,000	114,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member] | Commodity contracts
Fair Value of Financial Instruments
Derivative Assets	[2]	4,000,000	0
Derivative Liabilities	[2]	3,000,000	3,000,000
Fair Value, Measurements, Recurring [Member] | Level 1
Fair Value of Financial Instruments
Derivative Assets (Liabilities), at Fair Value, Net			$ 0
Gain (Loss) on Derivative Instruments [Member]
Fair Value of Financial Instruments
Fair Value Assets, Measured on Recurring Basis, Valuation Techniques, Impact of Credit Reserve to Fair Value		$ 1,000,000
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) There were no assets or liabilities classified as Level 1 or Level 3 as of June 30, 2015, or December 31, 2014.

Accounting for Derivative Ins35

Accounting for Derivative Instruments and Hedging Activities (Details) - USD ($) pure in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Derivative
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net			$ 0	$ 0
Fair Value of Derivative Instruments
Derivative Liabilities	$ (87)		(87)		$ (117)
Derivative Assets	8		8		2
Derivative Asset	4		4		0	[1]
Fair Value of Gross Derivative Assets/(Liabilities), Net	(79)		(79)		(115)
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset	0		0		0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral	(79)		(79)		(115)
Accumulated Other Comprehensive Income (Loss), Net of Tax
Accumulated OCL beginning balance	(83)	$ (13)	(58)	(1)
Mark-to-market of cash flow hedge accounting contracts	21	(26)	(7)	(41)
Accumulated OCL ending balance, net of income tax benefit of $14 and $1, respectively	(58)	(35)	(58)	(35)
Loss expected to be realized from OCI during the next 12 months, net of tax			(17)
Summary of Derivative Instruments Impact on Results of Operations
Derivative, Collateral, Right to Reclaim Cash	0		0		0
Derivative, Collateral, Obligation to Return Cash	$ 0		$ 0		0
Derivative Asset, Fair Value Determined Using Valuation Techniques, Percentage	0.00%		0.00%
Reclassification out of Accumulated Other Comprehensive Income
Accumulated Other Comprehensive Income (Loss), Net of Tax
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	$ 4	4	$ 7	7
Derivatives Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(79)		(79)		(89)
Derivative Assets	4		4		2
Derivatives Not Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(8)		(8)		(28)
Derivative Assets	4		4		0
Interest rate contracts current | Derivatives Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(37)		(37)		(40)
Derivative Assets	0		0		0
Interest rate contracts current | Derivatives Not Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(3)		(3)		(5)
Derivative Assets	0		0		0
Interest rate contracts long-term | Derivatives Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(42)		(42)		(49)
Derivative Assets	4		4		2
Interest rate contracts long-term | Derivatives Not Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(2)		(2)		(20)
Derivative Assets	0		0		0
Commodity contracts current | Derivatives Not Designated as Cash Flow Hedges
Fair Value of Derivative Instruments
Derivative Liabilities	(3)		(3)		(3)
Derivative Assets	4		4		0
Commodity contracts
Derivative
Derivative Liability	(2)		(2)		(3)
Fair Value of Derivative Instruments
Derivative Liabilities	(3)		(3)		(3)
Derivative Assets	4		4		0
Derivative Asset	3		3		0
Fair Value of Gross Derivative Assets/(Liabilities), Net	1		1		(3)
Derivative Liability, Fair Value, Gross Asset	1		1		0
Derivative Asset, Fair Value, Gross Liability	(1)		(1)		0
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset	0		0		0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral	1		1		(3)
Interest rate contracts
Derivative
Derivative Liability	(81)		(81)		(112)
Fair Value of Derivative Instruments
Derivative Liabilities	(84)		(84)		(114)
Derivative Assets	4		4		2
Derivative Asset	1		1		0
Fair Value of Gross Derivative Assets/(Liabilities), Net	(80)		(80)		(112)
Derivative Liability, Fair Value, Gross Asset	3		3		2
Derivative Asset, Fair Value, Gross Liability	(3)		(3)		(2)
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset	0		0		0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral	(80)		(80)		(112)
Interest Expense [Member] | Interest rate contracts
Summary of Derivative Instruments Impact on Results of Operations
Unrealized gain/(loss) on derivatives	31	(3)	19	(6)
Operating Revenues [Member] | Commodity contracts
Summary of Derivative Instruments Impact on Results of Operations
Unrealized gain/(loss) on derivatives	(4)	$ 0	3	$ 0
Natural Gas [Member] | MMbtu
Derivative
Derivative, Notional Amount	3		3		2
Interest | Dollars
Derivative
Derivative, Notional Amount	$ 1,841		$ 1,841		$ 2,817
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Long-term Debt (Details)

Long-term Debt (Details)	Jun. 30, 2015USD ($)	Jun. 29, 2015USD ($)$ / shares	May. 29, 2015USD ($)	Mar. 18, 2015USD ($)	Dec. 17, 2014USD ($)	Nov. 12, 2014	Oct. 21, 2014USD ($)	Aug. 05, 2014USD ($)	Dec. 21, 2011USD ($)	Jul. 27, 2011USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Jun. 30, 2015USD ($)	Jun. 30, 2014USD ($)	Dec. 31, 2014USD ($)		Jul. 27, 2010USD ($)
Long-term Debt Disclosure
Due to Affiliate, Noncurrent	$ 618,000,000											$ 618,000,000		$ 618,000,000		$ 337,000,000	[1]
Long-term Debt	4,769,000,000											4,769,000,000		4,769,000,000		4,798,000,000
Long-term debt, excluding current maturities	4,362,000,000											4,362,000,000		4,362,000,000		4,584,000,000
Proceeds from Noncontrolling Interests														119,000,000	$ 0
Gains (Losses) on Extinguishment of Debt												(7,000,000)	$ 0	(7,000,000)	$ 0
NRG Yield Operating LLC [Member]
Long-term Debt Disclosure
Due to Affiliate, Noncurrent	618,000,000											618,000,000		618,000,000		337,000,000
Proceeds from Noncontrolling Interests														119,000,000
Gains (Losses) on Extinguishment of Debt												0		0
NRG Yield LLC [Member]
Long-term Debt Disclosure
Distribution Made to Limited Liability Company (LLC) Member, Cash Distributions Paid					$ 33,000,000
WCEP Holdings LLC [Member]
Long-term Debt Disclosure
Distribution Made to Limited Liability Company (LLC) Member, Cash Distributions Paid							$ 6,000,000
3.25% Convertible Notes due 2020 [Member]
Long-term Debt Disclosure
Convertible Debt		$ 287,500,000
Due to Affiliate, Noncurrent	$ 281,000,000											$ 281,000,000		$ 281,000,000		0
Interest rate	3.325%											3.325%		3.325%
Debt Instrument, Convertible, Conversion Price | $ / shares		$ 27.50
Debt Instrument, Convertible, Conversion Ratio		36.3636
3.5% Convertible Notes due 2019 [Member]
Long-term Debt Disclosure
Due to Affiliate, Noncurrent	$ 337,000,000											$ 337,000,000		$ 337,000,000		337,000,000
Interest rate	3.58%											3.58%		3.58%
Alta Wind I, lease financing arrangement, due 2034 [Member] | Non-affiliate
Long-term Debt Disclosure
Interest rate	7.015%											7.015%		7.015%
Alta Realty Investments, due 2031 [Member] | Non-affiliate
Long-term Debt Disclosure
Interest rate	7.00%											7.00%		7.00%
NRG Marsh Landing LLC, due 2017 and 2023 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 454,000,000											$ 454,000,000		$ 454,000,000		464,000,000
NRG Marsh Landing LLC, due 2023
Long-term Debt Disclosure
Variable rate basis														1 month LIBOR
Basis spread on variable rate														1.875%
Walnut Creek Energy, LLC, due in 2023 [Member]
Long-term Debt Disclosure
Variable rate basis														1 month LIBOR
Basis spread on variable rate														1.625%
Walnut Creek Energy, LLC, due in 2023 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Percentage of Debt Hedged by Interest Rate Derivatives										90.00%
Derivative, Fixed Interest Rate							4.0025%			3.54%
Walnut Creek Energy, LLC, due in 2023 [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	381,000,000											381,000,000		$ 381,000,000		391,000,000
Walnut Creek Energy, LLC, due in 2023 [Member] | Term Loan Facility
Long-term Debt Disclosure
Debt Issuance Cost							$ 4,000,000
Long-term Debt										$ 442,000,000
Proceeds from Issuance of Debt							$ 10,000,000
Walnut Creek Energy, LLC, due in 2023 [Member] | Working Capital Facility [Member]
Long-term Debt Disclosure
Line of Credit Facility, Commitment Fee Percentage							0.50%			0.625%
Line of Credit Facility, Maximum Borrowing Capacity										$ 5,000,000
Line of Credit Facility, Fair Value of Amount Outstanding	0											0		0
Walnut Creek Energy, LLC, due in 2023 [Member] | Letter of Credit [Member]
Long-term Debt Disclosure
Letters of Credit Outstanding, Amount	61,000,000											61,000,000		$ 61,000,000
Line of Credit Facility, Maximum Borrowing Capacity										$ 117,000,000
Marsh Landing Tranche A due December 2017 [Member]
Long-term Debt Disclosure
Variable rate basis														1 month LIBOR
Basis spread on variable rate														1.75%
NRG Solar Alpine, due 2022
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Tapestry Wind LLC due in 2021 [Member]
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														1.625%
Tapestry Wind LLC due in 2021 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Percentage of Debt Hedged by Interest Rate Derivatives									90.00%
Derivative, Fixed Interest Rate									2.21%
Derivative, Forward Interest Rate									3.57%
Tapestry Wind LLC due in 2021 [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	185,000,000											185,000,000		$ 185,000,000		192,000,000
Tapestry Wind LLC due in 2021 [Member] | Term Loan Facility
Long-term Debt Disclosure
Long-term Debt									$ 214,000,000
Tapestry Wind LLC due in 2021 [Member] | Working Capital Facility [Member]
Long-term Debt Disclosure
Line of Credit Facility, Commitment Fee Percentage									0.75%
Line of Credit Facility, Maximum Borrowing Capacity									$ 8,000,000
Line of Credit Facility, Fair Value of Amount Outstanding	0											0		0
Tapestry Wind LLC due in 2021 [Member] | Letter of Credit [Member]
Long-term Debt Disclosure
Letters of Credit Outstanding, Amount	20,000,000											20,000,000		20,000,000
Line of Credit Facility, Maximum Borrowing Capacity									$ 20,000,000
Alpine Financing Agreement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	161,000,000											161,000,000		$ 161,000,000		163,000,000
Laredo Ridge Wind, LLC, due in 2026 [Member]
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														1.875%
Laredo Ridge Wind, LLC, due in 2026 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Percentage of Debt Hedged by Interest Rate Derivatives					75.00%
Laredo Ridge Wind, LLC, due in 2026 [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	106,000,000											106,000,000		$ 106,000,000		108,000,000
Laredo Ridge Wind, LLC, due in 2026 [Member] | Cash Grant Loan
Long-term Debt Disclosure
Long-term Debt																		$ 53,000,000
Laredo Ridge Wind, LLC, due in 2026 [Member] | Term Loan Facility
Long-term Debt Disclosure
Debt Issuance Cost					$ 8,000,000
Long-term Debt																		75,000,000
Proceeds from Issuance of Debt					$ 41,000,000
Laredo Ridge Wind, LLC, due in 2026 [Member] | Working Capital Facility [Member]
Long-term Debt Disclosure
Line of Credit Facility, Commitment Fee Percentage					0.50%
Line of Credit Facility, Maximum Borrowing Capacity																		3,000,000
Credit Facility, Maximum Borrowing Capacity, Amendment					$ 1,000,000
Line of Credit Facility, Fair Value of Amount Outstanding	0											0		0
Laredo Ridge Wind, LLC, due in 2026 [Member] | Letter of Credit [Member]
Long-term Debt Disclosure
Letters of Credit Outstanding, Amount	10,000,000											10,000,000		10,000,000
Line of Credit Facility, Maximum Borrowing Capacity																		$ 9,000,000
Credit Facility, Maximum Borrowing Capacity, Amendment					$ (1,000,000)
Borrego Financing [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Derivative, Fixed Interest Rate					2.31%
Borrego Financing [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	74,000,000											74,000,000		74,000,000		75,000,000
NRG Energy Center Minneapolis LLC, senior secured notes, due 2013, 2017, and 2025 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 112,000,000											$ 112,000,000		$ 112,000,000		121,000,000
NRG Energy Center Minneapolis LLC, senior secured notes, due 2017
Long-term Debt Disclosure
Interest rate	5.95%											5.95%		5.95%
NRG Energy Center Minneapolis LLC, senior secured notes, due 2025
Long-term Debt Disclosure
Interest rate	7.25%											7.25%		7.25%
NRG Borrego I LLC, due 2024
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														2.50%
NRG Borrego I LLC, due 2038
Long-term Debt Disclosure
Variable rate basis
Basis spread on variable rate														5.65%
South Trent Wind LLC, due 2020
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														2.75%
South Trent Wind LLC, due 2020 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 63,000,000											$ 63,000,000		$ 63,000,000		65,000,000
NRG Solar Avra Valley LLC, due 2031
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														1.75%
NRG Solar Avra Valley LLC, due 2031 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	62,000,000											62,000,000		$ 62,000,000		63,000,000
High Desert Facility [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	54,000,000											54,000,000		$ 54,000,000		55,000,000
WCEP Holdings, LLC, due in 2023 [Member]
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														3.00%
WCEP Holdings, LLC, due in 2023 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Percentage of Debt Hedged by Interest Rate Derivatives										90.00%
Derivative, Fixed Interest Rate										4.00%
WCEP Holdings, LLC, due in 2023 [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	46,000,000											46,000,000		$ 46,000,000		46,000,000
WCEP Holdings, LLC, due in 2023 [Member] | Term Loan Facility
Long-term Debt Disclosure
Long-term Debt										$ 53,000,000
Variable rate basis							LIBOR			LIBOR
Basis spread on variable rate							3.00%			4.00%
Repayments of Debt							$ 6,000,000
NRG Roadrunner LLC, due 2031
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														2.01%
NRG Roadrunner LLC, due 2031 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	41,000,000											41,000,000		$ 41,000,000		42,000,000
Kansas South Facility, due 2031 [Member]
Long-term Debt Disclosure
Variable rate basis														6-Month LIBOR
Basis spread on variable rate														2.00%
Kansas South Facility, due 2031 [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	34,000,000											34,000,000		$ 34,000,000		35,000,000
NRG Solar Blythe LLC, due 2028
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														2.75%
NRG Solar Blythe LLC, due 2028 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	22,000,000											22,000,000		$ 22,000,000		22,000,000
PFMG and related subsidiaries, due 2030 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 31,000,000											$ 31,000,000		$ 31,000,000		31,000,000
Interest rate	6.00%											6.00%		6.00%
NRG Energy Center Princeton LLC, due 2017 | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 1,000,000											$ 1,000,000		$ 1,000,000		1,000,000
Interest rate	5.95%											5.95%		5.95%
NRG Yield Revolving Credit Facility
Long-term Debt Disclosure
Line of Credit Facility, Maximum Borrowing Capacity	$ 495,000,000											$ 495,000,000		$ 495,000,000
Line of Credit Facility, Fair Value of Amount Outstanding	267,000,000											267,000,000		267,000,000
NRG Yield Revolving Credit Facility | Letter of Credit [Member]
Long-term Debt Disclosure
Letters of Credit Outstanding, Amount	$ 32,000,000											$ 32,000,000		32,000,000
Alta Wind X and Alta Wind XI, due 2020 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Extinguishment of Debt, Amount														$ 17,000,000
5.375% Senior Notes due in 2024 [Member]
Long-term Debt Disclosure
Interest rate	5.375%											5.375%		5.375%
Senior Notes	$ 500,000,000											$ 500,000,000		$ 500,000,000		500,000,000
5.375% Senior Notes due in 2024 [Member] | NRG Yield Operating LLC [Member]
Long-term Debt Disclosure
Interest rate								5.375%
Proceeds from Issuance of Senior Long-term Debt								$ 500,000,000
Revolving Credit Facility [Member]
Long-term Debt Disclosure
Long-term Debt	267,000,000											267,000,000		$ 267,000,000		0
Variable rate basis														1 month LIBOR
Basis spread on variable rate														2.50%
Alta Wind Asset Management, due 2031 [Member]
Long-term Debt Disclosure
Variable rate basis														3 month LIBOR
Basis spread on variable rate														2.375%
West Holdings Credit Agreement [Member]
Long-term Debt Disclosure
Variable rate basis														1 month LIBOR
Gains (Losses) on Extinguishment of Debt														$ (7,000,000)
West Holdings Credit Agreement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 489,000,000											$ 489,000,000		$ 489,000,000		506,000,000
West Holdings Credit Agreement [Member] | Working Capital Facility [Member]
Long-term Debt Disclosure
Credit Facility, Maximum Borrowing Capacity, Amendment			$ 9,000,000
Alta Wind X, due 2020 [Member]
Long-term Debt Disclosure
Variable rate basis														3 month LIBOR
Basis spread on variable rate														2.00%
Alta Wind XI, due 2020 [Member]
Long-term Debt Disclosure
Variable rate basis														3 month LIBOR
Basis spread on variable rate														2.00%
Alta Wind II, lease financing arrangement, due 2034 [Member] | Non-affiliate
Long-term Debt Disclosure
Interest rate	5.696%											5.696%		5.696%
Alta Wind III, lease financing arrangement, due 2034 [Member] | Non-affiliate
Long-term Debt Disclosure
Interest rate	6.067%											6.067%		6.067%
Alta Wind IV, lease financing arrangement, due 2034 [Member] | Non-affiliate
Long-term Debt Disclosure
Interest rate	5.938%											5.938%		5.938%
Alta Wind V, lease financing arrangement, due 2035 [Member] | Non-affiliate
Long-term Debt Disclosure
Interest rate	6.071%											6.071%		6.071%
Project [Domain] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 3,384,000,000											$ 3,384,000,000		$ 3,384,000,000		3,961,000,000
High Desert Facility, due 2033 [Member]
Long-term Debt Disclosure
Variable rate basis														3-Month LIBOR
Basis spread on variable rate														2.50%
TA - High Desert, due 2023 [Member]
Long-term Debt Disclosure
Interest rate	5.15%											5.15%		5.15%
West Holdings Credit Agreement due 2023 Tranche A [Member]
Long-term Debt Disclosure
Variable rate basis			LIBOR
Basis spread on variable rate			1.625%											1.625%
Proceeds from Issuance of Debt			$ 5,000,000
West Holdings Credit Agreement due 2023 Tranche B [Member]
Long-term Debt Disclosure
Variable rate basis			LIBOR
Basis spread on variable rate			2.25%											2.25%
December 30, 2034 [Member] | Alta Wind I, lease financing arrangement, due 2034 [Member] | Lease Financing Arrangement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	$ 255,000,000											$ 255,000,000		$ 255,000,000		261,000,000
December 30, 2034 [Member] | Alta Wind II, lease financing arrangement, due 2034 [Member] | Lease Financing Arrangement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	200,000,000											200,000,000		200,000,000		205,000,000
December 30, 2034 [Member] | Alta Wind III, lease financing arrangement, due 2034 [Member] | Lease Financing Arrangement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	208,000,000											208,000,000		208,000,000		212,000,000
December 30, 2034 [Member] | Alta Wind IV, lease financing arrangement, due 2034 [Member] | Lease Financing Arrangement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	138,000,000											138,000,000		138,000,000		138,000,000
January 31, 2031 [Member] | Alta Realty Investments, due 2031 [Member] | Notes Payable, Other Payables [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	33,000,000											33,000,000		33,000,000		34,000,000
May 15, 2031 [Member] | Alta Wind Asset Management, due 2031 [Member] | Term Loan Facility | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	19,000,000											19,000,000		19,000,000		20,000,000
March 31, 2020 [Member] | Alta Wind X, due 2020 [Member] | Term Loan Facility | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	0											0		0		300,000,000
March 31, 2020 [Member] | Alta Wind XI, due 2020 [Member] | Term Loan Facility | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	0											0		0		191,000,000
June 30, 2035 [Member] | Alta Wind V, lease financing arrangement, due 2035 [Member] | Lease Financing Arrangement [Member] | Non-affiliate
Long-term Debt Disclosure
Long-term Debt	215,000,000											215,000,000		$ 215,000,000		220,000,000
Minimum [Member] | Alpine [Member]
Long-term Debt Disclosure
Basis spread on variable rate														1.75%
Minimum [Member] | WCEP Holdings, LLC, due in 2023 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Percentage of Debt Hedged by Interest Rate Derivatives							90.00%
Maximum [Member] | Alpine [Member]
Long-term Debt Disclosure
Basis spread on variable rate														2.50%
Maximum [Member] | WCEP Holdings, LLC, due in 2023 [Member] | Interest Rate Swap [Member]
Long-term Debt Disclosure
Percentage of Debt Hedged by Interest Rate Derivatives							100.00%
Avenal | Term Loan Facility
Long-term Debt Disclosure
Debt Instrument, Face Amount				$ 43,000,000
Proceeds from Debt, Net of Issuance Costs				$ 20,000,000
September 1, 2020 through maturity [Member] | West Holdings Credit Agreement due 2023 Tranche A [Member]
Long-term Debt Disclosure
Basis spread on variable rate			1.875%
September 1, 2020 through maturity [Member] | West Holdings Credit Agreement due 2023 Tranche B [Member]
Long-term Debt Disclosure
Basis spread on variable rate			2.50%
December 17, 2014 to December 31, 2018 [Member] | Laredo Ridge Wind, LLC, due in 2026 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis					LIBOR
Basis spread on variable rate					1.875%
January 1, 2019 to December 31, 2023 [Member] | Laredo Ridge Wind, LLC, due in 2026 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis					LIBOR
Basis spread on variable rate					2.125%
January 1, 2024 to March 31, 2028 [Member] | Laredo Ridge Wind, LLC, due in 2026 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis					LIBOR
Basis spread on variable rate					2.375%
November 12, 2014 to December 20, 2018 [Member] | Tapestry Wind LLC due in 2021 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis						LIBOR
Basis spread on variable rate						1.625%
December 21, 2018 to December 31, 2021 [Member] | Tapestry Wind LLC due in 2021 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis						LIBOR
Basis spread on variable rate						1.75%
October 21, 2014 to September 30, 2018 [Member] | Walnut Creek Energy, LLC, due in 2023 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis							LIBOR
Basis spread on variable rate							1.625%
October 1, 2018 to September 30, 2022 [Member] | Walnut Creek Energy, LLC, due in 2023 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis							LIBOR
Basis spread on variable rate							1.75%
October 1, 2022 to May 31, 2023 [Member] | Walnut Creek Energy, LLC, due in 2023 [Member] | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis							LIBOR
Basis spread on variable rate							1.875%
September 22, 2010 to March 18, 2015 [Member] | Avenal | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis				6 month LIBOR
Basis spread on variable rate				2.25%
March 18, 2015 to March 17, 2022 [Member] | Avenal | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis				6 month LIBOR
Basis spread on variable rate				1.75%
March 18, 2022 to March 17, 2027 [Member] | Avenal | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis				6 month LIBOR
Basis spread on variable rate				2.00%
March 18, 2027 through Maturity [Member] | Avenal | Term Loan Facility
Long-term Debt Disclosure
Variable rate basis				6 month LIBOR
Basis spread on variable rate				2.25%
September 1, 2017 to August 31, 2020 [Member] | West Holdings Credit Agreement due 2023 Tranche A [Member]
Long-term Debt Disclosure
Basis spread on variable rate			1.75%
September 1, 2017 to August 31, 2020 [Member] | West Holdings Credit Agreement due 2023 Tranche B [Member]
Long-term Debt Disclosure
Basis spread on variable rate			2.375%
Subsequent Event [Member] | NRG Yield Revolving Credit Facility
Long-term Debt Disclosure
Repayments of Debt											$ 190,000,000
Scenario, Previously Reported [Member]
Long-term Debt Disclosure
Long-term Debt																$ 4,061,000,000
Scenario, Previously Reported [Member] | NRG Yield Revolving Credit Facility
Long-term Debt Disclosure
Line of Credit Facility, Maximum Borrowing Capacity	450,000,000											$ 450,000,000		$ 450,000,000
Financial Institutions [Member] | Alta X and XI TE Holdco [Member]
Long-term Debt Disclosure
Proceeds from Noncontrolling Interests	$ 119,000,000
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Stockholders' Equity (Details)

Stockholders' Equity (Details)	3 Months Ended
	Mar. 31, 2015$ / shares
Stockholders' Equity Attributable to Parent [Abstract]
Dividends Per Class A Common Share	$ 0.39

Segment Reporting (Details)

Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014		Dec. 31, 2014	[4]
Segment Reporting
Total operating revenues	$ 217	$ 173	[1]	$ 397	$ 313	[1]
Cost of operations	67	53		142	113
Depreciation and amortization	59	54	[1]	113	78	[1],[2]
General and administrative — affiliate	3	2		6	4
Business Combination, Acquisition Related Costs	1			1
Operating income	87	64	[1]	135	118	[1]
Income (Loss) from Equity Method Investments	9	14	[1]	10	15	[1]
Other Nonoperating Income (Expense)	0	0	[1]	1	1	[1]
Gains (Losses) on Extinguishment of Debt	(7)	0		(7)	0
Interest Expense	(42)	(33)	[1]	(111)	(59)	[1]
Net Income	47	45	[1],[3]	28	75	[1],[2],[3]
Total Assets	7,044			7,044			$ 6,826
Conventional Generation
Segment Reporting
Total operating revenues	85	87		161	143
Cost of operations	15	16		36	26
Depreciation and amortization	21	34		42	47
Business Combination, Acquisition Related Costs	0			0
Operating income	49	37		83	70
Income (Loss) from Equity Method Investments	4	4		7	7
Other Nonoperating Income (Expense)				1	0
Gains (Losses) on Extinguishment of Debt	(7)			(7)
Interest Expense	(13)	(15)		(25)	(26)
Net Income	33	26		59	51
Total Assets	2,153			2,153
Corporate
Segment Reporting
Total operating revenues	0	0		0	0
Cost of operations	0	0		0	0
Depreciation and amortization	0	0		0	0
Business Combination, Acquisition Related Costs	1			1
Operating income	(4)	(2)		(7)	(4)
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	(11)	(5)		(23)	(6)
Net Income	(15)	(7)		(30)	(10)
Total Assets	234			234
Thermal [Member]
Segment Reporting
Total operating revenues	42	43		89	108
Cost of operations	31	30		65	76
Depreciation and amortization	4	5		9	9
Business Combination, Acquisition Related Costs	0			0
Operating income	7	8		15	23
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	(2)	(2)		(4)	(4)
Net Income	5	6		11	19
Total Assets	434			434
Renewables
Segment Reporting
Total operating revenues	90	43		147	62
Cost of operations	21	7		41	11
Depreciation and amortization	34	15		62	22
Business Combination, Acquisition Related Costs	0			0
Operating income	35	21		44	29
Income (Loss) from Equity Method Investments	5	10		3	8
Other Nonoperating Income (Expense)				0	1
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	(16)	(11)		(59)	(23)
Net Income	24	20		(12)	15
Total Assets	4,223			4,223
Affiliated Entity [Member]
Segment Reporting
General and administrative — affiliate	3	2	[1]	6	4	[1]
Affiliated Entity [Member] | Conventional Generation
Segment Reporting
General and administrative — affiliate	0	0		0	0
Affiliated Entity [Member] | Corporate
Segment Reporting
General and administrative — affiliate	3	2		6	4
Affiliated Entity [Member] | Thermal [Member]
Segment Reporting
General and administrative — affiliate	0	0		0	0
Affiliated Entity [Member] | Renewables
Segment Reporting
General and administrative — affiliate	$ 0	$ 0		$ 0	$ 0
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[4]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014		Dec. 31, 2014
Related Party Transaction
General and administrative — affiliate	$ 3	$ 2		$ 6	$ 4
Management Services Agreement with NRG
Related Party Transaction
Management Services Fee, Increase				1
Scenario, Plan [Member] | Management Services Agreement with NRG
Related Party Transaction
Management Services Fee, Annual				7
Affiliated Entity [Member]
Related Party Transaction
General and administrative — affiliate	3	$ 2	[1]	6	4	[1]
NRG [Member]
Related Party Transaction
Due to Related Parties	3			3
Thermal [Member] | NRG [Member]
Related Party Transaction
Due to Related Parties	28			28			$ 22
Related Party Transaction, Expenses from Transactions with Related Party				15	14
Marsh Landing [Member] | GenOn Energy Services LLC [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party				9	9
Marsh Landing [Member] | GenOn Energy Services LLC [Member]
Related Party Transaction
Due to Related Parties	$ 0			0			$ 4
Gen Conn Energy LLC [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party				$ 2	$ 3
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan40

Condensed Consolidating Financial Information CP Income Statement (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Condensed Income Statements, Captions [Line Items]
Total operating revenues	$ 217	$ 173	[1]	$ 397	$ 313	[1]
Operating Costs and Expenses [Abstract]
Cost of operations	67	53	[1]	142	113	[1]
Depreciation, Depletion and Amortization	59	54	[1]	113	78	[1],[2]
General and administrative — affiliate	3	2		6	4
Business Combination, Integration Related Costs	1	0	[1]	1	0	[1]
Costs and Expenses	130	109	[1]	262	195	[1]
Operating Income (Loss)	87	64	[1]	135	118	[1]
Costs and Expenses [Abstract]
Equity in Earnings of Consolidated Subsidiaries	0	0		0	0
Income (Loss) from Equity Method Investments	9	14	[1]	10	15	[1]
Other Nonoperating Income (Expense)	0	0	[1]	1	1	[1]
Gains (Losses) on Extinguishment of Debt	(7)	0		(7)	0
Interest Expense	(42)	(33)	[1]	(111)	(59)	[1]
Total other expense, net	(40)	(19)	[1]	(107)	(43)	[1]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	47	45	[1],[3]	28	75	[1],[2],[3]
Net Income (Loss) Attributable to Parent	40			21
NRG Yield LLC [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	0	0		0	$ 0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0
Depreciation, Depletion and Amortization	0	0		0
General and administrative — affiliate	0	0		0	$ 0
Business Combination, Integration Related Costs	0			0
Costs and Expenses	0	0		0	0
Operating Income (Loss)	0	0		0	0
Costs and Expenses [Abstract]
Equity in Earnings of Consolidated Subsidiaries	40	45		21	75
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	0	0		0	0
Total other expense, net	40	45		21	75
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	40	45		21	75
Net Income (Loss) Attributable to Parent	40			21
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	5	5		10	12
Operating Costs and Expenses [Abstract]
Cost of operations	3	3		7	8
Depreciation, Depletion and Amortization	1	1		2	2
General and administrative — affiliate	0	0		0	0
Business Combination, Integration Related Costs	0			0
Costs and Expenses	4	4		9	10
Operating Income (Loss)	1	1		1	2
Costs and Expenses [Abstract]
Equity in Earnings of Consolidated Subsidiaries	6	2		(19)	2
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	0	0		0	0
Total other expense, net	6	2		(19)	2
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	7	3		(18)	4
Net Income (Loss) Attributable to Parent	7			(18)
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	213	168		379	301
Operating Costs and Expenses [Abstract]
Cost of operations	64	50		135	105
Depreciation, Depletion and Amortization	58	53		111	76
General and administrative — affiliate	0	0		0	0
Business Combination, Integration Related Costs	0			0
Costs and Expenses	122	103		246	181
Operating Income (Loss)	91	65		133	120
Costs and Expenses [Abstract]
Equity in Earnings of Consolidated Subsidiaries	0	0		0	0
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				1	1
Gains (Losses) on Extinguishment of Debt	(7)			(7)
Interest Expense	(30)	(28)		(87)	(53)
Total other expense, net	(37)	(28)		(93)	(52)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	54	37		40	68
Net Income (Loss) Attributable to Parent	58			44
NRG Yield Operating LLC [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	(1)	0		8	0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0	0
Depreciation, Depletion and Amortization	0	0		0	0
General and administrative — affiliate	3	2		6	4
Business Combination, Integration Related Costs	1			1
Costs and Expenses	4	2		7	4
Operating Income (Loss)	(5)	(2)		1	(4)
Costs and Expenses [Abstract]
Equity in Earnings of Consolidated Subsidiaries	59	38		45	70
Income (Loss) from Equity Method Investments	9	14		10	15
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	(12)	(5)		(24)	(6)
Total other expense, net	56	47		31	79
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	51	45		32	75
Net Income (Loss) Attributable to Parent	40			21
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	0	0		0	0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0	0
Depreciation, Depletion and Amortization	0	0		0	0
General and administrative — affiliate	0	0		0	0
Business Combination, Integration Related Costs	0			0
Costs and Expenses	0	0		0	0
Operating Income (Loss)	0	0		0	0
Costs and Expenses [Abstract]
Equity in Earnings of Consolidated Subsidiaries	(105)	(85)		(47)	(147)
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Gains (Losses) on Extinguishment of Debt	0			0
Interest Expense	0	0		0	0
Total other expense, net	(105)	(85)		(47)	(147)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(105)	$ (85)		(47)	$ (147)
Net Income (Loss) Attributable to Parent	$ (105)			$ (47)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan41

Condensed Consolidating Financial Information CP Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 47	$ 45	[1],[2]	$ 28	$ 75	[1],[2],[3]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	25	(22)	[2]	0	(34)	[2]
Other Comprehensive Income (Loss), Net of Tax	25	(22)	[2]	0	(34)	[2]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	72	23		28	41
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	7	0		7	0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	65	23		21	41
NRG Yield LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	40	45		21	75
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	25	(22)			(34)
Other Comprehensive Income (Loss), Net of Tax	25	(22)			(34)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	65	23		21	41
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0			0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	65			21
Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	7	3		(18)	4
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	1	0			0
Other Comprehensive Income (Loss), Net of Tax	1	0			0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	8	3		(18)	4
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0			0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	8			(18)
Non-Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	54	37		40	68
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	24	(21)			(32)
Other Comprehensive Income (Loss), Net of Tax	24	(21)			(32)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	78	16		40	36
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	(4)			(4)
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	82			44
NRG Yield Operating LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	51	45		32	75
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	25	(22)			(34)
Other Comprehensive Income (Loss), Net of Tax	25	(22)			(34)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	76	23		32	41
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	11			11
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	65			21
Consolidation, Eliminations [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(105)	(85)		(47)	(147)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(50)	43			66
Other Comprehensive Income (Loss), Net of Tax	(50)	43			66
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(155)	$ (42)		(47)	$ (81)
Comprehensive Income (Loss), Net of Tax, Attributable to Noncontrolling Interest	0			0
Comprehensive Income (Loss), Net of Tax, Attributable to Parent	$ (155)			$ (47)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan42

Condensed Consolidating Financial Information CP Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014		Jun. 30, 2014		Dec. 31, 2013
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	$ 407	$ 214	[1]
Cash and Cash Equivalents, at Carrying Value	281	406	[1]	$ 108	[2]	$ 59	[2]
Restricted Cash and Cash Equivalents, Current	38	45	[1]
Accounts Receivable, Net, Current	98	85	[1]
Due from Affiliate, Current	2	0	[1]
Inventory, Net	29	27	[1]
Derivative Asset	4	0	[1]
Notes, Loans and Financing Receivable, Net, Current	7	6	[1]
Prepaid Expense and Other Assets, Current	19	21	[1]
Assets, Current	478	590	[1]
Property, Plant and Equipment, Net	4,478	4,466	[1]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Equity Method Investments	549	227	[1]
Notes, Loans and Financing Receivable, Net, Noncurrent	13	15	[1]
Finite-Lived Intangible Assets, Net	1,389	1,423	[1]
Derivative Asset, Noncurrent	4
Other Assets, Noncurrent	133	103	[1]
Other Assets	2,088	1,770	[1]
Assets	7,044	6,826	[1]
Accounts Payable, Current	23	20	[1]
Due to Affiliate, Current	60	45	[1]
Derivative Liability, Current	43	48	[1]
Accrued Expenses and Other Current Liabilities	37	61	[1]
Liabilities, Current	570	388	[1]
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	3,744	4,247	[1]
Due to Affiliate, Noncurrent	618	337	[1]
Derivative Liability, Noncurrent	44	69	[1]
Other Liabilities, Noncurrent	52	49	[1]
Liabilities, Noncurrent	4,458	4,702	[1]
Liabilities	$ 5,028	$ 5,090	[1]
Commitments and Contingencies
Members' Capital	$ 1,729	$ 1,609	[1]
Retained Earnings (Accumulated Deficit)	145	185	[1]
Members' Equity Attributable to Noncontrolling Interest	200
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)	[1]
Members' Equity	2,016	1,736	[1]
Liabilities and Equity	7,044	6,826	[1]
NRG Yield LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	0	0
Cash and Cash Equivalents, at Carrying Value	220	328		54		3
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	0	0
Due from Affiliate, Current	0	(256)
Inventory, Net	0	0
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	0	0
Assets, Current	220	72
Property, Plant and Equipment, Net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	1,946	1,664
Equity Method Investments	0	0
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	0	0
Derivative Asset, Noncurrent	0
Other Assets, Noncurrent	0	0
Other Assets	1,946	1,664
Assets	2,166	1,736
Accounts Payable, Current	0	0
Due to Affiliate, Current	150	0
Derivative Liability, Current	0	0
Accrued Expenses and Other Current Liabilities	0	0
Liabilities, Current	150	0
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	0	0
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	0	0
Liabilities, Noncurrent	0	0
Liabilities	150	0
Members' Capital	1,729	1,609
Retained Earnings (Accumulated Deficit)	145	185
Members' Equity Attributable to Noncontrolling Interest	200
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)
Members' Equity	2,016	1,736
Liabilities and Equity	2,166	1,736
Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	0	0
Cash and Cash Equivalents, at Carrying Value	0	0
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	2	3
Due from Affiliate, Current	23	17
Inventory, Net	2	1
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	1	1
Assets, Current	28	22
Property, Plant and Equipment, Net	63	56
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	574	585
Equity Method Investments	18	0
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	57	58
Derivative Asset, Noncurrent	0
Other Assets, Noncurrent	0	0
Other Assets	649	643
Assets	740	721
Accounts Payable, Current	1	1
Due to Affiliate, Current	10	8
Derivative Liability, Current	0	0
Accrued Expenses and Other Current Liabilities	2	2
Liabilities, Current	13	11
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	0	0
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	1	0
Liabilities, Noncurrent	1	0
Liabilities	14	11
Members' Capital	780	747
Retained Earnings (Accumulated Deficit)	(51)	(34)
Members' Equity Attributable to Noncontrolling Interest	0
Accumulated Other Comprehensive Income (Loss), Net of Tax	(3)	(3)
Members' Equity	726	710
Liabilities and Equity	740	721
Non-Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	217	214
Cash and Cash Equivalents, at Carrying Value	61	78		54		36
Restricted Cash and Cash Equivalents, Current	38	45
Accounts Receivable, Net, Current	96	82
Due from Affiliate, Current	65	66
Inventory, Net	27	26
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	7	6
Prepaid Expense and Other Assets, Current	18	20
Assets, Current	312	323
Property, Plant and Equipment, Net	4,415	4,410
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Equity Method Investments	0	0
Notes, Loans and Financing Receivable, Net, Noncurrent	13	15
Finite-Lived Intangible Assets, Net	1,332	1,365
Derivative Asset, Noncurrent	4
Other Assets, Noncurrent	124	93
Other Assets	1,473	1,475
Assets	6,200	6,208
Accounts Payable, Current	22	19
Due to Affiliate, Current	99	99
Derivative Liability, Current	42	48
Accrued Expenses and Other Current Liabilities	18	43
Liabilities, Current	398	423
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	3,167	3,747
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	44	69
Other Liabilities, Noncurrent	51	49
Liabilities, Noncurrent	3,262	3,865
Liabilities	3,660	4,288
Members' Capital	2,414	1,848
Retained Earnings (Accumulated Deficit)	97	113
Members' Equity Attributable to Noncontrolling Interest	70
Accumulated Other Comprehensive Income (Loss), Net of Tax	(41)	(41)
Members' Equity	2,540	1,920
Liabilities and Equity	6,200	6,208
NRG Yield Operating LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	190	0
Cash and Cash Equivalents, at Carrying Value	0	0		$ 0		$ 20
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	0	0
Due from Affiliate, Current	158	268
Inventory, Net	0	0
Derivative Asset	4
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	0	0
Assets, Current	162	268
Property, Plant and Equipment, Net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	2,692	2,045
Equity Method Investments	531	227
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	0	0
Derivative Asset, Noncurrent	0
Other Assets, Noncurrent	9	10
Other Assets	3,232	2,282
Assets	3,394	2,550
Accounts Payable, Current	0	0
Due to Affiliate, Current	45	33
Derivative Liability, Current	1	0
Accrued Expenses and Other Current Liabilities	17	16
Liabilities, Current	253	49
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	577	500
Due to Affiliate, Noncurrent	618	337
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	0	0
Liabilities, Noncurrent	1,195	837
Liabilities	1,448	886
Members' Capital	1,694	1,542
Retained Earnings (Accumulated Deficit)	110	180
Members' Equity Attributable to Noncontrolling Interest	200
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)
Members' Equity	1,946	1,664
Liabilities and Equity	3,394	2,550
Consolidation, Eliminations [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	0	0
Cash and Cash Equivalents, at Carrying Value	0	0
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	0	0
Due from Affiliate, Current	(244)	(95)
Inventory, Net	0	0
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	0	0
Assets, Current	(244)	(95)
Property, Plant and Equipment, Net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	(5,212)	(4,294)
Equity Method Investments	0	0
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	0	0
Derivative Asset, Noncurrent	0
Other Assets, Noncurrent	0	0
Other Assets	(5,212)	(4,294)
Assets	(5,456)	(4,389)
Accounts Payable, Current	0	0
Due to Affiliate, Current	(244)	(95)
Derivative Liability, Current	0	0
Accrued Expenses and Other Current Liabilities	0	0
Liabilities, Current	(244)	(95)
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	0	0
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	0	0
Liabilities, Noncurrent	0	0
Liabilities	(244)	(95)
Members' Capital	(4,888)	(4,137)
Retained Earnings (Accumulated Deficit)	(156)	(259)
Members' Equity Attributable to Noncontrolling Interest	(270)
Accumulated Other Comprehensive Income (Loss), Net of Tax	102	102
Members' Equity	(5,212)	(4,294)
Liabilities and Equity	$ (5,456)	$ (4,389)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan43

Condensed Consolidating Financial Information CP Cash Flows (Details) - USD ($) $ in Millions	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014		Dec. 31, 2014		Dec. 31, 2013
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			$ 88	$ 75	[1]
Intercompany (Payments to) Receipts from Consolidated Subsidiaries			0
Acquisition of businesses, net of cash acquired			(37)	0
Payments to Acquire Property, Plant, and Equipment			(8)	(29)	[1]
Increase (Decrease) in Restricted Cash			7	49	[1]
Increase (Decrease) in Notes Receivable			3	5	[1]
Proceeds from Renewable Energy Grants			0	137	[1]
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			(313)	(15)	[1]
Payments for (Proceeds from) Other Investing Activities			0	11	[1]
Net Cash Provided by (Used in) Investing Activities			(837)	(178)	[1]
Proceeds from Payments to Intercompany Loans			0	0
Investment in Consolidated Subsidiaries			0
Proceeds from Noncontrolling Interests			119	0
Proceeds from Issuance of Common Stock			600	0
Payments of Dividends			(61)	(44)	[1]
Proceeds from Issuance of Long-term Debt			287	41	[1]
Proceeds from Related Party Debt			281	337	[1]
Payments of Debt Issuance Costs			(4)	(5)
Proceeds from (Repayments of) Debt			(598)	(154)
Net Cash Provided by (Used in) Financing Activities			624	152	[1]
Cash and Cash Equivalents, Period Increase (Decrease)			(125)	49	[1]
Cash and Cash Equivalents, at Carrying Value	$ 108	[1]	281	108	[1]	$ 406	[2]	$ 59	[1]
NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			(23)	46
Intercompany (Payments to) Receipts from Consolidated Subsidiaries			(517)
Acquisition of businesses, net of cash acquired			0	0
Payments to Acquire Property, Plant, and Equipment			0	0
Increase (Decrease) in Restricted Cash			0	0
Increase (Decrease) in Notes Receivable			0	0
Proceeds from Renewable Energy Grants				0
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			0	0
Payments for (Proceeds from) Other Investing Activities				0
Net Cash Provided by (Used in) Investing Activities			(517)	0
Proceeds from Payments to Intercompany Loans			(107)	49
Investment in Consolidated Subsidiaries			0
Proceeds from Noncontrolling Interests			0
Proceeds from Issuance of Common Stock			600
Payments of Dividends			(61)	(44)
Proceeds from Issuance of Long-term Debt			0	0
Proceeds from Related Party Debt			0	0
Payments of Debt Issuance Costs			0
Proceeds from (Repayments of) Debt			0	0
Net Cash Provided by (Used in) Financing Activities			432	5
Cash and Cash Equivalents, Period Increase (Decrease)			(108)	51
Cash and Cash Equivalents, at Carrying Value	54		220	54		328		3
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			10
Intercompany (Payments to) Receipts from Consolidated Subsidiaries			0
Acquisition of businesses, net of cash acquired			0
Payments to Acquire Property, Plant, and Equipment			0
Increase (Decrease) in Restricted Cash			0
Increase (Decrease) in Notes Receivable			0
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			(4)
Net Cash Provided by (Used in) Investing Activities			(4)
Proceeds from Payments to Intercompany Loans			(6)
Investment in Consolidated Subsidiaries			0
Proceeds from Noncontrolling Interests			0
Proceeds from Issuance of Common Stock			0
Payments of Dividends			0
Proceeds from Issuance of Long-term Debt			0
Proceeds from Related Party Debt			0
Payments of Debt Issuance Costs			0
Proceeds from (Repayments of) Debt			0
Net Cash Provided by (Used in) Financing Activities			(6)
Cash and Cash Equivalents, Period Increase (Decrease)			0
Cash and Cash Equivalents, at Carrying Value			0			0
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			69	(33)
Intercompany (Payments to) Receipts from Consolidated Subsidiaries			0
Acquisition of businesses, net of cash acquired			0	21
Payments to Acquire Property, Plant, and Equipment			(8)	(29)
Increase (Decrease) in Restricted Cash			(7)	(49)
Increase (Decrease) in Notes Receivable			3	3
Proceeds from Renewable Energy Grants				137
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			0	0
Payments for (Proceeds from) Other Investing Activities				11
Net Cash Provided by (Used in) Investing Activities			2	192
Proceeds from Payments to Intercompany Loans			0	0
Investment in Consolidated Subsidiaries			491
Proceeds from Noncontrolling Interests			0
Proceeds from Issuance of Common Stock			0
Payments of Dividends			0	0
Proceeds from Issuance of Long-term Debt			5	41
Proceeds from Related Party Debt			0	0
Payments of Debt Issuance Costs			(4)
Proceeds from (Repayments of) Debt			(580)	(154)
Net Cash Provided by (Used in) Financing Activities			(88)	(141)
Cash and Cash Equivalents, Period Increase (Decrease)			(17)	18
Cash and Cash Equivalents, at Carrying Value	54		61	54		78		36
NRG Yield Operating LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			32	62
Intercompany (Payments to) Receipts from Consolidated Subsidiaries			517
Acquisition of businesses, net of cash acquired			(37)	(357)
Payments to Acquire Property, Plant, and Equipment			0	0
Increase (Decrease) in Restricted Cash			0	0
Increase (Decrease) in Notes Receivable			0	2
Proceeds from Renewable Energy Grants				0
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			(309)	(15)
Payments for (Proceeds from) Other Investing Activities				0
Net Cash Provided by (Used in) Investing Activities			(318)	(370)
Proceeds from Payments to Intercompany Loans			113	(49)
Investment in Consolidated Subsidiaries			(491)
Proceeds from Noncontrolling Interests			119
Proceeds from Issuance of Common Stock			0
Payments of Dividends			0	0
Proceeds from Issuance of Long-term Debt			282	0
Proceeds from Related Party Debt			281	337
Payments of Debt Issuance Costs			0
Proceeds from (Repayments of) Debt			(18)	0
Net Cash Provided by (Used in) Financing Activities			286	288
Cash and Cash Equivalents, Period Increase (Decrease)			0	(20)
Cash and Cash Equivalents, at Carrying Value	0		0	0		0		$ 20
Consolidation, Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value			0			$ 0
Drop-down Acquisition [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired	$ (357)		(489)	$ (336)
Drop-down Acquisition [Member] | NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			0
Drop-down Acquisition [Member] | Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			0
Drop-down Acquisition [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			0
Drop-down Acquisition [Member] | NRG Yield Operating LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			$ (489)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan44

Condensed Consolidating Financial Information PP Income Statement (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Condensed Income Statements, Captions [Line Items]
Total operating revenues	$ 217	$ 173	[1]	$ 397	$ 313	[1]
Operating Costs and Expenses [Abstract]
Cost of operations	67	53	[1]	142	113	[1]
Depreciation, Depletion and Amortization	59	54	[1]	113	78	[1],[2]
General and administrative — affiliate	3	2		6	4
Costs and Expenses	130	109	[1]	262	195	[1]
Operating Income (Loss)	87	64	[1]	135	118	[1]
Equity in Earnings of Consolidated Subsidiaries	0	0		0	0
Income (Loss) from Equity Method Investments	9	14	[1]	10	15	[1]
Other Nonoperating Income (Expense)	0	0	[1]	1	1	[1]
Interest Expense	(42)	(33)	[1]	(111)	(59)	[1]
Nonoperating Income (Expense)	(40)	(19)	[1]	(107)	(43)	[1]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	47	45	[1],[3]	28	75	[1],[2],[3]
NRG Yield LLC [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	0	0		0	$ 0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0
Depreciation, Depletion and Amortization	0	0		0
General and administrative — affiliate	0	0		0	$ 0
Costs and Expenses	0	0		0	0
Operating Income (Loss)	0	0		0	0
Equity in Earnings of Consolidated Subsidiaries	40	45		21	75
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Interest Expense	0	0		0	0
Nonoperating Income (Expense)	40	45		21	75
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	40	45		21	75
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	5	5		10	12
Operating Costs and Expenses [Abstract]
Cost of operations	3	3		7	8
Depreciation, Depletion and Amortization	1	1		2	2
General and administrative — affiliate	0	0		0	0
Costs and Expenses	4	4		9	10
Operating Income (Loss)	1	1		1	2
Equity in Earnings of Consolidated Subsidiaries	6	2		(19)	2
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Interest Expense	0	0		0	0
Nonoperating Income (Expense)	6	2		(19)	2
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	7	3		(18)	4
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	213	168		379	301
Operating Costs and Expenses [Abstract]
Cost of operations	64	50		135	105
Depreciation, Depletion and Amortization	58	53		111	76
General and administrative — affiliate	0	0		0	0
Costs and Expenses	122	103		246	181
Operating Income (Loss)	91	65		133	120
Equity in Earnings of Consolidated Subsidiaries	0	0		0	0
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				1	1
Interest Expense	(30)	(28)		(87)	(53)
Nonoperating Income (Expense)	(37)	(28)		(93)	(52)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	54	37		40	68
NRG Yield Operating LLC [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	(1)	0		8	0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0	0
Depreciation, Depletion and Amortization	0	0		0	0
General and administrative — affiliate	3	2		6	4
Costs and Expenses	4	2		7	4
Operating Income (Loss)	(5)	(2)		1	(4)
Equity in Earnings of Consolidated Subsidiaries	59	38		45	70
Income (Loss) from Equity Method Investments	9	14		10	15
Other Nonoperating Income (Expense)				0	0
Interest Expense	(12)	(5)		(24)	(6)
Nonoperating Income (Expense)	56	47		31	79
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	51	45		32	75
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues	0	0		0	0
Operating Costs and Expenses [Abstract]
Cost of operations	0	0		0	0
Depreciation, Depletion and Amortization	0	0		0	0
General and administrative — affiliate	0	0		0	0
Costs and Expenses	0	0		0	0
Operating Income (Loss)	0	0		0	0
Equity in Earnings of Consolidated Subsidiaries	(105)	(85)		(47)	(147)
Income (Loss) from Equity Method Investments	0	0		0	0
Other Nonoperating Income (Expense)				0	0
Interest Expense	0	0		0	0
Nonoperating Income (Expense)	(105)	(85)		(47)	(147)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ (105)	$ (85)		$ (47)	$ (147)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan45

Condensed Consolidating Financial Information PP Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	$ 47	$ 45	[1],[2]	$ 28	$ 75	[1],[2],[3]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	25	(22)	[2]	0	(34)	[2]
Other Comprehensive Income (Loss), Net of Tax	25	(22)	[2]	0	(34)	[2]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	72	23		28	41
NRG Yield LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	40	45		21	75
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	25	(22)			(34)
Other Comprehensive Income (Loss), Net of Tax	25	(22)			(34)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	65	23		21	41
Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	7	3		(18)	4
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	1	0			0
Other Comprehensive Income (Loss), Net of Tax	1	0			0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	8	3		(18)	4
Non-Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	54	37		40	68
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	24	(21)			(32)
Other Comprehensive Income (Loss), Net of Tax	24	(21)			(32)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	78	16		40	36
NRG Yield Operating LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	51	45		32	75
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	25	(22)			(34)
Other Comprehensive Income (Loss), Net of Tax	25	(22)			(34)
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	76	23		32	41
Consolidation, Eliminations [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	(105)	(85)		(47)	(147)
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(50)	43			66
Other Comprehensive Income (Loss), Net of Tax	(50)	43			66
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	$ (155)	$ (42)		$ (47)	$ (81)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[3]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan46

Condensed Consolidating Financial Information PP Balance Sheet (Details) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014		Jun. 30, 2014		Dec. 31, 2013
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	$ 407	$ 214	[1]
Cash and Cash Equivalents, at Carrying Value	281	406	[1]	$ 108	[2]	$ 59	[2]
Restricted Cash and Cash Equivalents, Current	38	45	[1]
Accounts Receivable, Net, Current	98	85	[1]
Due from Affiliate, Current	2	0	[1]
Inventory, Net	29	27	[1]
Derivative Asset	4	0	[1]
Notes, Loans and Financing Receivable, Net, Current	7	6	[1]
Prepaid Expense and Other Assets, Current	19	21	[1]
Assets, Current	478	590	[1]
Property, Plant and Equipment, Net	4,478	4,466	[1]
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Equity Method Investments	549	227	[1]
Notes, Loans and Financing Receivable, Net, Noncurrent	13	15	[1]
Finite-Lived Intangible Assets, Net	1,389	1,423	[1]
Derivative Instruments and Hedges, Noncurrent	4	2	[1]
Other Assets, Noncurrent	133	103	[1]
Other Assets	2,088	1,770	[1]
Assets	7,044	6,826	[1]
Accounts Payable, Current	23	20	[1]
Due to Affiliate, Current	60	45	[1]
Derivative Liability, Current	43	48	[1]
Accrued Expenses and Other Current Liabilities	37	61	[1]
Liabilities, Current	570	388	[1]
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	3,744	4,247	[1]
Due to Affiliate, Noncurrent	618	337	[1]
Derivative Liability, Noncurrent	44	69	[1]
Other Liabilities, Noncurrent	52	49	[1]
Liabilities, Noncurrent	4,458	4,702	[1]
Liabilities	$ 5,028	$ 5,090	[1]
Commitments and Contingencies
Members' Capital	$ 1,729	$ 1,609	[1]
Retained Earnings (Accumulated Deficit)	145	185	[1]
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)	[1]
Members' Equity	2,016	1,736	[1]
Liabilities and Equity	7,044	6,826	[1]
NRG Yield LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	0	0
Cash and Cash Equivalents, at Carrying Value	220	328		54		3
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	0	0
Due from Affiliate, Current	0	(256)
Inventory, Net	0	0
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	0	0
Assets, Current	220	72
Property, Plant and Equipment, Net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	1,946	1,664
Equity Method Investments	0	0
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	0	0
Derivative Instruments and Hedges, Noncurrent		0
Other Assets, Noncurrent	0	0
Other Assets	1,946	1,664
Assets	2,166	1,736
Accounts Payable, Current	0	0
Due to Affiliate, Current	150	0
Derivative Liability, Current	0	0
Accrued Expenses and Other Current Liabilities	0	0
Liabilities, Current	150	0
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	0	0
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	0	0
Liabilities, Noncurrent	0	0
Liabilities	150	0
Members' Capital	1,729	1,609
Retained Earnings (Accumulated Deficit)	145	185
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)
Members' Equity	2,016	1,736
Liabilities and Equity	2,166	1,736
Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	0	0
Cash and Cash Equivalents, at Carrying Value	0	0
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	2	3
Due from Affiliate, Current	23	17
Inventory, Net	2	1
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	1	1
Assets, Current	28	22
Property, Plant and Equipment, Net	63	56
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	574	585
Equity Method Investments	18	0
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	57	58
Derivative Instruments and Hedges, Noncurrent		0
Other Assets, Noncurrent	0	0
Other Assets	649	643
Assets	740	721
Accounts Payable, Current	1	1
Due to Affiliate, Current	10	8
Derivative Liability, Current	0	0
Accrued Expenses and Other Current Liabilities	2	2
Liabilities, Current	13	11
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	0	0
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	1	0
Liabilities, Noncurrent	1	0
Liabilities	14	11
Members' Capital	780	747
Retained Earnings (Accumulated Deficit)	(51)	(34)
Accumulated Other Comprehensive Income (Loss), Net of Tax	(3)	(3)
Members' Equity	726	710
Liabilities and Equity	740	721
Non-Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	217	214
Cash and Cash Equivalents, at Carrying Value	61	78		54		36
Restricted Cash and Cash Equivalents, Current	38	45
Accounts Receivable, Net, Current	96	82
Due from Affiliate, Current	65	66
Inventory, Net	27	26
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	7	6
Prepaid Expense and Other Assets, Current	18	20
Assets, Current	312	323
Property, Plant and Equipment, Net	4,415	4,410
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	0	0
Equity Method Investments	0	0
Notes, Loans and Financing Receivable, Net, Noncurrent	13	15
Finite-Lived Intangible Assets, Net	1,332	1,365
Derivative Instruments and Hedges, Noncurrent		2
Other Assets, Noncurrent	124	93
Other Assets	1,473	1,475
Assets	6,200	6,208
Accounts Payable, Current	22	19
Due to Affiliate, Current	99	99
Derivative Liability, Current	42	48
Accrued Expenses and Other Current Liabilities	18	43
Liabilities, Current	398	423
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	3,167	3,747
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	44	69
Other Liabilities, Noncurrent	51	49
Liabilities, Noncurrent	3,262	3,865
Liabilities	3,660	4,288
Members' Capital	2,414	1,848
Retained Earnings (Accumulated Deficit)	97	113
Accumulated Other Comprehensive Income (Loss), Net of Tax	(41)	(41)
Members' Equity	2,540	1,920
Liabilities and Equity	6,200	6,208
NRG Yield Operating LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	190	0
Cash and Cash Equivalents, at Carrying Value	0	0		$ 0		$ 20
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	0	0
Due from Affiliate, Current	158	268
Inventory, Net	0	0
Derivative Asset	4
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	0	0
Assets, Current	162	268
Property, Plant and Equipment, Net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	2,692	2,045
Equity Method Investments	531	227
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	0	0
Derivative Instruments and Hedges, Noncurrent		0
Other Assets, Noncurrent	9	10
Other Assets	3,232	2,282
Assets	3,394	2,550
Accounts Payable, Current	0	0
Due to Affiliate, Current	45	33
Derivative Liability, Current	1	0
Accrued Expenses and Other Current Liabilities	17	16
Liabilities, Current	253	49
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	577	500
Due to Affiliate, Noncurrent	618	337
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	0	0
Liabilities, Noncurrent	1,195	837
Liabilities	1,448	886
Members' Capital	1,694	1,542
Retained Earnings (Accumulated Deficit)	110	180
Accumulated Other Comprehensive Income (Loss), Net of Tax	(58)	(58)
Members' Equity	1,946	1,664
Liabilities and Equity	3,394	2,550
Consolidation, Eliminations [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Current portion of long-term debt	0	0
Cash and Cash Equivalents, at Carrying Value	0	0
Restricted Cash and Cash Equivalents, Current	0	0
Accounts Receivable, Net, Current	0	0
Due from Affiliate, Current	(244)	(95)
Inventory, Net	0	0
Derivative Asset	0
Notes, Loans and Financing Receivable, Net, Current	0	0
Prepaid Expense and Other Assets, Current	0	0
Assets, Current	(244)	(95)
Property, Plant and Equipment, Net	0	0
Investments in and Advance to Affiliates, Subsidiaries, Associates, and Joint Ventures	(5,212)	(4,294)
Equity Method Investments	0	0
Notes, Loans and Financing Receivable, Net, Noncurrent	0	0
Finite-Lived Intangible Assets, Net	0	0
Derivative Instruments and Hedges, Noncurrent		0
Other Assets, Noncurrent	0	0
Other Assets	(5,212)	(4,294)
Assets	(5,456)	(4,389)
Accounts Payable, Current	0	0
Due to Affiliate, Current	(244)	(95)
Derivative Liability, Current	0	0
Accrued Expenses and Other Current Liabilities	0	0
Liabilities, Current	(244)	(95)
Liabilities, Noncurrent [Abstract]
Long-term Debt and Capital Lease Obligations	0	0
Due to Affiliate, Noncurrent	0	0
Derivative Liability, Noncurrent	0	0
Other Liabilities, Noncurrent	0	0
Liabilities, Noncurrent	0	0
Liabilities	(244)	(95)
Members' Capital	(4,888)	(4,137)
Retained Earnings (Accumulated Deficit)	(156)	(259)
Accumulated Other Comprehensive Income (Loss), Net of Tax	102	102
Members' Equity	(5,212)	(4,294)
Liabilities and Equity	$ (5,456)	$ (4,389)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan47

Condensed Consolidating Financial Information PP Cash Flows (Details) - USD ($) $ in Millions	Jun. 30, 2014		Jun. 30, 2015	Jun. 30, 2014		Dec. 31, 2014		Dec. 31, 2013
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			$ 88	$ 75	[1]
Acquisition of businesses, net of cash acquired			(37)	0
Payments to Acquire Property, Plant, and Equipment			(8)	(29)	[1]
Increase (Decrease) in Restricted Cash			7	49	[1]
Increase (Decrease) in Notes Receivable			3	5	[1]
Proceeds from Renewable Energy Grants			0	137	[1]
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			(313)	(15)	[1]
Payments for (Proceeds from) Other Investing Activities			0	11	[1]
Net Cash Provided by (Used in) Investing Activities			(837)	(178)	[1]
Proceeds from Contributions from Parent				2
Payments of Capital Distribution				(25)
Proceeds from Payments to Intercompany Loans			0	0
Payments of Dividends			(61)	(44)	[1]
Proceeds from Issuance of Long-term Debt			287	41	[1]
Proceeds from (Repayments of) Debt			(598)	(154)
Proceeds from Related Party Debt			281	337	[1]
Payments of Financing Costs				(5)
Net Cash Provided by (Used in) Financing Activities			624	152	[1]
Cash and Cash Equivalents, Period Increase (Decrease)			(125)	49	[1]
Cash and Cash Equivalents, at Carrying Value	$ 108	[1]	281	108	[1]	$ 406	[2]	$ 59	[1]
NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			(23)	46
Acquisition of businesses, net of cash acquired			0	0
Payments to Acquire Property, Plant, and Equipment			0	0
Increase (Decrease) in Restricted Cash			0	0
Increase (Decrease) in Notes Receivable			0	0
Proceeds from Renewable Energy Grants				0
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			0	0
Payments for (Proceeds from) Other Investing Activities				0
Net Cash Provided by (Used in) Investing Activities			(517)	0
Proceeds from Contributions from Parent				0
Payments of Capital Distribution				0
Proceeds from Payments to Intercompany Loans			(107)	49
Payments of Dividends			(61)	(44)
Proceeds from Issuance of Long-term Debt			0	0
Proceeds from (Repayments of) Debt			0	0
Proceeds from Related Party Debt			0	0
Payments of Financing Costs				0
Net Cash Provided by (Used in) Financing Activities			432	5
Cash and Cash Equivalents, Period Increase (Decrease)			(108)	51
Cash and Cash Equivalents, at Carrying Value	54		220	54		328		3
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			10
Acquisition of businesses, net of cash acquired			0
Payments to Acquire Property, Plant, and Equipment			0
Increase (Decrease) in Restricted Cash			0
Increase (Decrease) in Notes Receivable			0
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			(4)
Net Cash Provided by (Used in) Investing Activities			(4)
Proceeds from Payments to Intercompany Loans			(6)
Payments of Dividends			0
Proceeds from Issuance of Long-term Debt			0
Proceeds from (Repayments of) Debt			0
Proceeds from Related Party Debt			0
Net Cash Provided by (Used in) Financing Activities			(6)
Cash and Cash Equivalents, Period Increase (Decrease)			0
Cash and Cash Equivalents, at Carrying Value			0			0
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			69	(33)
Acquisition of businesses, net of cash acquired			0	21
Payments to Acquire Property, Plant, and Equipment			(8)	(29)
Increase (Decrease) in Restricted Cash			(7)	(49)
Increase (Decrease) in Notes Receivable			3	3
Proceeds from Renewable Energy Grants				137
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			0	0
Payments for (Proceeds from) Other Investing Activities				11
Net Cash Provided by (Used in) Investing Activities			2	192
Proceeds from Contributions from Parent				2
Payments of Capital Distribution				(25)
Proceeds from Payments to Intercompany Loans			0	0
Payments of Dividends			0	0
Proceeds from Issuance of Long-term Debt			5	41
Proceeds from (Repayments of) Debt			(580)	(154)
Proceeds from Related Party Debt			0	0
Payments of Financing Costs				(5)
Net Cash Provided by (Used in) Financing Activities			(88)	(141)
Cash and Cash Equivalents, Period Increase (Decrease)			(17)	18
Cash and Cash Equivalents, at Carrying Value	54		61	54		78		36
NRG Yield Operating LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Net Cash Provided by (Used in) Operating Activities			32	62
Acquisition of businesses, net of cash acquired			(37)	(357)
Payments to Acquire Property, Plant, and Equipment			0	0
Increase (Decrease) in Restricted Cash			0	0
Increase (Decrease) in Notes Receivable			0	2
Proceeds from Renewable Energy Grants				0
(Investments in) Proceeds From Sales of Unconsolidated Affiliates			(309)	(15)
Payments for (Proceeds from) Other Investing Activities				0
Net Cash Provided by (Used in) Investing Activities			(318)	(370)
Proceeds from Contributions from Parent				0
Payments of Capital Distribution				0
Proceeds from Payments to Intercompany Loans			113	(49)
Payments of Dividends			0	0
Proceeds from Issuance of Long-term Debt			282	0
Proceeds from (Repayments of) Debt			(18)	0
Proceeds from Related Party Debt			281	337
Payments of Financing Costs				0
Net Cash Provided by (Used in) Financing Activities			286	288
Cash and Cash Equivalents, Period Increase (Decrease)			0	(20)
Cash and Cash Equivalents, at Carrying Value	0		0	0		0		$ 20
Consolidation, Eliminations [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Cash and Cash Equivalents, at Carrying Value			0			$ 0
Drop-down Acquisition [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired	$ (357)		(489)	$ (336)
Drop-down Acquisition [Member] | NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			0
Drop-down Acquisition [Member] | Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			0
Drop-down Acquisition [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			0
Drop-down Acquisition [Member] | NRG Yield Operating LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Acquisition of businesses, net of cash acquired			$ (489)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.