Clearway Energy (CWEN.A) 10-Q 6 Nov 18 2018 Q3 Quarterly report Financial data

Document and Entity Information

Document and Entity Information - shares	9 Months Ended
	Sep. 30, 2018	Oct. 31, 2018
Class of Stock [Line Items]
Entity Registrant Name	Clearway Energy LLC
Entity Central Index Key	1,637,757
Document Type	10-Q
Document Period End Date	Sep. 30, 2018
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Non-accelerated Filer
Document Fiscal Year Focus	2,018
Document Fiscal Period Focus	Q3
Entity Emerging Growth Company	false
Entity Small Business	false
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		73,087,756
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				9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018		Sep. 30, 2017
Operating Revenues
Total operating revenues		$ 292		$ 269	[1]	$ 824		$ 778	[1]
Operating Costs and Expenses
Cost of operations		84		79	[1]	247		241	[1]
Depreciation and amortization		84		90	[1]	247		246	[1]
Asset Impairment Charges		0		12		0		12
General and administrative		6		4	[1]	17		14	[1]
Acquisition-related transaction and integration costs		17		0	[1]	19		2	[1]
Costs Incurred, Development Costs		1		0		1		0
Total operating costs and expenses		192		185	[1]	531		515	[1]
Operating Income		100		84	[1]	293		263	[1]
Costs and Expenses [Abstract]
Equity in earnings of unconsolidated affiliates		32		28	[1]	65		63	[1]
Other income, net		2		1	[1]	4		3	[1]
Gain (Loss) on Extinguishment of Debt		0		0	[1]	0		(2)	[1]
Interest expense		(70)		(71)	[1]	(190)		(229)	[1]
Total other income (expense), net		(36)		(42)	[1]	(121)		(165)	[1]
Net Income		64		42	[1]	172		98	[1]
Less: Loss attributable to noncontrolling interests		(2)		(23)	[1]	(95)		(56)	[1]
Net Income Attributable to Clearway Energy LLC		66		65	[1]	267		154	[1]
Consolidation, Eliminations [Member]
Operating Revenues
Total operating revenues		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Operating Costs and Expenses
Cost of operations		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Depreciation and amortization		0	[2]	0	[3]	0	[2]	0	[3]
Asset Impairment Charges				0				0
General and administrative		0	[2]	0	[3]	0	[2]	0	[3]
Acquisition-related transaction and integration costs		0	[2]			0	[2]	0	[3]
Costs Incurred, Development Costs	[2]	0				0
Total operating costs and expenses		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Operating Income		0	[2]	0	[3]	0	[2]	0	[3]
Costs and Expenses [Abstract]
Equity in earnings of unconsolidated affiliates		0	[2]	0	[3]	0	[2]	0	[3]
Other income, net		0	[2]	0	[3]	0	[2]	0	[3]
Gain (Loss) on Extinguishment of Debt	[3]							0
Interest expense		0	[2]	0	[3]	0	[2]	0	[3]
Total other income (expense), net		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3]
Net Income		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3],[4]
Less: Loss attributable to noncontrolling interests		2	[2]	1	[3]	66	[2]	3	[3]
Net Income Attributable to Clearway Energy LLC		$ (162)	[2]	$ (111)	[3]	$ (587)	[2]	$ (303)	[3]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.
[4]	(b) All significant intercompany transactions have been eliminated in consolidation.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	[1]	Sep. 30, 2018	Sep. 30, 2017	[1]
Net Income	$ 64	$ 42		$ 172	$ 98
Other Comprehensive Loss, net of tax
Unrealized gain on derivatives	7	7		34	7
Other comprehensive gain	7	7		34	7
Comprehensive Income	71	49		206	105
Less: Comprehensive loss attributable to noncontrolling interests	(2)	(23)		(95)	(56)
Comprehensive Income Attributable to Clearway Energy LLC	$ 73	$ 72		$ 301	$ 161
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($)	Sep. 30, 2018	Dec. 31, 2017
Current Assets
Cash and cash equivalents	$ 231,000,000	$ 146,000,000	[1]
Restricted cash	157,000,000	168,000,000	[1]
Accounts receivable — trade	141,000,000	95,000,000	[1]
Accounts receivable — affiliate	0	1,000,000	[1]
Inventory	39,000,000	39,000,000	[1]
Notes receivable	3,000,000	13,000,000	[1]
Prepayments and other current assets	31,000,000	19,000,000	[1]
Total current assets	602,000,000	481,000,000	[1]
Property, plant and equipment
Net property, plant and equipment	5,306,000,000	5,410,000,000	[1]
Other Assets
Equity investments in affiliates	1,182,000,000	1,178,000,000	[1]
Intangible assets, net	1,177,000,000	1,228,000,000	[1]
Derivative instruments	32,000,000	1,000,000	[1]
Other non-current assets	92,000,000	62,000,000	[1]
Other Assets	2,483,000,000	2,469,000,000	[1]
Total Assets	8,391,000,000	8,360,000,000	[1]
Current Liabilities
Current portion of long-term debt — external	309,000,000	339,000,000	[1]
Affiliate Current Debt	559,000,000	0	[1]
Accounts payable — trade	90,000,000	46,000,000	[1]
Accounts payable — affiliate	22,000,000	49,000,000	[1]
Derivative instruments	5,000,000	18,000,000	[1]
Accrued expenses and other current liabilities	95,000,000	87,000,000	[1]
Total current liabilities	1,080,000,000	539,000,000	[1]
Other Liabilities
Long-term debt — external	4,888,000,000	5,049,000,000	[1]
Long-term debt — affiliate	44,000,000	618,000,000	[1]
Derivative instruments	9,000,000	31,000,000	[1]
Other non-current liabilities	97,000,000	94,000,000	[1]
Total non-current liabilities	5,038,000,000	5,792,000,000	[1]
Total Liabilities	6,118,000,000	6,331,000,000	[1]
Commitments and Contingencies	0	0
Members' Equity
Contributed capital	1,937,000,000	1,919,000,000	[1]
Retained earnings	177,000,000	16,000,000	[1]
Accumulated other comprehensive loss	(34,000,000)	(68,000,000)	[1]
Noncontrolling interest	193,000,000	162,000,000	[1]
Total Members' Equity	2,273,000,000	2,029,000,000	[1]
Total Liabilities and Members’ Equity	$ 8,391,000,000	$ 8,360,000,000	[1]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Consolidated Statements Of Cas

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows from Operating Activities
Net Income	$ 172	$ 98	[1]
Adjustments to reconcile net (loss) income to net cash provided by operating activities:
Equity in earnings of unconsolidated affiliates	65	63	[1]
Distributions from unconsolidated affiliates	58	52	[1]
Depreciation and amortization	247	246	[1]
Amortization of financing costs	10	7	[1]
Amortization of intangibles and out-of-market contracts	52	52	[1]
Gain (Loss) on Extinguishment of Debt	0	(2)	[1]
Asset Impairment Charges	0	12
Derivative interest income	(39)	(5)	[1]
(Gain) loss on disposal of asset components	2	(8)	[1]
Changes in prepaid and accrued liabilities for tolling agreements	(8)	(5)	[1]
Changes in other working capital	(44)	(40)	[1]
Net Cash Provided by Operating Activities	397	374	[1]
Payments to Acquire Businesses, Net of Cash Acquired	11	0	[1]
Cash Flows from Investing Activities
Payments for the Drop Down Assets	126	176	[1]
Capital expenditures	(62)	(102)	[1]
Cash receipts from notes receivable	10	11	[1]
Return of investment from unconsolidated affiliates	22	32	[1]
Investments in unconsolidated affiliates	(16)	(48)	[1]
Other	(8)	0	[1]
Net Cash Used in Investing Activities	(175)	(283)	[1]
Cash Flows from Financing Activities
Net contributions from noncontrolling interests	108	13	[1]
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets	0	(26)	[1]
Net proceeds from the issuance of Class C units	151	33	[1]
Payments of distributions, net of contributions	(189)	(149)	[1]
Payments of debt issuance costs	(5)	(12)	[1]
Proceeds from the revolving credit facility	35	0	[1]
Repayments of Lines of Credit	(90)	0	[1]
Proceeds from the issuance of long-term debt — external	227	130	[1]
Payments for long-term debt — external	(369)	(255)	[1]
Repayments of Related Party Debt	(16)	0
Net Cash Used in Financing Activities	(148)	(266)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash	74	(175)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period	314	497	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period	$ 388	$ 322	[1]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Nature of Business

Nature of Business	9 Months Ended
	Sep. 30, 2018
Nature of Business Disclosure [Abstract]
Business Description and Basis of Presentation [Text Block]	Nature of Business Clearway Energy LLC (formerly NRG Yield LLC), together with its consolidated subsidiaries, or the Company, was formed by 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. On August 31, 2018, NRG Energy, or NRG, transferred its full ownership interest in Clearway Energy, Inc. (formerly NRG Yield, Inc.) to Clearway Energy Group LLC, or CEG, the holder of NRG's renewable energy development and operations platform, and subsequently sold 100% of its interest in CEG to Global Infrastructure Partners III, or GIP, referred to hereinafter as the NRG Transaction. As a result of the NRG Transaction, GIP indirectly acquired a 45.2% economic interest in Clearway Energy LLC and a 55% voting interest in the Company. GIP is an independent fund manager that invests in infrastructure assets in energy and transport sectors. The Company is sponsored by GIP through GIP's portfolio company, Clearway Energy Group. The Company’s environmentally-sound asset portfolio includes over 5,272 MW of wind, solar and natural gas-fired power generation facilities, as well as district energy systems. Nearly all of these assets sell substantially all of their output pursuant to long-term offtake agreements with creditworthy counterparties. The weighted average remaining contract duration of these offtake agreements was approximately 15 years as of September 30, 2018 based on CAFD. The Company also owns thermal infrastructure assets with an aggregate steam and chilled water capacity of 1,392 net MWt and electric generation capacity of 133 net MW. These thermal infrastructure assets provide steam, hot and/or chilled water, and, in some instances, electricity to commercial businesses, universities, hospitals and governmental units in multiple locations, principally through long-term contracts or pursuant to rates regulated by state utility commissions. The Company consolidates the results of Clearway Energy LLC through its controlling interest, with CEG's interest shown as noncontrolling interest in the financial statements. The holders of Clearway Energy, Inc.'s outstanding shares of Class A and Class C common stock are entitled to dividends as declared. CEG receives its distributions from Clearway Energy LLC through its ownership of Clearway Energy LLC Class B and Class D units. On September 27, 2018, Clearway Energy, Inc. issued and sold 3,916,449 shares of Class C common stock for net proceeds, after underwriting discounts and expenses, of $75 million . Clearway Energy, Inc. utilized the proceeds of the offering to acquire 3,916,449 Class C units from Clearway Energy LLC and, as a result, Clearway Energy, Inc. currently owns 55.7% of the economic interests of Clearway Energy LLC, with CEG retaining 44.3% of the economic interests of Clearway Energy LLC. . The following table represents the structure of the Company as of September 30, 2018 : As of September 30, 2018 , the Company's operating assets are comprised of the following projects: Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration Conventional El Segundo 100 % 550 Southern California Edison 2023 GenConn Devon 50 % 95 Connecticut Light & Power 2040 GenConn Middletown 50 % 95 Connecticut Light & Power 2041 Marsh Landing 100 % 720 Pacific Gas and Electric 2023 Walnut Creek 100 % 485 Southern California Edison 2023 1,945 Utility Scale Solar Agua Caliente 16 % 46 Pacific Gas and Electric 2039 Alpine 100 % 66 Pacific Gas and Electric 2033 Avenal 50 % 23 Pacific Gas and Electric 2031 Avra Valley 100 % 26 Tucson Electric Power 2032 Blythe 100 % 21 Southern California Edison 2029 Borrego 100 % 26 San Diego Gas and Electric 2038 Buckthorn Solar 100 % 154 City of Georgetown, TX 2043 CVSR 100 % 250 Pacific Gas and Electric 2038 Desert Sunlight 250 25 % 63 Southern California Edison 2034 Desert Sunlight 300 25 % 75 Pacific Gas and Electric 2039 Kansas South 100 % 20 Pacific Gas and Electric 2033 Roadrunner 100 % 20 El Paso Electric 2031 Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration TA High Desert 100 % 20 Southern California Edison 2033 Utah Solar Portfolio (b) (e) 50 % 265 PacifiCorp 2036 1,075 Distributed Solar Apple I LLC Projects 100 % 9 Various 2032 AZ DG Solar Projects 100 % 5 Various 2025 - 2033 SPP Projects 100 % 25 Various 2026 - 2037 Other DG Projects 100 % 13 Various 2023 - 2039 52 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 Alta XI (b) 100 % 90 Southern California Edison 2038 Buffalo Bear 100 % 19 Western Farmers Electric Co-operative 2033 Crosswinds (b) (f) 99 % 21 Corn Belt Power Cooperative 2027 Elbow Creek (b) (f) 100 % 122 NRG Power Marketing LLC 2022 Elkhorn Ridge (b) (f) 66.7 % 54 Nebraska Public Power District 2029 Forward (b) (f) 100 % 29 Constellation NewEnergy, Inc. 2022 Goat Wind (b) (f) 100 % 150 Dow Pipeline Company 2025 Hardin (b) (f) 99 % 15 Interstate Power and Light Company 2027 Laredo Ridge 100 % 80 Nebraska Public Power District 2031 Lookout (b) (f) 100 % 38 Southern Maryland Electric Cooperative 2030 Odin (b) (f) 99.9 % 20 Missouri River Energy Services 2028 Pinnacle 100 % 55 Maryland Department of General Services and University System of Maryland 2031 San Juan Mesa (b) (f) 75 % 90 Southwestern Public Service Company 2025 Sleeping Bear (b) (f) 100 % 95 Public Service Company of Oklahoma 2032 South Trent 100 % 101 AEP Energy Partners 2029 Spanish Fork (b) (f) 100 % 19 PacifiCorp 2028 Spring Canyon II (b) 90.1 % 29 Platte River Power Authority 2039 Spring Canyon III (b) 90.1 % 25 Platte River Power Authority 2039 Taloga 100 % 130 Oklahoma Gas & Electric 2031 Wildorado (b) (f) 100 % 161 Southwestern Public Service Company 2027 2,200 Thermal Energy Center Dover LLC 100 % 103 NRG Power Marketing LLC 2018 Thermal generation 100 % 30 Various Various 133 Total net generation capacity (c) 5,405 Thermal equivalent MWt (d) 100 % 1,392 Various Various (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 September 30, 2018 . (b) Projects are part of tax equity arrangements . (c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs. (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. (e) Represents interests in Four Brothers Solar, LLC, Granite Mountain Holdings, LLC, and Iron Springs Holdings, LLC, all acquired as part of the March 2017 Drop Down Assets (ownership percentage is based upon cash to be distributed). (f) Projects are part of Wind TE Holdco portfolio. In addition to the facilities owned or leased in the table above, the Company has entered into partnerships to own or purchase solar power generation projects, as well as other ancillary related assets from a related party via intermediate funds. The Company does not consolidate these partnerships and accounts for them as equity method investments. The Company's net interest in these projects is 268 MW based on cash to be distributed pursuant to the partnership agreements as of September 30, 2018 . For further discussions, see Note 4 , Investments Accounted for by the Equity Method and Variable Interest Entities of this Form 10-Q and Note 5 , Investments Accounted for by the Equity Method and Variable Interest Entities to the consolidated financial statements included in the Company's 2017 Form 10-K. 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. Certain district energy systems are subject to rate regulation by state public utility commissions (although they may negotiate certain rates) while the other district energy systems have rates determined by negotiated bilateral contracts. Recast of the Historical Financial Statements Prior to the NRG Transaction on August 31, 2018, the Company completed several acquisitions of Drop Down Assets from NRG, which were accounted for as transfer of entities under common control. The accounting guidance for transfers of entities under common control requires retrospective combination of the entities for all periods presented as if the combinations had been in effect from the beginning of the financial statement period or from the date the entities were under common control (if later than the beginning of the financial statement period). The transfers of entities under common control that took place in 2017 and 2018, and affected the historical results in reporting periods in this Form 10-Q as further described in Note 3, Business Acquisitions are: (i) the acquisition of 100% of NRG's interest in Buckthorn Renewables, LLC, or the Buckthorn Solar Drop Down Asset on March 30, 2018, and (ii) in 2017, the acquisition of the November 2017 November Drop Down Assets and August 2017 Drop Down Assets from NRG.

Summary of Significant Accounti

Summary of Significant Accounting Policies	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Use of Estimates The preparation of consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions. These estimates and assumptions impact the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could be different from these estimates. Accumulated Depreciation, Accumulated Amortization The following table presents the accumulated depreciation included in the property, plant and equipment, net, and accumulated amortization included in intangible assets, net, respectively, as of September 30, 2018 and December 31, 2017 : September 30, 2018 December 31, 2017 (In millions) Property, Plant and Equipment Accumulated Depreciation $ 1,507 $ 1,285 Intangible Assets Accumulated Amortization 289 237 Noncontrolling Interests Noncontrolling interests represent the equity associated with CEG's interest in Repowering Partnership LLC, as described in Note 4, Investments Accounted for by the Equity Method and Variable Interest Entities , and 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 tax credits. The following table reflects the changes in the Company's noncontrolling interest balance for the period from January 1, 2018 through September 30, 2018: (In millions) Balance as of December 31, 2017 $ 162 Capital contributions from tax equity investors, net of distributions (a) 108 Comprehensive loss (95 ) Contributions from CEG (b) 18 Balance as of September 30, 2018 $ 193 (a) Activity primarily relates to net capital contributions from the TE investor into Buckthorn Holdings LLC in the amount of $99 million , as further described in Note 4, Investments Accounted for by the Equity Method and Variable Interest Entities . (b) Contributions from CEG are primarily comprised of non-cash contribution of $17 million made by CEG in connection with the formation of Repowering Partnership LLC, as further described in Note 4, Investments Accounted for by the Equity Method and Variable Interest Entities . Distributions The following table lists the distributions paid on Clearway Energy LLC's Class A, B, C and D units during the nine months ended September 30, 2018 : Third Quarter 2018 Second Quarter 2018 First Quarter 2018 Distributions per Class A, B, C and D unit $ 0.320 $ 0.309 $ 0.298 On October 31, 2018 , Clearway Energy LLC declared a distribution on its Class A, Class B, Class C and Class D units of $0.331 per unit payable on December 17, 2018 to unit holders of record as of December 3, 2018 . Changes in Capital Structure At-the-Market Equity Offering Program, or the ATM Program Clearway Energy, Inc. is party to an equity distribution agreement with Barclays Capital Inc., Credit Suisse Securities (USA) LLC, J.P. Morgan Securities LLC and RBC Capital Markets, LLC, as sales agents. Pursuant to the terms of the equity distribution agreement, Clearway Energy, Inc. may offer and sell shares of its Class C common stock par value $0.01 per share, from time to time through the sales agents up to an aggregate sales price of $150 million through an at-the-market equity offering program, or the ATM Program. Clearway Energy, Inc. may also sell shares of its Class C common stock to any of the sales agents, as principals for its own account, at a price agreed upon at the time of sale. Clearway Energy, Inc. sold a total of 4,392,583 of Class C common stock for gross proceeds of $77 million during the period ended September 30, 2018 . Clearway Energy, Inc. used the net proceeds to acquire 4,392,583 Class C units from the Company. As of September 30, 2018 , approximately $38 million remains available for issuance under the ATM Program. Revenue Recognition Revenue from Contracts with Customers On January 1, 2018, the Company adopted the guidance in ASC 606, Revenue from Contracts with Customers, or Topic 606, using the modified retrospective method applied to contracts which were not completed as of the adoption date, with no adjustment required to the financial statements upon adoption. Following the adoption of the new standard, the Company’s revenue recognition of its contracts with customers remains materially consistent with its historical practice. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. The Company's policies with respect to its various revenue streams are detailed below. In general, the Company applies the invoicing practical expedient to recognize revenue for the revenue streams detailed below, except in circumstances where the invoiced amount does not represent the value transferred to the customer. Thermal Revenues Steam and chilled water revenue is recognized as the Company transfers the product to the customer, based on customer usage as determined by meter readings taken at month-end. Some locations read customer meters throughout the month, and recognize estimated revenue for the period between meter read date and month-end. For thermal contracts, the Company’s performance obligation to deliver steam and chilled water is satisfied over time and revenue is recognized based on the invoiced amount. The Thermal Business subsidiaries collect and remit state and local taxes associated with sales to their customers, as required by governmental authorities. These taxes are presented on a net basis in the income statement. As contracts for steam and chilled water are long-term contracts, the Company has performance obligations under these contracts that have not yet been satisfied. These performance obligations have transaction prices that are both fixed and variable, and that vary based on the contract duration, customer type, inception date and other contract-specific factors. For the fixed price contracts, the Company cannot accurately estimate the amount of its unsatisfied performance obligations as it will vary based on customer usage, which will depend on factors such as weather and customer activity. Power Purchase Agreements, or PPAs The majority of the Company’s revenues are obtained through PPAs or other contractual agreements. Energy, capacity and where applicable, renewable attributes, from the majority of the Company’s renewable energy assets and certain conventional energy plants is sold through long-term PPAs and tolling agreements to a single counterparty, which is often a utility or commercial customer. The majority of these PPAs are accounted for as leases. ASC 840 requires the minimum lease payments received to be amortized over the term of the lease and contingent rentals are recorded when the achievement of the contingency becomes probable. Judgment is required by management in determining the economic life of each generating facility, in evaluating whether certain lease provisions constitute minimum payments or represent contingent rent and other factors in determining whether a contract contains a lease and whether the lease is an operating lease or capital lease. Renewable Energy Credits, or RECs As stated above, renewable energy credits, or RECs, are usually sold through long-term PPAs. Revenue from the sale of self-generated RECs is recognized when the related energy is generated and simultaneously delivered even in cases where there is a certification lag as it has been deemed to be perfunctory. In a bundled contract to sell energy, capacity and/or self-generated RECs, all performance obligations are deemed to be delivered at the same time and hence, timing of recognition of revenue for all performance obligations is the same and occurs over time. In such cases, it is often unnecessary to allocate transaction price to multiple performance obligations. Sale of Emission Allowances The Company records its bank of emission allowances as part of intangible assets. From time to time, management may authorize the transfer of emission allowances in excess of usage from the Company's emission bank to intangible assets held-for-sale for trading purposes. The Company records the sale of emission allowances on a net basis within operating revenue in the Company's consolidated statements of operations. Disaggregated Revenues The following tables represent the Company’s disaggregation of revenue from contracts with customers for the three and nine months ended September 30, 2018 , along with the reportable segment for each category: Three months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Total Energy revenue (a) $ 2 $ 167 $ 50 $ 219 Capacity revenue (a) 86 — 4 90 Contract amortization (1 ) (15 ) (1 ) (17 ) Total operating revenue 87 152 53 292 Less: Lease revenue (88 ) (158 ) — (246 ) Less: Contract amortization 1 15 1 17 Total revenue from contracts with customers $ — $ 9 $ 54 $ 63 (a) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Total Energy Revenue $ 2 $ 158 $ 160 Capacity Revenue 86 — 86 88 158 246 Nine months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Total Energy revenue (b) $ 5 $ 473 $ 139 $ 617 Capacity revenue (b) 250 — 9 259 Contract amortization (4 ) (46 ) (2 ) (52 ) Total operating revenue 251 427 146 824 Less: Lease revenue (255 ) (438 ) (1 ) (694 ) Less: Contract amortization 4 46 2 52 Total revenue from contracts with customers $ — $ 35 $ 147 $ 182 (b) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Thermal Total Energy Revenue $ 5 $ 438 $ 1 $ 444 Capacity Revenue 250 — — 250 255 438 1 694 Contract Amortization Assets and liabilities recognized from power sales agreements assumed through acquisitions related to the sale of electric capacity and energy in future periods for which the fair value has been determined to be significantly less (more) than market are amortized to revenue over the term of each underlying contract based on actual generation and/or contracted volumes or on a straight-line basis, where applicable. Contract Balances The following table reflects the contract assets and liabilities included on the Company’s balance sheet as of September 30, 2018 : (In millions) September 30, 2018 Accounts receivable, net - Contracts with customers $ 35 Accounts receivable, net - Leases 106 Total accounts receivable, net $ 141 Reclassifications Certain prior-year amounts have been reclassified for comparative purposes. Recent Accounting Developments - Not Yet Adopted ASU 2016-02 — In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), or Topic 842, with the objective to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and to improve financial reporting by expanding the related disclosures. The guidance in Topic 842 provides that a lessee that may have previously accounted for a lease as an operating lease under current GAAP should recognize the assets and liabilities that arise from a lease on the balance sheet. In addition, Topic 842 expands the required quantitative and qualitative disclosures with regards to lease arrangements. The Company will adopt the standard effective January 1, 2019 and expects to elect certain of the practical expedients permitted, including the expedient that permits the Company to retain its existing lease assessment and classification. The Company is currently working through an adoption plan and evaluating the anticipated impact on the Company's results of operations, cash flows and financial position. While the Company is currently evaluating the impact the new guidance will have on its financial position and results of operations, the Company expects to recognize lease liabilities and right of use assets. The extent of the increase to assets and liabilities associated with these amounts remains to be determined pending the Company’s review of its existing lease contracts and service contracts which may contain embedded leases. While this review is still in process, the Company believes the adoption of Topic 842 may be material to its financial statements. The Company is continuing to monitor potential changes to Topic 842 that have been proposed by the FASB and will assess any necessary changes to the implementation as the guidance is updated.

Business Acquisitions Business

Business Acquisitions Business Acquisitions (Notes)	9 Months Ended
	Sep. 30, 2018
Business Acquisitions [Abstract]
Mergers, Acquisitions and Dispositions Disclosures [Text Block]	Business Acquisitions 2018 Acquisitions UPMC Thermal Project Asset Acquisition — On June 19, 2018, upon reaching substantial completion, the Company acquired from NRG the UPMC Thermal Project for cash consideration of $84 million , subject to working capital adjustments. The Company will pay an additional $5 million to NRG upon final completion of the project pursuant to the EPC agreement. The project adds 73 MWt of thermal equivalent capacity and 7.5 MW of emergency backup thermal capacity to the Company's portfolio. The transaction is reflected in the Company's Thermal segment. The acquisition was funded with the proceeds from the sale of the Series E Notes and Series F Notes, as further described in Note 7 , Long-term Debt . The assets transferred to the Company relate to interests under common control by NRG and were recorded at book value in accordance with ASC 805-50, Business Combinations - Related Issues . The difference between the purchase price and book value of the assets was recorded as a distribution to NRG and decreased the balance of contributed capital. The acquisition was determined to be an asset acquisition and not a business combination, therefore no recast of the historical financial information was deemed necessary. Central CA Fuel Cell 1, LLC — On April 18, 2018 , the Company acquired the Central CA Fuel Cell 1, LLC project in Tulare, California from FuelCell Energy Finance, Inc., for cash consideration of $11 million , subject to working capital adjustments. The project adds 2.8 MW of thermal capacity to the Company's portfolio, with a 20 -year PPA contract with the City of Tulare. The transaction is reflected in the Company's Thermal segment. Buckthorn Solar Drop Down Asset — On March 30, 2018 , the Company acquired 100% of NRG's interests in Buckthorn Renewables, LLC, which owned a 154 MW construction-stage utility-scale solar generation project located in Texas, or the Buckthorn Solar Drop Down Asset, for cash consideration of approximately $42 million , subject to working capital adjustments. The Company also assumed non-recourse debt of $ 183 million and non-controlling interest of $19 million (as of acquisition date) attributable to the Class A member, as further described below. The Company converted $132 million of non-recourse debt to a term loan and the remainder of the outstanding debt was paid down with the contribution from the Class A member in the amount of $80 million upon the project reaching substantial completion in May 2018. The purchase price for the Buckthorn Solar Drop Down Asset was funded with cash on hand and borrowings from the Company's revolving credit facility. The assets and liabilities transferred to the Company related 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 historical value of the entities' equity was recorded as a distribution to NRG and decreased the balance of contributed capital. Since the transaction constituted a transfer of net assets under common control, the guidance requires retrospective combination of the entities for all periods presented as if the combination had been in effect since the inception of common control. Buckthorn Solar Portfolio, LLC, a wholly owned subsidiary of Buckthorn Renewables, LLC, is the Class B member in a tax equity partnership, Buckthorn Holdings, LLC, the owner of the Buckthorn Solar Drop Down Asset. The Class A member is a tax equity investor, or TE investor, who receives 99% of allocations of taxable income and other items through the six month anniversary of the placed in service date, at which time the allocations change to 67% through the last calendar year before the flip point, and then back to 99% through the flip point (which occurs when the TE Investor obtains a specified return on its initial investment), at which time the allocations to the TE Investor change to 5% for all the periods thereafter. Before the flip point, the TE investor would receive a priority distribution of distributable cash, as defined, plus a percentage of remaining distributable cash after the priority distribution subject to a percentage cap. The project sells power under a 25-year PPA to the City of Georgetown, Texas, which commenced in July 2018. The following is a summary of net assets transferred in connection with the acquisition of the Buckthorn Solar Drop Down Asset as of March 31, 2018: (In millions) Assets: Current assets $ 20 Property, plant and equipment 212 Non-current assets 3 Total assets 235 Liabilities: Debt (Current and non-current) (a) 176 Other current and non-current liabilities 15 Total liabilities 191 Less: noncontrolling interest 19 Net assets acquired $ 25 (a) Net of $7 million of net debt issuance costs. 2017 Acquisitions November 2017 Drop Down Assets — On November 1, 2017, the Company acquired a 38 MW solar portfolio primarily comprised of assets from NRG's Solar Power Partners (SPP) funds and other projects developed by NRG , for cash consideration of $74 million , including working capital adjustments, plus assumed non-recourse debt of $26 million . The purchase price for the November 2017 Drop Down Assets was funded with cash on hand. 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 historical value of the entities' equity was recorded as an adjustment to contributed capital. Since the transaction constituted a transfer of net 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. The following tables present a summary of the Company's historical information combining the financial information for the Buckthorn Solar Drop Down Asset and November 2017 Drop Down Assets transferred in connection with the acquisition: Three months ended September 30, 2017 As Previously Reported (a) Buckthorn Solar Drop Down Asset November 2017 Drop Down Assets As Currently Reported (In millions) Total operating revenues $ 265 $ — $ 4 $ 269 Operating income (loss) 95 — (11 ) 84 Net income (loss) 52 1 (11 ) 42 Less: Loss attributable to noncontrolling interests (23 ) — — (23 ) Net income (loss) attributable to Clearway Energy LLC 75 1 (11 ) 65 Nine months ended September 30, 2017 As Previously Reported (a) Buckthorn Solar Drop Down Asset November 2017 Drop Down Assets As Currently Reported (In millions) Total operating revenues $ 767 $ — $ 11 $ 778 Operating income 271 — (8 ) 263 Net income (loss) 110 (2 ) (10 ) 98 Less: Loss attributable to noncontrolling interests (56 ) — — (56 ) Net income (loss) attributable to Clearway Energy LLC 166 (2 ) (10 ) 154 (a) As previously reported in the Company's Form 10-Q for the quarter ended September 30, 2017. August 2017 Drop Down Assets — On August 1, 2017, the Company acquired the remaining 25% interest in Wind TE Holdco, a portfolio of 12 wind projects, from NRG for total cash consideration of $44 million , including working capital adjustments. The purchase agreement also included potential additional payments to NRG dependent upon actual energy prices for merchant periods beginning in 2027, which were estimated and accrued as contingent consideration in the amount of $8 million . The Company originally acquired 75% of Wind TE Holdco on November 3, 2015, or November 2015 Drop Down Assets, which were consolidated with 25% of the net assets recorded as noncontrolling interest. The assets and liabilities transferred to the Company related to interests under common control by NRG and were recorded at historical cost in accordance with ASC 805-50, Business Combination - Related Issues. The difference between the cash paid of $44 million , net of the contingent consideration of $8 million , and the historical value of the remaining 25% of $87 million as of July 31, 2017, was recorded as an adjustment to NRG's contributed capital. Since the transaction constituted a transfer 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 from the beginning of the financial statement period or from the date the entities were under common control (if later than the beginning of the financial statement period). March 2017 Drop Down Assets — On March 27, 2017, the Company acquired the following interests from NRG: (i) Agua Caliente Borrower 2 LLC, which owns a 16% interest (approximately 31% of NRG's 51% interest) in the Agua Caliente solar farm, one of the ROFO Assets, representing ownership of approximately 46 net MW of capacity and (ii) NRG's interests in the Utah Solar Portfolio. Agua Caliente is located in Yuma County, AZ and sells power subject to a 25 -year PPA with Pacific Gas and Electric, with 22 years remaining on that contract. The seven utility-scale solar farms in the Utah Solar Portfolio are owned by the following entities: Four Brothers Capital, LLC, Iron Springs Capital, LLC, and Granite Mountain Capital, LLC. These utility-scale solar farms achieved commercial operations in 2016, sell power subject to 20 -year PPAs with PacifiCorp, a subsidiary of Berkshire Hathaway and are part of a tax equity structure with Dominion Solar Projects III, Inc., or Dominion, through which the Company is entitled to receive 50% of cash to be distributed, as further described below. The Company paid cash consideration of $128 million , which includes $3 million of final net working capital adjustment received by the Company from NRG. The acquisition of the March 2017 Drop Down Assets was funded with cash on hand. The Company recorded the acquired interests as equity method investments. The Company also assumed non-recourse debt of $41 million and $287 million on Agua Caliente Borrower 2 LLC and the Utah Solar Portfolio, respectively, as well as its pro-rata share of non-recourse project-level debt of Agua Caliente Solar LLC, as further described in Note 4 , Investments Accounted for by the Equity Method and Variable Interest Entities . 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 Combination - Related Issues. The difference between the cash paid and the historical value of the entities' equity of $8 million was recorded as an adjustment to contributed capital. Since the transaction constituted a transfer 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 from the beginning of the financial statement period or from the date the entities were under common control (if later than the beginning of the financial statement period).

Variable Interest Entities

Variable Interest Entities	9 Months Ended
	Sep. 30, 2018
Equity Method Investments and Joint Ventures [Abstract]
Investments Accounted for by the Equity Method and Variable Interest Entities	Investments Accounted for by the Equity Method and Variable Interest Entities Entities that are Consolidated The Company has a controlling financial interest in certain entities which have been identified as VIEs under ASC 810, Consolidations, or ASC 810. These arrangements are primarily related to tax equity arrangements entered into with third parties in order to monetize certain tax credits associated with wind facilities, as further described in Note 5 , Investments Accounted for by the Equity Method and Variable Interest Entities , to the consolidated financial statements included in the Company's 2017 Form 10 -K. Buckthorn Renewables, LLC — As described in Note 3 , Business Acquisitions , on March 30, 2018, the Company acquired 100% of NRG’s interest in a 154 MW construction-stage utility-scale solar generation project, Buckthorn Renewables, LLC, which owns 100% interest in Buckthorn Solar Portfolio, LLC, which in turn owns 100% of the Class B membership interests in Buckthorn Holdings, LLC . Buckthorn Holdings, LLC is a tax equity fund, which is a variable interest entity that is consolidated by Buckthorn Solar Portfolio, LLC. The Company is the primary beneficiary, through its position as managing member, and indirectly consolidates Buckthorn Holdings, LLC through Buckthorn Solar Portfolio, LLC. The Class A member is a tax equity investor who made its initial contribution of $19 million on March 30, 2018, which is reflected as noncontrolling interest on the Company’s consolidated balance sheet. The project achieved substantial completion in May 2018, at which time the remaining tax equity contributions of $80 million were funded. The Company utilizes the HLBV method to determine the net income or loss allocated to the tax equity investor noncontrolling interest. The Company recorded $55 million of loss attributable to noncontrolling interest in Buckthorn Renewables, LLC during the period ended September 30, 2018 . Repowering Partnership LLC — On August 30, 2018, Wind TE Holdco, an indirect subsidiary of the Company, entered into a partnership with Clearway Renew LLC, an indirect subsidiary of CEG, in order to facilitate the repowering of the Elbow Creek and Wildorado facilities. Wind TE Holdco contributed its interests in the two facilities and Clearway Renew LLC contributed a turbine supply agreement, including title to certain components that qualify for production tax credits. Clearway Renew LLC paid a $17 million deposit and had a payable for an additional $17 million due to the service provider, which will be funded by an additional contribution from Clearway Renew LLC. Wind TE Holdco is the managing member of Repowering Partnership LLC and consolidates the entity, which is a VIE. Clearway Renew LLC is entitled to allocations of 21% of income, which is reflected in Wind TE Holdco’s noncontrolling interests. Summarized financial information for the Company's consolidated VIEs consisted of the following as of September 30, 2018 : (In millions) Wind TE Holdco Alta Wind TE Holdco Spring Canyon Buckthorn Renewables, LLC Other current and non-current assets $ 192 $ 32 $ 1 $ 21 Property, plant and equipment 354 417 92 225 Intangible assets 2 253 — — Total assets 548 702 93 246 Current and non-current liabilities 205 14 5 136 Total liabilities 205 14 5 136 Noncontrolling interest 32 67 50 44 Net assets less noncontrolling interests $ 311 $ 621 $ 38 $ 66 Entities that are not Consolidated The Company has interests in entities that are considered VIEs under ASC 810, but for which it is not considered the primary beneficiary. The Company accounts for its interests in these entities under the equity method of accounting, as further described in Note 5 , Investments Accounted for by the Equity Method and Variable Interest Entities , to the consolidated financial statements included in the Company's 2017 Form 10-K . The Company's maximum exposure to loss as of September 30, 2018 , is limited to its equity investment in the unconsolidated entities, as further summarized in the table below: (In millions) Maximum exposure to loss Four Brothers Solar, LLC $ 204 GenConn Energy LLC 98 DGPV Holdco 3 LLC 85 DGPV Holdco 1 LLC 78 Granite Mountain Holdings, LLC 74 DGPV Holdco 2 LLC 63 Iron Springs Holdings, LLC 52 RPV Holdco 1 LLC 42 DGPV Holdco 1 LLC — The Company invested $4 million of cash during the nine months ended September 30, 2018 into DGPV Holdco 1 LLC and recorded $1 million due to CEG in accounts payable — affiliate as of September 30, 2018 to be funded as the project milestones are completed. The Company owns approximately 52 MW of distributed solar capacity, based on cash to be distributed, with a weighted average remaining contract life of approximately 17 years as of September 30, 2018 . DGPV Holdco 3 LLC — The Company invested $12 million of cash during the nine months ended September 30, 2018 into DGPV Holdco 3 LLC and recorded $10 million due to CEG in accounts payable — affiliate as of September 30, 2018 to be funded in tranches as the project milestones are completed. The Company owns approximately 59 MW of distributed solar capacity, based on cash to be distributed, with a weighted average remaining contract life of approximately 21 years as of September 30, 2018 . Utah Solar Portfolio — As described in Note 3, Business Acquisitions , on March 27, 2017, as part of the March 2017 Drop Down Assets acquisition, the Company acquired from NRG 100% of the Class A equity interests in the Utah Solar Portfolio, comprised of Four Brothers Solar, LLC, Granite Mountain Holdings, LLC, and Iron Springs Holdings, LLC. The Class B interests of the Utah Solar Portfolio are owned by a tax equity investor, who receives 99% of allocations of taxable income and other items until the flip point, which occurs when the tax equity investor obtains a specified return on its initial investment, at which time the allocations to the tax equity investor change to 50% . The Company generally receives 50% of distributable cash throughout the term of the tax-equity arrangements. The three entities comprising the Utah Solar Portfolio are VIEs. As the Company is not the primary beneficiary, the Company uses the equity method of accounting to account for its interests in the Utah Solar Portfolio. The Company utilizes the HLBV method to determine its share of the income or losses in the investees.

Fair Value of Financial Instrum

Fair Value of Financial Instruments	9 Months Ended
	Sep. 30, 2018
Fair Value Disclosures [Abstract]
Fair Value of Financial Instruments	Fair Value of Financial Instruments 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. For cash and cash equivalents, restricted cash, accounts receivable, accounts payable, accounts payable — affiliates, 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 September 30, 2018 As of December 31, 2017 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Assets: Notes receivable $ 3 $ 3 $ 13 $ 13 Liabilities: Long-term debt — affiliate, including current portion 603 603 618 618 Long-term debt — external, including current portion (a) $ 5,253 $ 5,218 $ 5,450 $ 5,466 (a) Excludes deferred financing costs, which are recorded as a reduction to long-term debt on the Company's consolidated balance sheets. The fair value of the Company's publicly-traded long-term debt is based on quoted market prices and is classified as Level 2 within the fair value hierarchy. The fair value of non-publicly traded long-term debt and certain notes receivable of the Company are based on expected future cash flows discounted at market interest rates, or current interest rates for similar instruments with equivalent credit quality and are classified as Level 3 within the fair value hierarchy. The following table presents the level within the fair value hierarchy for long-term debt, including current portion as of September 30, 2018 and December 31, 2017 : As of September 30, 2018 As of December 31, 2017 Level 2 Level 3 Level 2 Level 3 (In millions) Long-term debt, including current portion $ 834 $ 4,987 $ 870 $ 5,214 Recurring Fair Value Measurements The Company records its derivative assets and liabilities at fair 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 September 30, 2018 As of December 31, 2017 Fair Value (a) Fair Value (a) (In millions) Level 2 Level 2 Derivative assets: Commodity contracts $ — $ 1 Interest rate contracts 35 1 Total assets 35 2 Derivative liabilities: Commodity contracts 1 1 Interest rate contracts 13 48 Total liabilities $ 14 $ 49 (a) There were no derivative assets or liabilities classified as Level 1 or Level 3 as of September 30, 2018 and December 31, 2017 . Derivative Fair Value Measurements 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 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, for interest rate swaps, calculated based on credit default swaps using the bilateral method. For commodities, to the extent that the net exposure under a specific master agreement is an asset, the Company uses the counterparty’s default swap rate. If the net exposure under a specific master agreement is a liability, the Company uses a proxy of its own default swap rate. For interest rate swaps and commodities, 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 September 30, 2018 , the credit reserve was $1 million in interest expense . 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 In addition to the credit risk discussion in Note 2 , Summary of Significant Accounting Policies , to the consolidated financial statements included in the Company's 2017 Form 10-K, the following is a discussion of the concentration of credit risk for the Company's financial instruments. 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) 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 September 30, 2018 , credit risk exposure to these counterparties attributable to the Company's ownership interests was approximately $2.5 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 (Notes)	9 Months Ended
	Sep. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Accounting for Derivative Instruments and Hedging Activities	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 consolidated financial statements included in the Company's 2017 Form 10-K. Energy-Related Commodities As of September 30, 2018 , the Company had energy-related derivative instruments extending through 2020. At September 30, 2018 , these contracts were not designated as cash flow or fair value hedges. Interest Rate Swaps As of September 30, 2018 , the Company had interest rate derivative instruments on non-recourse debt extending through 2041, a portion of which are designated as cash flow hedges. Volumetric Underlying Derivative Transactions The following table summarizes the net notional volume buy of the Company's open derivative transactions broken out by type: Total Volume September 30, 2018 December 31, 2017 Commodity Units (In millions) Natural Gas MMBtu 2 2 Interest Dollars $ 1,909 $ 2,050 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 (a) Derivative Liabilities September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (In millions) Derivatives Designated as Cash Flow Hedges: Interest rate contracts current $ 2 $ — $ 1 $ 4 Interest rate contracts long-term 11 1 4 9 Total Derivatives Designated as Cash Flow Hedges 13 1 5 13 Derivatives Not Designated as Cash Flow Hedges : Interest rate contracts current 1 — 3 13 Interest rate contracts long-term 21 — 5 22 Commodity contracts current — 1 1 1 Total Derivatives Not Designated as Cash Flow Hedges 22 1 9 36 Total Derivatives $ 35 $ 2 $ 14 $ 49 (a) Derivative Assets balances classified as current are included within the prepayments and other current assets line item of the consolidated balance sheets as of September 30, 2018 and December 31, 2017 . 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 September 30, 2018 and December 31, 2017 , there was no outstanding collateral paid or received. The following tables summarize the offsetting of derivatives by the counterparty master agreement level as of September 30, 2018 and December 31, 2017 : As of September 30, 2018 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts (a) : (In millions) Derivative liabilities $ (1 ) $ — $ (1 ) Total commodity contracts (1 ) — (1 ) Interest rate contracts: Derivative assets 35 (2 ) 33 Derivative liabilities (13 ) 2 (11 ) Total interest rate contracts 22 — 22 Total derivative instruments $ 21 $ — $ 21 (a) There were no commodity contracts classified as derivative assets as of September 30, 2018 . As of December 31, 2017 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ 1 $ — $ 1 Derivative liabilities (1 ) — (1 ) Total commodity contracts — — — Interest rate contracts: Derivative assets 1 (1 ) — Derivative liabilities (48 ) 1 (47 ) Total interest rate contracts (47 ) — (47 ) Total derivative instruments $ (47 ) $ — $ (47 ) 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 September 30, Nine months ended September 30, 2018 2017 2018 2017 (In millions) Accumulated OCL beginning balance $ (42 ) $ (86 ) $ (69 ) $ (86 ) Reclassified from accumulated OCL to income due to realization of previously deferred amounts 5 5 13 13 Mark-to-market of cash flow hedge accounting contracts 2 2 21 (6 ) Accumulated OCL ending balance (35 ) (79 ) (35 ) (79 ) Accumulated OCL attributable to noncontrolling interests (1 ) (1 ) (1 ) (1 ) Accumulated OCL attributable to Clearway Energy LLC $ (34 ) $ (78 ) $ (34 ) $ (78 ) Losses expected to be realized from OCL during the next 12 months $ (9 ) $ (9 ) The Company's regression analysis for Marsh Landing, Walnut Creek and Avra Valley interest rate swaps, while positively correlated, no longer contain matching terms for cash flow hedge accounting. As a result, the Company voluntarily de-designated the Marsh Landing, Walnut Creek and Avra Valley cash flow hedges as of April 28, 2017, and will prospectively mark these derivatives to market through the income statement. 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 September 30, 2018 and 2017 , the impact to the consolidated statements of operations was a gain of $9 million and a gain of $7 million , respectively. For the nine months ended September 30, 2018 and 2017 , the impact to the consolidated statements of operations was a gain of $40 million and a loss of $2 million , respectively. A portion of the Company’s derivative commodity contracts relates 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. See Note 5 , Fair Value of Financial Instruments , for a discussion regarding concentration of credit risk.

Long-term Debt

Long-term Debt	9 Months Ended
	Sep. 30, 2018
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt This footnote should be read in conjunction with the complete description under Note 10 , Long-term Debt , to the consolidated financial statements included in the Company's 2017 Form 10-K. Long-term debt consisted of the following: September 30, 2018 December 31, 2017 September 30, 2018, interest rate % (a) Letters of Credit Outstanding at September 30, 2018 (In millions, except rates) Long-term debt - affiliate, due 2019 $ 322 $ 337 3.580 $ — Long-term debt - affiliate, due 2020 281 281 3.325 — 2024 Senior Notes 500 500 5.375 — 2026 Senior Notes 350 350 5.000 — Clearway Energy LLC and Clearway Energy Operating LLC Revolving Credit Facility, due 2023 (b) — 55 L+1.50 70 Project-level debt: Agua Caliente Borrower 2, due 2038 39 41 5.430 17 Alpine, due 2022 129 135 L+1.750 16 Alta Wind I - V lease financing arrangements, due 2034 and 2035 901 926 5.696 - 7.015 103 Buckthorn Solar, due 2025 132 169 L+1.750 26 CVSR, due 2037 720 746 2.339 - 3.775 — CVSR Holdco Notes, due 2037 188 194 4.680 13 El Segundo Energy Center, due 2023 352 400 L+1.75 - L+2.375 138 Energy Center Minneapolis Series C Notes, due 2025 — 83 5.950 — Energy Center Minneapolis Series D Notes, due 2031 125 125 3.550 — Energy Center Minneapolis Series E, F, G, H Notes 203 — various — Laredo Ridge, due 2028 91 95 L+1.875 10 Marsh Landing, due 2023 280 318 L+2.125 38 Tapestry, due 2021 154 162 L+1.625 20 Utah Solar Portfolio, due 2022 273 278 various 13 Viento, due 2023 154 163 L+3.00 26 Walnut Creek, due 2023 235 267 L+1.625 82 Other 427 443 various 36 Subtotal project-level debt: 4,403 4,545 Total debt 5,856 6,068 Less current maturities (c) (868 ) (339 ) Less net debt issuance costs (56 ) (62 ) Total long-term debt $ 4,932 $ 5,667 (a) As of September 30, 2018 , L+ equals 3 month LIBOR plus x%, except for Viento, due 2023 where L+ equals 6 month LIBOR plus 3.00% and Utah Solar Portfolio, where L+ equals 1 month LIBOR plus x%. (b) Applicable rate is determined by the borrower leverage ratio, as defined in the credit agreement. (c) Current maturities reflect the results of the 2019 Convertible Notes and 2020 Convertible Notes tender offer, as further described below. 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 September 30, 2018 , the Company was in compliance with all of the required covenants. The discussion below describes material changes to or additions of long-term debt for the nine months ended September 30, 2018 . Clearway Energy LLC and Clearway Energy Operating LLC Revolving Credit Facility As of September 30, 2018 , there were no outstanding borrowings under the revolving credit facility and the Company had $70 million of letters of credit outstanding. On October 9, 2018, the Company terminated certain letters of credit relating to certain project PPAs in exchange for a one-time payment, which reduced the outstanding letters of credit under the revolving credit facility to $45 million as of October 31, 2018. On April 30, 2018, the Company closed on the refinancing of the revolving credit facility, which extended the maturity of the facility to April 28, 2023, and decreased the Company's overall cost of borrowing from L+ 2.50% to L+ 1.75% . The applicable rate is determined by the borrower leverage ratio, as defined in the credit agreement, and was L+ 1.50% as of September 30, 2018 . The facility will continue to be used for general corporate purposes including financing of future acquisitions and posting letters of credit. Bridge Credit Agreement On August 31, 2018, the Company entered into a senior unsecured 364-day bridge credit agreement, or the Bridge Credit Agreement, which provides total borrowings of up to a maximum amount of $1.5 billion at a rate per annum equal to LIBOR or a base rate plus an applicable margin equal to 3.00% in the case of LIBOR loans and 2.00% in the case of base rate loans, in each case subject to an additional 0.25% on the 90th day following the effective date of the Bridge Credit Agreement, 0.25% on the 180th day following such effective date and 0.50% on each 90th day thereafter while any loans remain outstanding. The obligation of the lenders to fund loans under the Bridge Credit Agreement will expire on the date that is 110 days after the effective date of the Bridge Credit Agreement. Loans under the Bridge Credit Agreement will mature 364 days after the effective date of the agreement, provided that Clearway Energy Operating LLC may elect in its sole discretion to extend the maturity as provided for in the Bridge Credit Agreement. Borrowings under the Bridge Credit Agreement are guaranteed by Clearway Energy LLC and certain subsidiaries of Clearway Energy Operating LLC. As of September 30, 2018, there were no borrowings under the Bridge Credit Agreement. In October 2018, the Company reduced the lenders' commitments under the bridge agreement from $1.5 billion to $867.5 million following the offering of the 2025 Senior Notes and the convertible notes tender offer results, each described below. On October 31, 2018, the Company terminated the Bridge Credit Agreement. 2025 Senior Notes On October 1, 2018, Clearway Energy Operating LLC issued $600 million of senior unsecured notes, or the 2025 Senior Notes. The 2025 Senior Notes bear interest at 5.750% and mature on October 15, 2025. Interest on the 2025 Senior Notes is payable semi-annually on April 15 and October 15 of each year, and interest payments will commence on April 15, 2019. The 2025 Senior Notes are unsecured obligations of Clearway Energy Operating LLC and are guaranteed by Clearway Energy LLC and by certain of Clearway Energy Operating LLC's wholly owned current and future subsidiaries. 2019 Convertible Notes Open Market Repurchases In August 2018, Clearway Energy, Inc. repurchased an aggregate principal amount of $16 million of the 2019 Convertible Notes in open market transactions. The repurchases were funded through a partial repayment of the intercompany note between Clearway Energy Operating LLC and Clearway Energy, Inc., which was reduced by $16 million . 2019 Convertible Notes and 2020 Convertible Notes Tender Offer On September 10, 2018, pursuant to the 2019 Convertible Notes and the 2020 Convertible Notes indentures, Clearway Energy, Inc. delivered to the holders of the 2019 Convertible Notes and the 2020 Convertible Notes a fundamental change notice and offer to repurchase any and all of the 2019 Convertible Notes and 2020 Convertible Notes for cash at a price equal to 100% of the principal amount of the Convertible Notes plus any accrued and unpaid interest. The tender offer expired on October 9, 2018. An aggregate principal amount of $109 million of the 2019 Convertible Notes and $243 million of the 2020 Convertible Notes were tendered on or prior to the expiration date and accepted by the Company for purchase. After the expiration of the tender offer, $216 million aggregate principal amount of the long-term debt - affiliate due 2019 remains outstanding and $44 million aggregate principal amount of the long-term debt - affiliate due 2020 remains outstanding. Project - level Debt Energy Center Minneapolis Series E, F, G, H Notes On June 19, 2018, Energy Center Minneapolis LLC, a subsidiary of the Company, entered into an amended and restated Thermal note purchase and private shelf agreement under which it authorized the issuance of the Series E Notes, Series F Notes, Series G Notes, and Series H Notes, as further described in the table below: (in millions) Amount Interest Rate Energy Center Minneapolis Series E Notes, due 2033 $ 70 4.80 % Energy Center Minneapolis Series F Notes, due 2033 10 4.60 % Energy Center Minneapolis Series G Notes, due 2035 83 5.90 % Energy Center Minneapolis Series H Notes, due 2037 40 4.83 % Total proceeds $ 203 Repayment of Energy Center Minneapolis Series C Notes, due 2025 (83 ) 5.95 % Net borrowings $ 120 The proceeds from the sale of the Series E Notes and the Series F Notes were utilized to finance the acquisition of the UPMC Thermal Project as described in Note 3 , Business Acquisitions . The Series G Notes were used to refinance the Series C Notes as noted above in the table. The Series H Notes were used to make a dividend to Clearway Energy Operating LLC. The amended and restated Thermal note purchase and private shelf agreement also established a private shelf facility for the future issuance of notes in the amount of $40 million . Buckthorn Solar Drop Down Asset Debt As part of the Buckthorn Solar Drop Down Asset acquisition, as further described in Note 3 , Business Acquisitions , the Company assumed non-recourse debt of $183 million relating to Buckthorn Solar Portfolio, LLC as of the date of the acquisition, March 30, 2018. The assumed debt consisted of a construction loan and an Investment Tax Credits, or ITC, bridge loan, both at an interest rate of LIBOR plus 1.75% . On May 31, 2018, $132 million of non-recourse debt was converted to a term loan with an expected maturity of May 2025, and the remainder of the non-recourse debt was repaid with the final contribution from the Class A member in the amount of $80 million upon the project reaching substantial completion in May 2018. Buckthorn Solar entered into a series of fixed for floating interest rate swaps that would fix the interest rate for a minimum of 80% of the outstanding notional amount. All interest rate swap payments by Buckthorn Solar and its counterparties are made quarterly and LIBOR is determined in advance of each interest period.

Segment Reporting

Segment Reporting	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Segment Reporting	Segment Reporting The Company’s segment structure reflects how management currently operates and allocates resources. The Company's businesses are 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, its Chief Executive Officer, evaluates the performance of its segments based on operational measures including adjusted earnings before interest, taxes, depreciation and amortization, or Adjusted EBITDA, and CAFD, as well as economic gross margin and net income (loss). Three months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 87 $ 152 $ 53 $ — $ 292 Cost of operations 12 39 33 — 84 Depreciation and amortization 26 52 6 — 84 General and administrative — — — 6 6 Acquisition-related transaction and integration costs — — — 17 17 Development costs — — — 1 1 Operating income (loss) 49 61 14 (24 ) 100 Equity in earnings of unconsolidated affiliates 3 29 — — 32 Other income, net — 1 — 1 2 Interest expense (13 ) (36 ) (4 ) (17 ) (70 ) Net Income (Loss) $ 39 $ 55 $ 10 $ (40 ) $ 64 Total Assets $ 1,811 $ 5,952 $ 512 $ 116 $ 8,391 Three months ended September 30, 2017 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 88 $ 135 $ 46 $ — $ 269 Cost of operations 16 34 29 — 79 Depreciation and amortization 27 58 5 — 90 Impairment losses — 12 — — 12 General and administrative — — — 4 4 Acquisition-related transaction and integration costs — — — — — Operating income (loss) 45 31 12 (4 ) 84 Equity in earnings of unconsolidated affiliates 3 25 — — 28 Other income, net 1 — — — 1 Interest expense (13 ) (38 ) (2 ) (18 ) (71 ) Net Income (Loss) $ 36 $ 18 $ 10 $ (22 ) $ 42 Nine months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 251 $ 427 $ 146 $ — $ 824 Cost of operations 44 106 97 — 247 Depreciation and amortization 76 154 17 — 247 General and administrative — — — 17 17 Acquisition-related transaction and integration costs — — — 19 19 Development costs — — — 1 1 Operating income (loss) 131 167 32 (37 ) 293 Equity in earnings of unconsolidated affiliates 8 57 — — 65 Other income, net 1 2 — 1 4 Interest expense (33 ) (95 ) (8 ) (54 ) (190 ) Net Income (Loss) $ 107 $ 131 $ 24 $ (90 ) $ 172 Total Assets $ 1,811 $ 5,952 $ 512 $ 116 $ 8,391 Nine months ended September 30, 2017 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 246 $ 402 $ 130 $ — $ 778 Cost of operations 53 102 86 — 241 Depreciation and amortization 77 154 15 — 246 Impairment losses — 12 — — 12 General and administrative — — — 14 14 Acquisition-related transaction and integration costs — — — 2 2 Operating income (loss) 116 134 29 (16 ) 263 Equity in earnings of unconsolidated affiliates 9 54 — — 63 Other income, net 1 1 — 1 3 Loss on debt extinguishment — (2 ) — — (2 ) Interest expense (39 ) (130 ) (7 ) (53 ) (229 ) Net Income (Loss) $ 87 $ 57 $ 22 $ (68 ) $ 98

Related Party Transactions

Related Party Transactions	9 Months Ended
	Sep. 30, 2018
Related Party Transactions [Abstract]
Related Party Transactions Disclosure	Related Party Transactions

Condensed Consolidating Financi

Condensed Consolidating Financial Information Condensed Consolidating Financial Information	9 Months Ended
	Sep. 30, 2018
Condensed Consolidating Financial Information Disclosure [Abstract]
Condensed Financial Statements [Text Block]	Condensed Consolidating Financial Information As of September 30, 2018 , Clearway Energy Operating LLC had outstanding $500 million of the 2024 Senior Notes and $350 million of the 2026 Senior Notes, collectively Senior Notes, as described in Note 10 , Long-term Debt to the consolidated financial statements included in the Company's 2017 Form 10-K. These Senior Notes are guaranteed by Clearway Energy LLC, 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 those 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 September 30, 2018 : Alta Wind 1-5 Holding Company, LLC Alta Wind Company, LLC Central CA Fuel Cell 1, LLC Clearway Energy LLC Clearway Energy Operating LLC Clearway Solar Star LLC DGPV Holding LLC Fuel Cell Holdings LLC Portfolio Solar I, LLC RPV Holding LLC Solar Flagstaff One LLC Solar Iguana LLC Solar Las Vegas MB 1 LLC Solar Tabernacle LLC South Trent Holdings LLC SPP Asset Holdings, LLC SPP Fund II Holdings, LLC SPP Fund II, LLC SPP Fund II-B, LLC SPP Fund III, LLC Thermal Canada Infrastructure Holdings LLC Thermal Infrastructure Development Holdings LLC UB Fuel Cell, LLC Clearway Energy Operating LLC conducts its business through and derives 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 Clearway Energy 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 Clearway Energy Operating LLC. However, there may be restrictions for certain non-guarantor subsidiaries. The following condensed consolidating financial information presents the financial information of Clearway Energy LLC, Clearway Energy 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, Clearway Energy LLC consists of parent company operations. Guarantor subsidiaries and non-guarantor subsidiaries of Clearway Energy 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. As described in Note 1 , Nature of Business , the Company completed the acquisitions of the Buckthorn Solar Drop Down Asset on March 30, 2018 and the November 2017 Drop Down Assets on November 1, 2017. 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 condensed consolidating financial statements to reflect the transfers as if they had taken place from the beginning of the financial statements period. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 3 $ 289 $ 1 $ (1 ) $ 292 Operating Costs and Expenses Cost of operations — — 84 1 (1 ) 84 Depreciation and amortization — 2 82 — — 84 General and administrative — — — 6 — 6 Acquisition-related transaction and integration costs — — — 17 — 17 Development costs — — — 1 — 1 Total operating costs and expenses — 2 166 25 (1 ) 192 Operating Income (Loss) — 1 123 (24 ) — 100 Other Income (Expense) Equity in earnings (losses) of consolidated affiliates 65 7 — 88 (160 ) — Equity in earnings of unconsolidated affiliates — 12 3 17 — 32 Other income, net 1 — 1 — — 2 Interest expense — — (52 ) (18 ) — (70 ) Total other income (expense), net 66 19 (48 ) 87 (160 ) (36 ) Net Income 66 20 75 63 (160 ) 64 Less: Net loss attributable to noncontrolling interests — — (2 ) (2 ) 2 (2 ) Net Income Attributable to Clearway Energy LLC $ 66 $ 20 $ 77 $ 65 $ (162 ) $ 66 (a) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Nine Months ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 9 $ 815 $ 2 $ (2 ) $ 824 Operating Costs and Expenses Cost of operations — 1 246 2 (2 ) 247 Depreciation and amortization — 4 243 — — 247 General and administrative — — — 17 — 17 Acquisition-related transaction and integration costs — — — 19 — 19 Development costs — — — 1 — 1 Total operating costs and expenses — 5 489 39 (2 ) 531 Operating Income (Loss) — 4 326 (37 ) — 293 Other Income (Expense) Equity in earnings of consolidated affiliates 266 19 — 236 (521 ) — Equity in earnings of unconsolidated affiliates — 32 7 26 — 65 Other income, net 1 — 3 — — 4 Interest expense — — (136 ) (54 ) — (190 ) Total other income (expense), net 267 51 (126 ) 208 (521 ) (121 ) Net Income 267 55 200 171 (521 ) 172 Less: Net loss attributable to noncontrolling interests — — (66 ) (95 ) 66 (95 ) Net Income Attributable to Clearway Energy LLC $ 267 $ 55 $ 266 $ 266 $ (587 ) $ 267 (a) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME For the Three Months Ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 66 $ 20 $ 75 $ 63 $ (160 ) $ 64 Other Comprehensive Income Unrealized gain on derivatives 7 — 8 7 (15 ) 7 Other comprehensive income 7 — 8 7 (15 ) 7 Comprehensive Income 73 20 83 70 (175 ) 71 Less: Comprehensive loss attributable to noncontrolling interests — — (2 ) (2 ) 2 (2 ) Comprehensive Income Attributable to Clearway Energy LLC $ 73 $ 20 $ 85 $ 72 $ (177 ) $ 73 For the Nine Months ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 267 $ 55 $ 200 $ 171 $ (521 ) $ 172 Other Comprehensive Income Unrealized gain on derivatives 34 1 30 34 (65 ) 34 Other comprehensive income 34 1 30 34 (65 ) 34 Comprehensive Income 301 56 230 205 (586 ) 206 Less: Comprehensive loss attributable to noncontrolling interests — — (66 ) (95 ) 66 (95 ) Comprehensive Income Attributable to Clearway Energy LLC $ 301 $ 56 $ 296 $ 300 $ (652 ) $ 301 (a) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated ASSETS (In millions) Current Assets Cash and cash equivalents $ 111 $ — $ 120 $ — $ — $ 231 Restricted cash — — 157 — — 157 Accounts receivable — trade — 3 138 — — 141 Inventory — — 39 — — 39 Notes receivable — — 3 — — 3 Prepayments and other current assets — — 29 2 — 31 Total current assets 111 3 486 2 — 602 Net property, plant and equipment 67 5,239 5,306 Other Assets Investment in consolidated subsidiaries 1,969 443 — 3,288 (5,700 ) — Equity investments in affiliates — 268 544 370 — 1,182 Intangible assets, net — 11 1,166 — — 1,177 Derivative instruments — — 32 — — 32 Other non-current assets — — 89 3 — 92 Total other assets 1,969 722 1,831 3,661 (5,700 ) 2,483 Total Assets $ 2,080 $ 792 $ 7,556 $ 3,663 $ (5,700 ) $ 8,391 (a) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS September 30, 2018 (Continued) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 309 $ — $ — $ 309 Current portion of long-term debt — affiliate — — — 559 — 559 Accounts payable — — 67 23 — 90 Accounts payable — affiliate — 1 10 11 — 22 Derivative instruments — — 5 — — 5 Accrued expenses and other current liabilities — — 80 15 — 95 Total current liabilities — 1 471 608 — 1,080 Other Liabilities Long-term debt — external — — 4,047 841 — 4,888 Long-term debt — affiliate — — — 44 — 44 Derivative instruments — — 9 — — 9 Other non-current liabilities — 2 87 8 — 97 Total non-current liabilities — 2 4,143 893 — 5,038 Total Liabilities — 3 4,614 1,501 — 6,118 Commitments and Contingencies Members' Equity Contributed capital 1,937 797 2,732 2,119 (5,648 ) 1,937 Retained earnings (accumulated deficit) 177 (8 ) 144 (116 ) (20 ) 177 Accumulated other comprehensive loss (34 ) — (41 ) (34 ) 75 (34 ) Noncontrolling interest — — 107 193 (107 ) 193 Total Members' Equity 2,080 789 2,942 2,162 (5,700 ) 2,273 Total Liabilities and Members’ Equity $ 2,080 $ 792 $ 7,556 $ 3,663 $ (5,700 ) $ 8,391 (a) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Nine Months ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Consolidated (In millions) Net Cash Provided by (Used in) Operating Activities $ — $ 9 $ 429 $ (41 ) $ 397 Cash Flows from Investing Activities Intercompany transactions between Clearway Energy LLC and subsidiaries 108 — — (108 ) — Acquisition of business, net of cash acquired — — — (11 ) (11 ) Payments for the Drop Down Assets — — — (126 ) (126 ) Capital expenditures — — (62 ) — (62 ) Cash receipts from notes receivable — — 10 — 10 Return of investment from unconsolidated affiliates — 7 11 4 22 Net investments in unconsolidated affiliates — (16 ) — — (16 ) Other — — 8 — 8 Net Cash Provided by (Used in) Investing Activities 108 (9 ) (33 ) (241 ) (175 ) Cash Flows from Financing Activities Transfer of funds under intercompany cash management arrangement 4 — (3 ) (1 ) — Net contributions from noncontrolling interests — — 98 10 108 (Payments of) proceeds from distributions (174 ) — (362 ) 347 (189 ) Payment of debt issuance costs — — (2 ) (3 ) (5 ) Proceeds from issuance of Class C units 151 — — — 151 Proceeds from the revolving credit facility — — — 35 35 Payments for the revolving credit facility — — — (90 ) (90 ) Proceeds from the issuance of long-term debt — external — — 227 — 227 Payments for long-term debt — external — — (369 ) — (369 ) Payments for long-term debt — affiliate — — — (16 ) (16 ) Net Cash (Used in) Provided by Financing Activities (19 ) — (411 ) 282 (148 ) Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash 89 — (15 ) — 74 Cash, Cash Equivalents and Restricted Cash at Beginning of Period 22 — 292 — 314 Cash, Cash Equivalents and Restricted Cash at End of Period $ 111 $ — $ 277 $ — $ 388 LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Eliminations (b) Consolidated (a) (In millions) Operating Revenues Total operating revenues $ — $ 3 $ 266 $ — $ — $ 269 Operating Costs and Expenses Cost of operations — — 79 — — 79 Depreciation and amortization — 2 88 — — 90 Impairment losses — 12 — — — 12 General and administrative — — — 4 — 4 Total operating costs and expenses — 14 167 4 — 185 Operating Income (Loss) — (11 ) 99 (4 ) — 84 Other Income (Expense) Equity in earnings of consolidated affiliates 65 (4 ) — 49 (110 ) — Equity in earnings of unconsolidated affiliates — 7 6 15 — 28 Other income, net — — 1 — — 1 Interest expense — — (53 ) (18 ) — (71 ) Total other income (expense), net 65 3 (46 ) 46 (110 ) (42 ) Net Income (Loss) 65 (8 ) 53 42 (110 ) 42 Less: Net loss attributable to noncontrolling interests — — (1 ) (23 ) 1 (23 ) Net Income (Loss) Attributable to Clearway Energy LLC $ 65 $ (8 ) $ 54 $ 65 $ (111 ) $ 65 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Nine Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Eliminations (b) Consolidated (a) (In millions) Operating Revenues Total operating revenues $ — $ 8 $ 770 $ 1 $ (1 ) $ 778 Operating Costs and Expenses Cost of operations — 1 240 1 (1 ) 241 Depreciation and amortization — 4 242 — — 246 Impairment losses — 12 — — — 12 General and administrative — — — 14 — 14 Acquisition-related transaction and integration costs — — — 2 — 2 Total operating costs and expenses — 17 482 17 (1 ) 515 Operating Income (Loss) — (9 ) 288 (16 ) — 263 Other Income (Expense) Equity in income of consolidated affiliates 153 6 — 141 (300 ) — Equity in earnings of unconsolidated affiliates — 9 28 26 — 63 Other income, net 1 — 2 — — 3 Loss on debt extinguishment — (2 ) — — — (2 ) Interest expense — 1 (176 ) (54 ) — (229 ) Total other income (expense), net 154 14 (146 ) 113 (300 ) (165 ) Net Income 154 5 142 97 (300 ) 98 Less: Net loss attributable to noncontrolling interests — — (3 ) (56 ) 3 (56 ) Net Income Attributable to Clearway Energy LLC $ 154 $ 5 $ 145 $ 153 $ (303 ) $ 154 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2017 Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (a) Eliminations (b) Consolidated (a) ASSETS (In millions) Current Assets Cash and cash equivalents $ 22 $ — $ 124 $ — $ — $ 146 Restricted cash — — 168 — — 168 Accounts receivable — trade — 1 93 1 — 95 Accounts receivable — affiliate 1 — — — — 1 Inventory — — 39 — — 39 Notes receivable — — 13 — — 13 Prepayments and other current assets — — 18 1 — 19 Total current assets 23 1 455 2 — 481 Net property, plant and equipment — 59 5,351 — — 5,410 Other Assets Investment in consolidated subsidiaries 1,844 460 — 3,198 (5,502 ) — Equity investments in affiliates — 233 577 368 — 1,178 Intangible assets, net — 12 1,216 — — 1,228 Derivative instruments — — 1 — — 1 Other non-current assets — — 62 — — 62 Total other assets 1,844 705 1,856 3,566 (5,502 ) 2,469 Total Assets $ 1,867 $ 765 $ 7,662 $ 3,568 $ (5,502 ) $ 8,360 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2017 (Continued) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (a) Eliminations (b) Consolidated (a) LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 339 $ — $ — $ 339 Accounts payable — — 46 — — 46 Accounts payable — affiliate — — 33 16 — 49 Derivative instruments — — 18 — — 18 Accrued expenses and other current liabilities — 62 25 — 87 Total current liabilities — — 498 41 — 539 Other Liabilities Long-term debt — external — — 4,153 896 — 5,049 Long-term debt — affiliate — — — 618 — 618 Derivative instruments — — 31 — — 31 Other non-current liabilities — 2 85 7 — 94 Total non-current liabilities — 2 4,269 1,521 — 5,792 Total Liabilities — 2 4,767 1,562 — 6,331 Commitments and Contingencies Members' Equity Contributed capital 1,919 822 2,934 2,119 (5,875 ) 1,919 Retained earnings (Accumulated deficit) 16 (58 ) (25 ) (207 ) 290 16 Accumulated other comprehensive loss (68 ) (1 ) (71 ) (68 ) 140 (68 ) Noncontrolling Interest — — 57 162 (57 ) 162 Total Members' Equity 1,867 763 2,895 2,006 (5,502 ) 2,029 Total Liabilities and Members’ Equity $ 1,867 $ 765 $ 7,662 $ 3,568 $ (5,502 ) $ 8,360 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Nine Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Consolidated (a) (In millions) Net Cash Provided by Operating Activities $ — $ 34 $ 417 $ (77 ) $ 374 Cash Flows from Investing Activities Intercompany transactions from Clearway Energy LLC to subsidiaries (13 ) — — 13 — Payments for the Drop Down Assets — — — (176 ) (176 ) Capital expenditures — — (102 ) — (102 ) Cash receipts from notes receivable — — 11 — 11 Return of investment from unconsolidated affiliates — 7 9 16 32 Net investments in unconsolidated affiliates — (41 ) (7 ) — (48 ) Net Cash Used in Investing Activities (13 ) (34 ) (89 ) (147 ) (283 ) Cash Flows from Financing Activities Transfer of funds under intercompany cash management arrangement (6 ) (1 ) — 7 — Net contributions from noncontrolling interests — — — 13 13 Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets — 25 (44 ) (7 ) (26 ) Proceeds from the issuance of Class C units 33 — — 33 (Payments of) proceeds from distributions (149 ) — (211 ) 211 (149 ) Payments of debt issuance costs — — (12 ) — (12 ) Proceeds from the issuance of long-term debt - external — — 130 — 130 Payments for long-term debt — external — (30 ) (225 ) — (255 ) Net Cash (Used in) Provided by Financing Activities (122 ) (6 ) (362 ) 224 (266 ) Net Decrease in Cash, Cash Equivalents and Restricted Cash (135 ) (6 ) (34 ) — (175 ) Cash, Cash Equivalents and Restricted Cash at Beginning of Period 211 9 277 — 497 Cash, Cash Equivalents and Restricted Cash at End of Period $ 76 $ 3 $ 243 $ — $ 322 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business .

Commitments and Contingencies (

Commitments and Contingencies (Notes)	9 Months Ended
	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies Disclosure [Text Block]	Contingencies This note should be read in conjunction with the complete description under Note 14 , Commitments and Contingencies , to the Company's 2017 Form 10-K. The Company's material legal proceedings are described below. The Company believes that it has valid defenses to these legal proceedings and intends to defend them vigorously. The Company records reserves for estimated losses from contingencies when information available indicates that a loss is probable and the amount of the loss, or range of loss, can be reasonably estimated. As applicable, the Company has established an adequate reserve for the matters discussed below. In addition, legal costs are expensed as incurred. Management assesses such matters based on current information and makes a judgment concerning its potential outcome, considering the nature of the claim, the amount and nature of damages sought, and the probability of success. The Company is unable to predict the outcome of the legal proceedings below or reasonably estimate the scope or amount of any associated costs and potential liabilities. As additional information becomes available, management adjusts its assessment and estimates of such contingencies accordingly. Because litigation is subject to inherent uncertainties and unfavorable rulings or developments, it is possible that the ultimate resolution of the Company's liabilities and contingencies could be at amounts that are different from its currently recorded reserves and that such difference could be material. In addition to the legal proceedings noted below, the Company and its subsidiaries are party to other litigation or legal proceedings arising in the ordinary course of business. In management's opinion, the disposition of these ordinary course matters will not materially adversely affect the Company's consolidated financial position, results of operations, or cash flows. Braun Litigation — On April 19, 2016, plaintiffs filed a putative class action lawsuit against NRG Yield, Inc., the current and former members of its board of directors individually, and other parties in California Superior Court in Kern County, California. Plaintiffs allege various violations of the Securities Act due to the defendants’ alleged failure to disclose material facts related to low wind production prior to the NRG Yield, Inc.'s June 22, 2015 Class C common stock offering. Plaintiffs seek compensatory damages, rescission, attorney’s fees and costs. The defendants filed demurrers and a motion challenging jurisdiction on October 18, 2016. On July 30, 2018, the plaintiffs filed an opposition to the defendants’ motion to quash service of the summons and an opposition to the defendants’ demurrer. On October 5, 2018, the defendants filed a reply memorandum of points and authorities in support of defendants' demurrer to the first amended complaint, and a reply memorandum of points and authorities in support of defendants' motion to quash service of summons. On November 1, 2018, the court issued a ruling granting the defendants' motion to quash service of summons.

Summary of Significant Accoun_2

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Policies)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Noncontrolling Interest Disclosure [Text Block]	Noncontrolling Interests Noncontrolling interests represent the equity associated with CEG's interest in Repowering Partnership LLC, as described in Note 4, Investments Accounted for by the Equity Method and Variable Interest Entities , and 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 tax credits. The following table reflects the changes in the Company's noncontrolling interest balance for the period from January 1, 2018 through September 30, 2018: (In millions) Balance as of December 31, 2017 $ 162 Capital contributions from tax equity investors, net of distributions (a) 108 Comprehensive loss (95 ) Contributions from CEG (b) 18 Balance as of September 30, 2018 $ 193 (a) Activity primarily relates
Distributions [Policy Text Block]	Distributions The following table lists the distributions paid on Clearway Energy LLC's Class A, B, C and D units during the nine months ended September 30, 2018 : Third Quarter 2018 Second Quarter 2018 First Quarter 2018 Distributions per Class A, B, C and D unit $ 0.320 $ 0.309 $ 0.298 On October 31, 2018 , Clearway Energy LLC declared a distribution on its Class A, Class B, Class C and Class D units of $0.331 per unit payable on December 17, 2018 to unit holders of record as of December 3, 2018 . Changes in Capital Structure At-the-Market Equity Offering Program, or the ATM Program Clearway Energy, Inc. is party to an equity distribution agreement with Barclays Capital Inc., Credit Suisse Securities (USA) LLC, J.P. Morgan Securities LLC and RBC Capital Markets, LLC, as sales agents. Pursuant to the terms of the equity distribution agreement, Clearway Energy, Inc. may offer and sell shares of its Class C common stock par value $0.01 per share, from time to time through the sales agents up to an aggregate sales price of $150 million through an at-the-market equity offering program, or the ATM Program. Clearway Energy, Inc. may also sell shares of its Class C common stock to any of the sales agents, as principals for its own account, at a price agreed upon at the time of sale. Clearway Energy, Inc. sold a total of 4,392,583 of Class C common stock for gross proceeds of $77 million during the period ended September 30, 2018 . Clearway Energy, Inc. used the net proceeds to acquire 4,392,583 Class C units from the Company. As of September 30, 2018 , approximately $38 million remains available for issuance under the ATM Program.
Use of Estimates	Use of Estimates The preparation of consolidated financial statements in accordance with GAAP requires management to make estimates and assumptions. These estimates and assumptions impact the reported amounts of assets and liabilities and disclosures of contingent assets and liabilities as of the date of the consolidated financial statements, and the reported amounts of revenues and expenses during the reporting period. Actual results could be different from these estimates.
Revenue Recognition, Policy [Policy Text Block]	Revenue Recognition Revenue from Contracts with Customers On January 1, 2018, the Company adopted the guidance in ASC 606, Revenue from Contracts with Customers, or Topic 606, using the modified retrospective method applied to contracts which were not completed as of the adoption date, with no adjustment required to the financial statements upon adoption. Following the adoption of the new standard, the Company’s revenue recognition of its contracts with customers remains materially consistent with its historical practice. The comparative information has not been restated and continues to be reported under the accounting standards in effect for those periods. The Company's policies with respect to its various revenue streams are detailed below. In general, the Company applies the invoicing practical expedient to recognize revenue for the revenue streams detailed below, except in circumstances where the invoiced amount does not represent the value transferred to the customer. Thermal Revenues Steam and chilled water revenue is recognized as the Company transfers the product to the customer, based on customer usage as determined by meter readings taken at month-end. Some locations read customer meters throughout the month, and recognize estimated revenue for the period between meter read date and month-end. For thermal contracts, the Company’s performance obligation to deliver steam and chilled water is satisfied over time and revenue is recognized based on the invoiced amount. The Thermal Business subsidiaries collect and remit state and local taxes associated with sales to their customers, as required by governmental authorities. These taxes are presented on a net basis in the income statement. As contracts for steam and chilled water are long-term contracts, the Company has performance obligations under these contracts that have not yet been satisfied. These performance obligations have transaction prices that are both fixed and variable, and that vary based on the contract duration, customer type, inception date and other contract-specific factors. For the fixed price contracts, the Company cannot accurately estimate the amount of its unsatisfied performance obligations as it will vary based on customer usage, which will depend on factors such as weather and customer activity. Power Purchase Agreements, or PPAs The majority of the Company’s revenues are obtained through PPAs or other contractual agreements. Energy, capacity and where applicable, renewable attributes, from the majority of the Company’s renewable energy assets and certain conventional energy plants is sold through long-term PPAs and tolling agreements to a single counterparty, which is often a utility or commercial customer. The majority of these PPAs are accounted for as leases. ASC 840 requires the minimum lease payments received to be amortized over the term of the lease and contingent rentals are recorded when the achievement of the contingency becomes probable. Judgment is required by management in determining the economic life of each generating facility, in evaluating whether certain lease provisions constitute minimum payments or represent contingent rent and other factors in determining whether a contract contains a lease and whether the lease is an operating lease or capital lease. Renewable Energy Credits, or RECs As stated above, renewable energy credits, or RECs, are usually sold through long-term PPAs. Revenue from the sale of self-generated RECs is recognized when the related energy is generated and simultaneously delivered even in cases where there is a certification lag as it has been deemed to be perfunctory. In a bundled contract to sell energy, capacity and/or self-generated RECs, all performance obligations are deemed to be delivered at the same time and hence, timing of recognition of revenue for all performance obligations is the same and occurs over time. In such cases, it is often unnecessary to allocate transaction price to multiple performance obligations. Sale of Emission Allowances The Company records its bank of emission allowances as part of intangible assets. From time to time, management may authorize the transfer of emission allowances in excess of usage from the Company's emission bank to intangible assets held-for-sale for trading purposes. The Company records the sale of emission allowances on a net basis within operating revenue in the Company's consolidated statements of operations. Disaggregated Revenues The following tables represent the Company’s disaggregation of revenue from contracts with customers for the three and nine months ended September 30, 2018 , along with the reportable segment for each category: Three months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Total Energy revenue (a) $ 2 $ 167 $ 50 $ 219 Capacity revenue (a) 86 — 4 90 Contract amortization (1 ) (15 ) (1 ) (17 ) Total operating revenue 87 152 53 292 Less: Lease revenue (88 ) (158 ) — (246 ) Less: Contract amortization 1 15 1 17 Total revenue from contracts with customers $ — $ 9 $ 54 $ 63 (a) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Total Energy Revenue $ 2 $ 158 $ 160 Capacity Revenue 86 — 86 88 158 246 Nine months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Total Energy revenue (b) $ 5 $ 473 $ 139 $ 617 Capacity revenue (b) 250 — 9 259 Contract amortization (4 ) (46 ) (2 ) (52 ) Total operating revenue 251 427 146 824 Less: Lease revenue (255 ) (438 ) (1 ) (694 ) Less: Contract amortization 4 46 2 52 Total revenue from contracts with customers $ — $ 35 $ 147 $ 182 (b) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Thermal Total Energy Revenue $ 5 $ 438 $ 1 $ 444 Capacity Revenue 250 — — 250 255 438 1 694 Contract Amortization Assets and liabilities recognized from power sales agreements assumed through acquisitions related to the sale of electric capacity and energy in future periods for which the fair value has been determined to be significantly less (more) than market are amortized to revenue over the term of each underlying contract based on actual generation and/or contracted volumes or on a straight-line basis, where applicable. Contract Balances The following table reflects the contract assets and liabilities included on the Company’s balance sheet as of September 30, 2018 : (In millions) September 30, 2018 Accounts receivable, net - Contracts with customers $ 35 Accounts receivable, net - Leases 106 Total accounts receivable, net $ 141
Recent Accounting Developments	Recent Accounting Developments - Not Yet Adopted ASU 2016-02 — In February 2016, the FASB issued ASU No. 2016-02, Leases (Topic 842), or Topic 842, with the objective to increase transparency and comparability among organizations by recognizing lease assets and lease liabilities on the balance sheet and to improve financial reporting by expanding the related disclosures. The guidance in Topic 842 provides that a lessee that may have previously accounted for a lease as an operating lease under current GAAP should recognize the assets and liabilities that arise from a lease on the balance sheet. In addition, Topic 842 expands the required quantitative and qualitative disclosures with regards to lease arrangements. The Company will adopt the standard effective January 1, 2019 and expects to elect certain of the practical expedients permitted, including the expedient that permits the Company to retain its existing lease assessment and classification. The Company is currently working through an adoption plan and evaluating the anticipated impact on the Company's results of operations, cash flows and financial position. While the Company is currently evaluating the impact the new guidance will have on its financial position and results of operations, the Company expects to recognize lease liabilities and right of use assets. The extent of the increase to assets and liabilities associated with these amounts remains to be determined pending the Company’s review of its existing lease contracts and service contracts which may contain embedded leases. While this review is still in process, the Company believes the adoption of Topic 842 may be material to its financial statements. The Company is continuing to monitor potential changes to Topic 842 that have been proposed by the FASB and will assess any necessary changes to the implementation as the guidance is updated.

Segment Reporting Segment Repor

Segment Reporting Segment Reporting (Policies)	9 Months Ended
	Sep. 30, 2018
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 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, its Chief Executive Officer, evaluates the performance of its segments based on operational measures including adjusted earnings before interest, taxes, depreciation and amortization, or Adjusted EBITDA, and CAFD, as well as economic gross margin and net income (loss).

Nature of Business Nature of Bu

Nature of Business Nature of Business (Tables)	9 Months Ended
	Sep. 30, 2018
Nature of Business Disclosure [Abstract]
IPO of NRG Yield [Table Text Block]	The following table represents the structure of the Company as of September 30, 2018 :
Schedule of Ownership [Table Text Block]	As of September 30, 2018 , the Company's operating assets are comprised of the following projects: Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration Conventional El Segundo 100 % 550 Southern California Edison 2023 GenConn Devon 50 % 95 Connecticut Light & Power 2040 GenConn Middletown 50 % 95 Connecticut Light & Power 2041 Marsh Landing 100 % 720 Pacific Gas and Electric 2023 Walnut Creek 100 % 485 Southern California Edison 2023 1,945 Utility Scale Solar Agua Caliente 16 % 46 Pacific Gas and Electric 2039 Alpine 100 % 66 Pacific Gas and Electric 2033 Avenal 50 % 23 Pacific Gas and Electric 2031 Avra Valley 100 % 26 Tucson Electric Power 2032 Blythe 100 % 21 Southern California Edison 2029 Borrego 100 % 26 San Diego Gas and Electric 2038 Buckthorn Solar 100 % 154 City of Georgetown, TX 2043 CVSR 100 % 250 Pacific Gas and Electric 2038 Desert Sunlight 250 25 % 63 Southern California Edison 2034 Desert Sunlight 300 25 % 75 Pacific Gas and Electric 2039 Kansas South 100 % 20 Pacific Gas and Electric 2033 Roadrunner 100 % 20 El Paso Electric 2031 Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration TA High Desert 100 % 20 Southern California Edison 2033 Utah Solar Portfolio (b) (e) 50 % 265 PacifiCorp 2036 1,075 Distributed Solar Apple I LLC Projects 100 % 9 Various 2032 AZ DG Solar Projects 100 % 5 Various 2025 - 2033 SPP Projects 100 % 25 Various 2026 - 2037 Other DG Projects 100 % 13 Various 2023 - 2039 52 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 Alta XI (b) 100 % 90 Southern California Edison 2038 Buffalo Bear 100 % 19 Western Farmers Electric Co-operative 2033 Crosswinds (b) (f) 99 % 21 Corn Belt Power Cooperative 2027 Elbow Creek (b) (f) 100 % 122 NRG Power Marketing LLC 2022 Elkhorn Ridge (b) (f) 66.7 % 54 Nebraska Public Power District 2029 Forward (b) (f) 100 % 29 Constellation NewEnergy, Inc. 2022 Goat Wind (b) (f) 100 % 150 Dow Pipeline Company 2025 Hardin (b) (f) 99 % 15 Interstate Power and Light Company 2027 Laredo Ridge 100 % 80 Nebraska Public Power District 2031 Lookout (b) (f) 100 % 38 Southern Maryland Electric Cooperative 2030 Odin (b) (f) 99.9 % 20 Missouri River Energy Services 2028 Pinnacle 100 % 55 Maryland Department of General Services and University System of Maryland 2031 San Juan Mesa (b) (f) 75 % 90 Southwestern Public Service Company 2025 Sleeping Bear (b) (f) 100 % 95 Public Service Company of Oklahoma 2032 South Trent 100 % 101 AEP Energy Partners 2029 Spanish Fork (b) (f) 100 % 19 PacifiCorp 2028 Spring Canyon II (b) 90.1 % 29 Platte River Power Authority 2039 Spring Canyon III (b) 90.1 % 25 Platte River Power Authority 2039 Taloga 100 % 130 Oklahoma Gas & Electric 2031 Wildorado (b) (f) 100 % 161 Southwestern Public Service Company 2027 2,200 Thermal Energy Center Dover LLC 100 % 103 NRG Power Marketing LLC 2018 Thermal generation 100 % 30 Various Various 133 Total net generation capacity (c) 5,405 Thermal equivalent MWt (d) 100 % 1,392 Various Various (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 September 30, 2018 . (b) Projects are part of tax equity arrangements . (c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs. (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. (e) Represents interests in Four Brothers Solar, LLC, Granite Mountain Holdings, LLC, and Iron Springs Holdings, LLC, all acquired as part of the March 2017 Drop Down Assets (ownership percentage is based upon cash to be distributed). (f) Projects are part of Wind TE Holdco portfolio.

Summary of Significant Accoun_3

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)	9 Months Ended
	Sep. 30, 2018
Accounting Policies [Abstract]
Schedule of Accumulated Depreciation and Amortization [Table Text Block]	Accumulated Depreciation, Accumulated Amortization The following table presents the accumulated depreciation included in the property, plant and equipment, net, and accumulated amortization included in intangible assets, net, respectively, as of September 30, 2018 and December 31, 2017 : September 30, 2018 December 31, 2017 (In millions) Property, Plant and Equipment Accumulated Depreciation $ 1,507 $ 1,285 Intangible Assets Accumulated Amortization 289 237
Schedule of Change in Noncontrolling Interest [Table Text Block]	Noncontrolling Interests Noncontrolling interests represent the equity associated with CEG's interest in Repowering Partnership LLC, as described in Note 4, Investments Accounted for by the Equity Method and Variable Interest Entities , and 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 tax credits. The following table reflects the changes in the Company's noncontrolling interest balance for the period from January 1, 2018 through September 30, 2018: (In millions) Balance as of December 31, 2017 $ 162 Capital contributions from tax equity investors, net of distributions (a) 108 Comprehensive loss (95 ) Contributions from CEG (b) 18 Balance as of September 30, 2018 $ 193
Distributions Made to Limited Liability Company (LLC) Member, by Distribution [Table Text Block]	Distributions The following table lists the distributions paid on Clearway Energy LLC's Class A, B, C and D units during the nine months ended September 30, 2018 : Third Quarter 2018 Second Quarter 2018 First Quarter 2018 Distributions per Class A, B, C and D unit $ 0.320 $ 0.309 $ 0.298 On October 31, 2018 , Clearway Energy LLC declared a distribution on its Class A, Class B, Class C and Class D units of $0.331 per unit payable on December 17, 2018 to unit holders of record as of December 3, 2018 .
Disaggregation of Revenue [Table Text Block]	The following tables represent the Company’s disaggregation of revenue from contracts with customers for the three and nine months ended September 30, 2018 , along with the reportable segment for each category: Three months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Total Energy revenue (a) $ 2 $ 167 $ 50 $ 219 Capacity revenue (a) 86 — 4 90 Contract amortization (1 ) (15 ) (1 ) (17 ) Total operating revenue 87 152 53 292 Less: Lease revenue (88 ) (158 ) — (246 ) Less: Contract amortization 1 15 1 17 Total revenue from contracts with customers $ — $ 9 $ 54 $ 63 (a) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Total Energy Revenue $ 2 $ 158 $ 160 Capacity Revenue 86 — 86 88 158 246 Nine months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Total Energy revenue (b) $ 5 $ 473 $ 139 $ 617 Capacity revenue (b) 250 — 9 259 Contract amortization (4 ) (46 ) (2 ) (52 ) Total operating revenue 251 427 146 824 Less: Lease revenue (255 ) (438 ) (1 ) (694 ) Less: Contract amortization 4 46 2 52 Total revenue from contracts with customers $ — $ 35 $ 147 $ 182 (b) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Thermal Total Energy Revenue $ 5 $ 438 $ 1 $ 444 Capacity Revenue 250 — — 250 255 438 1 694
Contract with Customer, Asset and Liability [Table Text Block]	The following table reflects the contract assets and liabilities included on the Company’s balance sheet as of September 30, 2018 : (In millions) September 30, 2018 Accounts receivable, net - Contracts with customers $ 35 Accounts receivable, net - Leases 106 Total accounts receivable, net $ 141

Business Acquisitions Busines_2

Business Acquisitions Business Acquisitions (Tables) - USD ($) $ in Millions	Mar. 31, 2018	Nov. 02, 2017	Sep. 30, 2018
November 2017 Drop Down Assets and August 2017 Drop Down Assets [Member]
Schedule of Business Acquisitions, by Acquisition [Table Text Block]			The following tables present a summary of the Company's historical information combining the financial information for the Buckthorn Solar Drop Down Asset and November 2017 Drop Down Assets transferred in connection with the acquisition: Three months ended September 30, 2017 As Previously Reported (a) Buckthorn Solar Drop Down Asset November 2017 Drop Down Assets As Currently Reported (In millions) Total operating revenues $ 265 $ — $ 4 $ 269 Operating income (loss) 95 — (11 ) 84 Net income (loss) 52 1 (11 ) 42 Less: Loss attributable to noncontrolling interests (23 ) — — (23 ) Net income (loss) attributable to Clearway Energy LLC 75 1 (11 ) 65 Nine months ended September 30, 2017 As Previously Reported (a) Buckthorn Solar Drop Down Asset November 2017 Drop Down Assets As Currently Reported (In millions) Total operating revenues $ 767 $ — $ 11 $ 778 Operating income 271 — (8 ) 263 Net income (loss) 110 (2 ) (10 ) 98 Less: Loss attributable to noncontrolling interests (56 ) — — (56 ) Net income (loss) attributable to Clearway Energy LLC 166 (2 ) (10 ) 154 (a) As previously reported in the Company's Form 10-Q for the quarter ended September 30, 2017.
Buckthorn Solar Drop Down Asset [Member]
Business Combination, Consideration Transferred	$ 42
Schedule of Business Acquisitions, by Acquisition [Table Text Block]			The following is a summary of net assets transferred in connection with the acquisition of the Buckthorn Solar Drop Down Asset as of March 31, 2018: (In millions) Assets: Current assets $ 20 Property, plant and equipment 212 Non-current assets 3 Total assets 235 Liabilities: Debt (Current and non-current) (a) 176 Other current and non-current liabilities 15 Total liabilities 191 Less: noncontrolling interest 19 Net assets acquired $ 25 (a) Net of $7 million of net debt issuance costs.
November 2017 Drop Down Assets [Member]
Business Combination, Consideration Transferred		$ 74

Variable Interest Entities (Tab

Variable Interest Entities (Tables)	9 Months Ended
	Sep. 30, 2018
Schedule of Equity Method Investments [Line Items]
Equity Method Investments [Table Text Block]
Entities that are not consolidated [Member]
Schedule of Equity Method Investments [Line Items]
Schedule of Variable Interest Entities [Table Text Block]	The Company's maximum exposure to loss as of September 30, 2018 , is limited to its equity investment in the unconsolidated entities, as further summarized in the table below: (In millions) Maximum exposure to loss Four Brothers Solar, LLC $ 204 GenConn Energy LLC 98 DGPV Holdco 3 LLC 85 DGPV Holdco 1 LLC 78 Granite Mountain Holdings, LLC 74 DGPV Holdco 2 LLC 63 Iron Springs Holdings, LLC 52 RPV Holdco 1 LLC 42
Consolidated Entities [Member]
Schedule of Equity Method Investments [Line Items]
Schedule of Variable Interest Entities [Table Text Block]	Summarized financial information for the Company's consolidated VIEs consisted of the following as of September 30, 2018 : (In millions) Wind TE Holdco Alta Wind TE Holdco Spring Canyon Buckthorn Renewables, LLC Other current and non-current assets $ 192 $ 32 $ 1 $ 21 Property, plant and equipment 354 417 92 225 Intangible assets 2 253 — — Total assets 548 702 93 246 Current and non-current liabilities 205 14 5 136 Total liabilities 205 14 5 136 Noncontrolling interest 32 67 50 44 Net assets less noncontrolling interests $ 311 $ 621 $ 38 $ 66

Fair Value of Financial Instr_2

Fair Value of Financial Instruments (Tables)	9 Months Ended
	Sep. 30, 2018
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
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 September 30, 2018 As of December 31, 2017 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Assets: Notes receivable $ 3 $ 3 $ 13 $ 13 Liabilities: Long-term debt — affiliate, including current portion 603 603 618 618 Long-term debt — external, including current portion (a) $ 5,253 $ 5,218 $ 5,450 $ 5,466 (a) Excludes deferred financing costs, which are recorded as a reduction to long-term debt on the Company's consolidated balance sheets.
Fair Value Option, Disclosures [Table Text Block]	The fair value of the Company's publicly-traded long-term debt is based on quoted market prices and is classified as Level 2 within the fair value hierarchy. The fair value of non-publicly traded long-term debt and certain notes receivable of the Company are based on expected future cash flows discounted at market interest rates, or current interest rates for similar instruments with equivalent credit quality and are classified as Level 3 within the fair value hierarchy. The following table presents the level within the fair value hierarchy for long-term debt, including current portion as of September 30, 2018 and December 31, 2017 : As of September 30, 2018 As of December 31, 2017 Level 2 Level 3 Level 2 Level 3 (In millions) Long-term debt, including current portion $ 834 $ 4,987 $ 870 $ 5,214
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	The Company records its derivative assets and liabilities at fair 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 September 30, 2018 As of December 31, 2017 Fair Value (a) Fair Value (a) (In millions) Level 2 Level 2 Derivative assets: Commodity contracts $ — $ 1 Interest rate contracts 35 1 Total assets 35 2 Derivative liabilities: Commodity contracts 1 1 Interest rate contracts 13 48 Total liabilities $ 14 $ 49 (a) There were no derivative assets or liabilities classified as Level 1 or Level 3 as of September 30, 2018 and December 31, 2017 .

Accounting for Derivative Ins_2

Accounting for Derivative Instruments and Hedging Activities (Tables)	9 Months Ended
	Sep. 30, 2018
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 of the Company's open derivative transactions broken out by type: Total Volume September 30, 2018 December 31, 2017 Commodity Units (In millions) Natural Gas MMBtu 2 2 Interest Dollars $ 1,909 $ 2,050
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 (a) Derivative Liabilities September 30, 2018 December 31, 2017 September 30, 2018 December 31, 2017 (In millions) Derivatives Designated as Cash Flow Hedges: Interest rate contracts current $ 2 $ — $ 1 $ 4 Interest rate contracts long-term 11 1 4 9 Total Derivatives Designated as Cash Flow Hedges 13 1 5 13 Derivatives Not Designated as Cash Flow Hedges : Interest rate contracts current 1 — 3 13 Interest rate contracts long-term 21 — 5 22 Commodity contracts current — 1 1 1 Total Derivatives Not Designated as Cash Flow Hedges 22 1 9 36 Total Derivatives $ 35 $ 2 $ 14 $ 49 (a) Derivative Assets balances classified as current are included within the prepayments and other current assets line item of the consolidated balance sheets as of September 30, 2018 and December 31, 2017 .
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 September 30, 2018 and December 31, 2017 , there was no outstanding collateral paid or received. The following tables summarize the offsetting of derivatives by the counterparty master agreement level as of September 30, 2018 and December 31, 2017 : As of September 30, 2018 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts (a) : (In millions) Derivative liabilities $ (1 ) $ — $ (1 ) Total commodity contracts (1 ) — (1 ) Interest rate contracts: Derivative assets 35 (2 ) 33 Derivative liabilities (13 ) 2 (11 ) Total interest rate contracts 22 — 22 Total derivative instruments $ 21 $ — $ 21 (a) There were no commodity contracts classified as derivative assets as of September 30, 2018 . As of December 31, 2017 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ 1 $ — $ 1 Derivative liabilities (1 ) — (1 ) Total commodity contracts — — — Interest rate contracts: Derivative assets 1 (1 ) — Derivative liabilities (48 ) 1 (47 ) Total interest rate contracts (47 ) — (47 ) Total derivative instruments $ (47 ) $ — $ (47 )
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 September 30, Nine months ended September 30, 2018 2017 2018 2017 (In millions) Accumulated OCL beginning balance $ (42 ) $ (86 ) $ (69 ) $ (86 ) Reclassified from accumulated OCL to income due to realization of previously deferred amounts 5 5 13 13 Mark-to-market of cash flow hedge accounting contracts 2 2 21 (6 ) Accumulated OCL ending balance (35 ) (79 ) (35 ) (79 ) Accumulated OCL attributable to noncontrolling interests (1 ) (1 ) (1 ) (1 ) Accumulated OCL attributable to Clearway Energy LLC $ (34 ) $ (78 ) $ (34 ) $ (78 ) Losses expected to be realized from OCL during the next 12 months $ (9 ) $ (9 )

Long-term Debt (Tables)

Long-term Debt (Tables)	9 Months Ended
	Sep. 30, 2018
Debt Instrument [Line Items]
Schedule of long-term debt	This footnote should be read in conjunction with the complete description under Note 10 , Long-term Debt , to the consolidated financial statements included in the Company's 2017 Form 10-K. Long-term debt consisted of the following: September 30, 2018 December 31, 2017 September 30, 2018, interest rate % (a) Letters of Credit Outstanding at September 30, 2018 (In millions, except rates) Long-term debt - affiliate, due 2019 $ 322 $ 337 3.580 $ — Long-term debt - affiliate, due 2020 281 281 3.325 — 2024 Senior Notes 500 500 5.375 — 2026 Senior Notes 350 350 5.000 — Clearway Energy LLC and Clearway Energy Operating LLC Revolving Credit Facility, due 2023 (b) — 55 L+1.50 70 Project-level debt: Agua Caliente Borrower 2, due 2038 39 41 5.430 17 Alpine, due 2022 129 135 L+1.750 16 Alta Wind I - V lease financing arrangements, due 2034 and 2035 901 926 5.696 - 7.015 103 Buckthorn Solar, due 2025 132 169 L+1.750 26 CVSR, due 2037 720 746 2.339 - 3.775 — CVSR Holdco Notes, due 2037 188 194 4.680 13 El Segundo Energy Center, due 2023 352 400 L+1.75 - L+2.375 138 Energy Center Minneapolis Series C Notes, due 2025 — 83 5.950 — Energy Center Minneapolis Series D Notes, due 2031 125 125 3.550 — Energy Center Minneapolis Series E, F, G, H Notes 203 — various — Laredo Ridge, due 2028 91 95 L+1.875 10 Marsh Landing, due 2023 280 318 L+2.125 38 Tapestry, due 2021 154 162 L+1.625 20 Utah Solar Portfolio, due 2022 273 278 various 13 Viento, due 2023 154 163 L+3.00 26 Walnut Creek, due 2023 235 267 L+1.625 82 Other 427 443 various 36 Subtotal project-level debt: 4,403 4,545 Total debt 5,856 6,068 Less current maturities (c) (868 ) (339 ) Less net debt issuance costs (56 ) (62 ) Total long-term debt $ 4,932 $ 5,667 (a) As of September 30, 2018 , L+ equals 3 month LIBOR plus x%, except for Viento, due 2023 where L+ equals 6 month LIBOR plus 3.00% and Utah Solar Portfolio, where L+ equals 1 month LIBOR plus x%. (b) Applicable rate is determined by the borrower leverage ratio, as defined in the credit agreement. (c) Current maturities reflect the results of the 2019 Convertible Notes and 2020 Convertible Notes tender offer, as further described below.
Energy Center Minneapolis Series E, F, G, H Notes [Member]
Debt Instrument [Line Items]
Schedule of Long-term Debt Instruments [Table Text Block]	On June 19, 2018, Energy Center Minneapolis LLC, a subsidiary of the Company, entered into an amended and restated Thermal note purchase and private shelf agreement under which it authorized the issuance of the Series E Notes, Series F Notes, Series G Notes, and Series H Notes, as further described in the table below: (in millions) Amount Interest Rate Energy Center Minneapolis Series E Notes, due 2033 $ 70 4.80 % Energy Center Minneapolis Series F Notes, due 2033 10 4.60 % Energy Center Minneapolis Series G Notes, due 2035 83 5.90 % Energy Center Minneapolis Series H Notes, due 2037 40 4.83 % Total proceeds $ 203 Repayment of Energy Center Minneapolis Series C Notes, due 2025 (83 ) 5.95 % Net borrowings $ 120

Segment Reporting (Tables)

Segment Reporting (Tables)	9 Months Ended
	Sep. 30, 2018
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Three months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 87 $ 152 $ 53 $ — $ 292 Cost of operations 12 39 33 — 84 Depreciation and amortization 26 52 6 — 84 General and administrative — — — 6 6 Acquisition-related transaction and integration costs — — — 17 17 Development costs — — — 1 1 Operating income (loss) 49 61 14 (24 ) 100 Equity in earnings of unconsolidated affiliates 3 29 — — 32 Other income, net — 1 — 1 2 Interest expense (13 ) (36 ) (4 ) (17 ) (70 ) Net Income (Loss) $ 39 $ 55 $ 10 $ (40 ) $ 64 Total Assets $ 1,811 $ 5,952 $ 512 $ 116 $ 8,391 Three months ended September 30, 2017 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 88 $ 135 $ 46 $ — $ 269 Cost of operations 16 34 29 — 79 Depreciation and amortization 27 58 5 — 90 Impairment losses — 12 — — 12 General and administrative — — — 4 4 Acquisition-related transaction and integration costs — — — — — Operating income (loss) 45 31 12 (4 ) 84 Equity in earnings of unconsolidated affiliates 3 25 — — 28 Other income, net 1 — — — 1 Interest expense (13 ) (38 ) (2 ) (18 ) (71 ) Net Income (Loss) $ 36 $ 18 $ 10 $ (22 ) $ 42 Nine months ended September 30, 2018 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 251 $ 427 $ 146 $ — $ 824 Cost of operations 44 106 97 — 247 Depreciation and amortization 76 154 17 — 247 General and administrative — — — 17 17 Acquisition-related transaction and integration costs — — — 19 19 Development costs — — — 1 1 Operating income (loss) 131 167 32 (37 ) 293 Equity in earnings of unconsolidated affiliates 8 57 — — 65 Other income, net 1 2 — 1 4 Interest expense (33 ) (95 ) (8 ) (54 ) (190 ) Net Income (Loss) $ 107 $ 131 $ 24 $ (90 ) $ 172 Total Assets $ 1,811 $ 5,952 $ 512 $ 116 $ 8,391 Nine months ended September 30, 2017 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 246 $ 402 $ 130 $ — $ 778 Cost of operations 53 102 86 — 241 Depreciation and amortization 77 154 15 — 246 Impairment losses — 12 — — 12 General and administrative — — — 14 14 Acquisition-related transaction and integration costs — — — 2 2 Operating income (loss) 116 134 29 (16 ) 263 Equity in earnings of unconsolidated affiliates 9 54 — — 63 Other income, net 1 1 — 1 3 Loss on debt extinguishment — (2 ) — — (2 ) Interest expense (39 ) (130 ) (7 ) (53 ) (229 ) Net Income (Loss) $ 87 $ 57 $ 22 $ (68 ) $ 98

Condensed Consolidating Finan_2

Condensed Consolidating Financial Information Condensed Consolidating Financial Information (Tables)	9 Months Ended
	Sep. 30, 2018
Condensed Consolidating Financial Information Disclosure [Abstract]
Condensed Income Statement [Table Text Block]	LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 3 $ 289 $ 1 $ (1 ) $ 292 Operating Costs and Expenses Cost of operations — — 84 1 (1 ) 84 Depreciation and amortization — 2 82 — — 84 General and administrative — — — 6 — 6 Acquisition-related transaction and integration costs — — — 17 — 17 Development costs — — — 1 — 1 Total operating costs and expenses — 2 166 25 (1 ) 192 Operating Income (Loss) — 1 123 (24 ) — 100 Other Income (Expense) Equity in earnings (losses) of consolidated affiliates 65 7 — 88 (160 ) — Equity in earnings of unconsolidated affiliates — 12 3 17 — 32 Other income, net 1 — 1 — — 2 Interest expense — — (52 ) (18 ) — (70 ) Total other income (expense), net 66 19 (48 ) 87 (160 ) (36 ) Net Income 66 20 75 63 (160 ) 64 Less: Net loss attributable to noncontrolling interests — — (2 ) (2 ) 2 (2 ) Net Income Attributable to Clearway Energy LLC $ 66 $ 20 $ 77 $ 65 $ (162 ) $ 66 (a) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Nine Months ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Operating Revenues Total operating revenues $ — $ 9 $ 815 $ 2 $ (2 ) $ 824 Operating Costs and Expenses Cost of operations — 1 246 2 (2 ) 247 Depreciation and amortization — 4 243 — — 247 General and administrative — — — 17 — 17 Acquisition-related transaction and integration costs — — — 19 — 19 Development costs — — — 1 — 1 Total operating costs and expenses — 5 489 39 (2 ) 531 Operating Income (Loss) — 4 326 (37 ) — 293 Other Income (Expense) Equity in earnings of consolidated affiliates 266 19 — 236 (521 ) — Equity in earnings of unconsolidated affiliates — 32 7 26 — 65 Other income, net 1 — 3 — — 4 Interest expense — — (136 ) (54 ) — (190 ) Total other income (expense), net 267 51 (126 ) 208 (521 ) (121 ) Net Income 267 55 200 171 (521 ) 172 Less: Net loss attributable to noncontrolling interests — — (66 ) (95 ) 66 (95 ) Net Income Attributable to Clearway Energy LLC $ 267 $ 55 $ 266 $ 266 $ (587 ) $ 267 (a) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Three Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Eliminations (b) Consolidated (a) (In millions) Operating Revenues Total operating revenues $ — $ 3 $ 266 $ — $ — $ 269 Operating Costs and Expenses Cost of operations — — 79 — — 79 Depreciation and amortization — 2 88 — — 90 Impairment losses — 12 — — — 12 General and administrative — — — 4 — 4 Total operating costs and expenses — 14 167 4 — 185 Operating Income (Loss) — (11 ) 99 (4 ) — 84 Other Income (Expense) Equity in earnings of consolidated affiliates 65 (4 ) — 49 (110 ) — Equity in earnings of unconsolidated affiliates — 7 6 15 — 28 Other income, net — — 1 — — 1 Interest expense — — (53 ) (18 ) — (71 ) Total other income (expense), net 65 3 (46 ) 46 (110 ) (42 ) Net Income (Loss) 65 (8 ) 53 42 (110 ) 42 Less: Net loss attributable to noncontrolling interests — — (1 ) (23 ) 1 (23 ) Net Income (Loss) Attributable to Clearway Energy LLC $ 65 $ (8 ) $ 54 $ 65 $ (111 ) $ 65 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF OPERATIONS For the Nine Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Eliminations (b) Consolidated (a) (In millions) Operating Revenues Total operating revenues $ — $ 8 $ 770 $ 1 $ (1 ) $ 778 Operating Costs and Expenses Cost of operations — 1 240 1 (1 ) 241 Depreciation and amortization — 4 242 — — 246 Impairment losses — 12 — — — 12 General and administrative — — — 14 — 14 Acquisition-related transaction and integration costs — — — 2 — 2 Total operating costs and expenses — 17 482 17 (1 ) 515 Operating Income (Loss) — (9 ) 288 (16 ) — 263 Other Income (Expense) Equity in income of consolidated affiliates 153 6 — 141 (300 ) — Equity in earnings of unconsolidated affiliates — 9 28 26 — 63 Other income, net 1 — 2 — — 3 Loss on debt extinguishment — (2 ) — — — (2 ) Interest expense — 1 (176 ) (54 ) — (229 ) Total other income (expense), net 154 14 (146 ) 113 (300 ) (165 ) Net Income 154 5 142 97 (300 ) 98 Less: Net loss attributable to noncontrolling interests — — (3 ) (56 ) 3 (56 ) Net Income Attributable to Clearway Energy LLC $ 154 $ 5 $ 145 $ 153 $ (303 ) $ 154 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation.
Condensed Statement of Comprehensive Income [Table Text Block]	CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME For the Three Months Ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 66 $ 20 $ 75 $ 63 $ (160 ) $ 64 Other Comprehensive Income Unrealized gain on derivatives 7 — 8 7 (15 ) 7 Other comprehensive income 7 — 8 7 (15 ) 7 Comprehensive Income 73 20 83 70 (175 ) 71 Less: Comprehensive loss attributable to noncontrolling interests — — (2 ) (2 ) 2 (2 ) Comprehensive Income Attributable to Clearway Energy LLC $ 73 $ 20 $ 85 $ 72 $ (177 ) $ 73 For the Nine Months ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated (In millions) Net Income $ 267 $ 55 $ 200 $ 171 $ (521 ) $ 172 Other Comprehensive Income Unrealized gain on derivatives 34 1 30 34 (65 ) 34 Other comprehensive income 34 1 30 34 (65 ) 34 Comprehensive Income 301 56 230 205 (586 ) 206 Less: Comprehensive loss attributable to noncontrolling interests — — (66 ) (95 ) 66 (95 ) Comprehensive Income Attributable to Clearway Energy LLC $ 301 $ 56 $ 296 $ 300 $ (652 ) $ 301 (a) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF COMPREHENSIVE INCOME (LOSS) For the Three Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Eliminations (b) Consolidated (a) (In millions) Net Income $ 65 $ (8 ) $ 53 $ 42 $ (110 ) $ 42 Other Comprehensive Income Unrealized loss on derivatives 7 — 7 7 (14 ) 7 Other comprehensive income 7 — 7 7 (14 ) 7 Comprehensive Income (Loss) 72 (8 ) 60 49 (124 ) 49 Less: Comprehensive loss attributable to noncontrolling interests — — (1 ) (23 ) 1 (23 ) Comprehensive Income (Loss) Attributable to Clearway Energy LLC $ 72 $ (8 ) $ 61 $ 72 $ (125 ) $ 72 For the Nine Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Eliminations (b) Consolidated (a) (In millions) Net Income $ 154 $ 5 $ 142 $ 97 $ (300 ) $ 98 Other Comprehensive Income Unrealized gain on derivatives 7 — 7 7 (14 ) 7 Other comprehensive income 7 — 7 7 (14 ) 7 Comprehensive Income 161 5 149 104 (314 ) 105 Less: Comprehensive loss attributable to noncontrolling interests — — (3 ) (56 ) 3 (56 ) Comprehensive Income Attributable to Clearway Energy LLC $ 161 $ 5 $ 152 $ 160 $ (317 ) $ 161 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation.
Condensed Balance Sheet [Table Text Block]	LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated ASSETS (In millions) Current Assets Cash and cash equivalents $ 111 $ — $ 120 $ — $ — $ 231 Restricted cash — — 157 — — 157 Accounts receivable — trade — 3 138 — — 141 Inventory — — 39 — — 39 Notes receivable — — 3 — — 3 Prepayments and other current assets — — 29 2 — 31 Total current assets 111 3 486 2 — 602 Net property, plant and equipment 67 5,239 5,306 Other Assets Investment in consolidated subsidiaries 1,969 443 — 3,288 (5,700 ) — Equity investments in affiliates — 268 544 370 — 1,182 Intangible assets, net — 11 1,166 — — 1,177 Derivative instruments — — 32 — — 32 Other non-current assets — — 89 3 — 92 Total other assets 1,969 722 1,831 3,661 (5,700 ) 2,483 Total Assets $ 2,080 $ 792 $ 7,556 $ 3,663 $ (5,700 ) $ 8,391 (a) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS September 30, 2018 (Continued) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Eliminations (a) Consolidated LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 309 $ — $ — $ 309 Current portion of long-term debt — affiliate — — — 559 — 559 Accounts payable — — 67 23 — 90 Accounts payable — affiliate — 1 10 11 — 22 Derivative instruments — — 5 — — 5 Accrued expenses and other current liabilities — — 80 15 — 95 Total current liabilities — 1 471 608 — 1,080 Other Liabilities Long-term debt — external — — 4,047 841 — 4,888 Long-term debt — affiliate — — — 44 — 44 Derivative instruments — — 9 — — 9 Other non-current liabilities — 2 87 8 — 97 Total non-current liabilities — 2 4,143 893 — 5,038 Total Liabilities — 3 4,614 1,501 — 6,118 Commitments and Contingencies Members' Equity Contributed capital 1,937 797 2,732 2,119 (5,648 ) 1,937 Retained earnings (accumulated deficit) 177 (8 ) 144 (116 ) (20 ) 177 Accumulated other comprehensive loss (34 ) — (41 ) (34 ) 75 (34 ) Noncontrolling interest — — 107 193 (107 ) 193 Total Members' Equity 2,080 789 2,942 2,162 (5,700 ) 2,273 Total Liabilities and Members’ Equity $ 2,080 $ 792 $ 7,556 $ 3,663 $ (5,700 ) $ 8,391 (a) All significant intercompany transactions have been eliminated in consolidation. LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2017 Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (a) Eliminations (b) Consolidated (a) ASSETS (In millions) Current Assets Cash and cash equivalents $ 22 $ — $ 124 $ — $ — $ 146 Restricted cash — — 168 — — 168 Accounts receivable — trade — 1 93 1 — 95 Accounts receivable — affiliate 1 — — — — 1 Inventory — — 39 — — 39 Notes receivable — — 13 — — 13 Prepayments and other current assets — — 18 1 — 19 Total current assets 23 1 455 2 — 481 Net property, plant and equipment — 59 5,351 — — 5,410 Other Assets Investment in consolidated subsidiaries 1,844 460 — 3,198 (5,502 ) — Equity investments in affiliates — 233 577 368 — 1,178 Intangible assets, net — 12 1,216 — — 1,228 Derivative instruments — — 1 — — 1 Other non-current assets — — 62 — — 62 Total other assets 1,844 705 1,856 3,566 (5,502 ) 2,469 Total Assets $ 1,867 $ 765 $ 7,662 $ 3,568 $ (5,502 ) $ 8,360 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation. CLEARWAY ENERGY LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING BALANCE SHEETS December 31, 2017 (Continued) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (a) Eliminations (b) Consolidated (a) LIABILITIES AND MEMBERS' EQUITY (In millions) Current Liabilities Current portion of long-term debt — external $ — $ — $ 339 $ — $ — $ 339 Accounts payable — — 46 — — 46 Accounts payable — affiliate — — 33 16 — 49 Derivative instruments — — 18 — — 18 Accrued expenses and other current liabilities — 62 25 — 87 Total current liabilities — — 498 41 — 539 Other Liabilities Long-term debt — external — — 4,153 896 — 5,049 Long-term debt — affiliate — — — 618 — 618 Derivative instruments — — 31 — — 31 Other non-current liabilities — 2 85 7 — 94 Total non-current liabilities — 2 4,269 1,521 — 5,792 Total Liabilities — 2 4,767 1,562 — 6,331 Commitments and Contingencies Members' Equity Contributed capital 1,919 822 2,934 2,119 (5,875 ) 1,919 Retained earnings (Accumulated deficit) 16 (58 ) (25 ) (207 ) 290 16 Accumulated other comprehensive loss (68 ) (1 ) (71 ) (68 ) 140 (68 ) Noncontrolling Interest — — 57 162 (57 ) 162 Total Members' Equity 1,867 763 2,895 2,006 (5,502 ) 2,029 Total Liabilities and Members’ Equity $ 1,867 $ 765 $ 7,662 $ 3,568 $ (5,502 ) $ 8,360 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business . (b) All significant intercompany transactions have been eliminated in consolidation.
Condensed Cash Flow Statement [Table Text Block]	LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Nine Months ended September 30, 2018 (Unaudited) Clearway Energy LLC Other Guarantor Subsidiaries Non-Guarantor Subsidiaries Clearway Energy Operating LLC (Note Issuer) Consolidated (In millions) Net Cash Provided by (Used in) Operating Activities $ — $ 9 $ 429 $ (41 ) $ 397 Cash Flows from Investing Activities Intercompany transactions between Clearway Energy LLC and subsidiaries 108 — — (108 ) — Acquisition of business, net of cash acquired — — — (11 ) (11 ) Payments for the Drop Down Assets — — — (126 ) (126 ) Capital expenditures — — (62 ) — (62 ) Cash receipts from notes receivable — — 10 — 10 Return of investment from unconsolidated affiliates — 7 11 4 22 Net investments in unconsolidated affiliates — (16 ) — — (16 ) Other — — 8 — 8 Net Cash Provided by (Used in) Investing Activities 108 (9 ) (33 ) (241 ) (175 ) Cash Flows from Financing Activities Transfer of funds under intercompany cash management arrangement 4 — (3 ) (1 ) — Net contributions from noncontrolling interests — — 98 10 108 (Payments of) proceeds from distributions (174 ) — (362 ) 347 (189 ) Payment of debt issuance costs — — (2 ) (3 ) (5 ) Proceeds from issuance of Class C units 151 — — — 151 Proceeds from the revolving credit facility — — — 35 35 Payments for the revolving credit facility — — — (90 ) (90 ) Proceeds from the issuance of long-term debt — external — — 227 — 227 Payments for long-term debt — external — — (369 ) — (369 ) Payments for long-term debt — affiliate — — — (16 ) (16 ) Net Cash (Used in) Provided by Financing Activities (19 ) — (411 ) 282 (148 ) Net Increase (Decrease) in Cash, Cash Equivalents and Restricted Cash 89 — (15 ) — 74 Cash, Cash Equivalents and Restricted Cash at Beginning of Period 22 — 292 — 314 Cash, Cash Equivalents and Restricted Cash at End of Period $ 111 $ — $ 277 $ — $ 388 LLC AND SUBSIDIARIES CONDENSED CONSOLIDATING STATEMENTS OF CASH FLOWS For the Nine Months Ended September 30, 2017 (Unaudited) Clearway Energy LLC (a) Other Guarantor Subsidiaries Non-Guarantor Subsidiaries (a) Clearway Energy Operating LLC (Note Issuer) (a) Consolidated (a) (In millions) Net Cash Provided by Operating Activities $ — $ 34 $ 417 $ (77 ) $ 374 Cash Flows from Investing Activities Intercompany transactions from Clearway Energy LLC to subsidiaries (13 ) — — 13 — Payments for the Drop Down Assets — — — (176 ) (176 ) Capital expenditures — — (102 ) — (102 ) Cash receipts from notes receivable — — 11 — 11 Return of investment from unconsolidated affiliates — 7 9 16 32 Net investments in unconsolidated affiliates — (41 ) (7 ) — (48 ) Net Cash Used in Investing Activities (13 ) (34 ) (89 ) (147 ) (283 ) Cash Flows from Financing Activities Transfer of funds under intercompany cash management arrangement (6 ) (1 ) — 7 — Net contributions from noncontrolling interests — — — 13 13 Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets — 25 (44 ) (7 ) (26 ) Proceeds from the issuance of Class C units 33 — — 33 (Payments of) proceeds from distributions (149 ) — (211 ) 211 (149 ) Payments of debt issuance costs — — (12 ) — (12 ) Proceeds from the issuance of long-term debt - external — — 130 — 130 Payments for long-term debt — external — (30 ) (225 ) — (255 ) Net Cash (Used in) Provided by Financing Activities (122 ) (6 ) (362 ) 224 (266 ) Net Decrease in Cash, Cash Equivalents and Restricted Cash (135 ) (6 ) (34 ) — (175 ) Cash, Cash Equivalents and Restricted Cash at Beginning of Period 211 9 277 — 497 Cash, Cash Equivalents and Restricted Cash at End of Period $ 76 $ 3 $ 243 $ — $ 322 (a) Retrospectively adjusted as discussed in Note 1, Nature of Business .

Nature of Business (Details)

Nature of Business (Details) $ in Millions

Sep. 27, 2018USD ($)shares

Mar. 31, 2018USD ($)

Aug. 02, 2017USD ($)

Mar. 27, 2017USD ($)MW

Sep. 30, 2018USD ($)MWshares

Sep. 30, 2017USD ($)

[3]

May 31, 2018USD ($)

Mar. 30, 2018USD ($)

Dec. 31, 2017USD ($)

Aug. 01, 2017

Nature of Business

Megawatts Thermal Equivalent, Available Under right-to-use Provisions

134

Power Generation Capacity, Megawatts

[1],[2]

5,405

Weighted Average Remaining PPA Term

15 years

Net proceeds from the issuance of Class C units | $

$ 151

$ 33

Power Generation Capacity, Megawatts, including portion attributable to noncontrolling interest

5,411

Long-term Debt | $

$ 5,856

$ 6,068

Sale of Stock, Number of Shares Issued in Transaction | shares

3,916,449

4,392,583

Proceeds from Issuance or Sale of Equity | $

$ 75

Conventional Generation, Utility-Scale Solar, Distributed Solar, and Wind [Member]

Nature of Business

Power Generation Capacity, Megawatts

5,272

Distributed Solar

Nature of Business

Power Generation Capacity, Megawatts

[1]

52

Wind Farms [Member]

Nature of Business

Power Generation Capacity, Megawatts

[1]

2,200

Thermal [Member]

Nature of Business

Percentage of Ownership

[4]

100.00%

Steam and Chilled Water Capacity, Megawatts Thermal Equivalent

[1],[4]

1,392

Power Generation Capacity, Megawatts

[1]

133

Conventional Generation [Member]

Nature of Business

Power Generation Capacity, Megawatts

[1]

1,945

Utility-Scale Solar

Nature of Business

Power Generation Capacity, Megawatts

[1]

1,075

Clearway Energy, Inc. [Member]

Nature of Business

Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Voting Interest

45.00%

Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest

55.70%

Spring Canyon [Member] | Wind Farms [Member]

Nature of Business

Power Generation Capacity, Megawatts attributed to noncontrolling interest

6

NRG Yield LLC

Nature of Business

Net proceeds from the issuance of Class C units | $

$ 151

$ 33

NRG Yield LLC | CEG [Member]

Nature of Business

Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Voting Interest

55.00%

Limited Liability Company or Limited Partnership, Members or Limited Partners, Ownership Interest

44.30%

GenConn Middletown | Conventional Generation [Member]

Nature of Business

Equity Method Investment, Ownership Percentage

50.00%

Power Generation Capacity, Megawatts

[1]

95

GenConn Devon [Member] | Conventional Generation [Member]

Nature of Business

Equity Method Investment, Ownership Percentage

50.00%

Power Generation Capacity, Megawatts

[1]

95

Marsh Landing | Conventional Generation [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

720

El Segundo [Member] | Conventional Generation [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

550

Walnut Creek [Member] | Conventional Generation [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

485

Agua Caliente [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

16.00%

Power Generation Capacity, Megawatts

[1]

46

Alpine [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

66

Avenal [Member] | Utility-Scale Solar

Nature of Business

Equity Method Investment, Ownership Percentage

50.00%

Power Generation Capacity, Megawatts

[1]

23

Avra Valley | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

26

Blythe [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

21

Borrego | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

26

CVSR [Member] | Utility-Scale Solar

Nature of Business

Equity Method Investment, Ownership Percentage

100.00%

Power Generation Capacity, Megawatts

[1]

250

Desert Sunlight [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

25.00%

Kansas South [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

20

Solar Roadrunner LLC [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

20

TA - High Desert LLC [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

20

Utah Portfolio [Member] | Utility-Scale Solar

Nature of Business

Percentage of Ownership

[5],[6]

50.00%

Power Generation Capacity, Megawatts

[1],[5],[6]

265

AZ DG Solar Projects | Distributed Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

5

SPP Projects [Member] | Distributed Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

25

Other DG Assets [Member] | Distributed Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

13

PFMG DG Solar Projects | Distributed Solar

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

9

Alta I [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

150

Alta II [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

150

Alta III [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

150

Alta IV [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

102

Alta V [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

168

Alta X [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5]

100.00%

Power Generation Capacity, Megawatts

[1],[5]

137

Alta XI [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5]

100.00%

Power Generation Capacity, Megawatts

[1],[5]

90

South Trent | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

101

Spanish Fork [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

19

Laredo Ridge [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

80

Taloga [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

130

Pinnacle [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

55

Buffalo Bear [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

19

Spring Canyon II [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5]

90.10%

Power Generation Capacity, Megawatts

[1],[5]

29

Spring Canyon III [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5]

90.10%

Power Generation Capacity, Megawatts

[1],[5]

25

Crosswinds [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

99.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

21

Elbow Creek [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

122

Elkhorn Ridge Wind, LLC [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

66.70%

Power Generation Capacity, Megawatts

[1],[5],[7]

54

Forward [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

29

Goat Wind [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

150

Hardin [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

99.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

15

Lookout [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

38

Odin Wind Farm [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

99.90%

Power Generation Capacity, Megawatts

[1],[5],[7]

20

San Juan Mesa Wind Project, LLC [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

75.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

90

Sleeping Bear [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

95

Wildorado [Member] | Wind Farms [Member]

Nature of Business

Percentage of Ownership

[5],[7]

100.00%

Power Generation Capacity, Megawatts

[1],[5],[7]

161

Thermal [Member] | Thermal [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

30

Buckthorn Solar [Member] | Utility-Scale Solar

Nature of Business

Equity Method Investment, Ownership Percentage

100.00%

Power Generation Capacity, Megawatts

154

Energy Center Dover [Member] | Thermal [Member]

Nature of Business

Percentage of Ownership

100.00%

Power Generation Capacity, Megawatts

[1]

103

Buckthorn Solar Drop Down Asset [Member]

Nature of Business

Power Generation Capacity, Megawatts

154

Acquisition of businesses, net of cash acquired | $

$ (42)

Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value | $

$ 19

August 2017 Drop Down Assets [Member]

Nature of Business

Acquisition of businesses, net of cash acquired | $

$ (44)

Business Combination, Contingent Consideration, Liability | $

$ (8)

Southern California Edison [Member] | Desert Sunlight [Member] | Utility-Scale Solar

Nature of Business

Power Generation Capacity, Megawatts

[1]

63

Pacific Gas and Electric [Member] | Desert Sunlight [Member] | Utility-Scale Solar

Nature of Business

Power Generation Capacity, Megawatts

[1]

75

Unconsolidated Properties [Member]

Nature of Business

Power Generation Capacity, Megawatts

268

August 2017 Drop Down Assets [Member]

Nature of Business

Business Acquisition, Percentage of Voting Interests Acquired

25.00%

March 2017 Drop Down Assets [Member]

Nature of Business

Acquisition of businesses, net of cash acquired | $

$ (128)

Business Acquisition, Consideration Transferred, Working Capital | $

$ 3

Agua Caliente Borrower 2 [Member]

Nature of Business

Percentage of NRG's Ownership

31.00%

Equity Method Investment, Ownership Percentage

16.00%

Power Generation Capacity, Megawatts

46

Buckthorn Solar, due 2025 [Member]

Nature of Business

Long-term Debt | $

$ 132

$ 132

$ 169

Buckthorn Solar, due 2025 [Member] | Buckthorn Solar Drop Down Asset [Member]

Nature of Business

Long-term Debt | $

$ 183

[1]

(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 September 30, 2018.

[2]

(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.

[3]

(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

[4]

(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.

[5]

(b) Projects are part of tax equity arrangements.

[6]

(e) Represents interests in Four Brothers Solar, LLC, Granite Mountain Holdings, LLC, and Iron Springs Holdings, LLC, all acquired as part of the March 2017 Drop Down Assets (ownership percentage is based upon cash to be distributed).

[7]

(f) Projects are part of Wind TE Holdco portfolio.

Summary of Significant Accoun_4

Summary of Significant Accounting Policies (Details) - USD ($) $ / shares in Units, $ in Millions		Sep. 27, 2018	May 31, 2018	Sep. 30, 2018	Sep. 30, 2018		Jun. 30, 2018	Mar. 31, 2018	Sep. 30, 2017		Sep. 30, 2018		Sep. 30, 2017		Dec. 31, 2017
Summary of Significant Accounting Policies [Line Items]
Accounts Receivable, Net				$ 141	$ 141						$ 141
Revenue from Contract with Customer, Excluding Assessed Tax					63						182
Capitalized Contract Cost, Amortization					17						52
Total operating revenues					292				$ 269	[1]	824		$ 778	[1]
Operating Leases, Income Statement, Contingent Revenue					246						694
Members' Equity Attributable to Noncontrolling Interest				(193)	(193)						(193)				$ (162)	[1]
Cash and cash equivalents				231	231						231				146	[1]
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment				1,507	1,507						1,507				1,285
Noncontrolling interest				$ 193	193						193				162	[1]
Capital contributions from tax equity investors, net of distributions (a)	[1]												13
Comprehensive loss					$ (2)				(23)	[1]	$ (95)		(56)	[1]
Dividends Payable, Date Declared											Oct. 31, 2018
Common Stock, Dividends, Per Share, Declared											$ 0.331
Dividends Payable, Date to be Paid											Dec. 17, 2018
Dividends Payable, Date of Record											Dec. 3, 2018
Common Stock, Par or Stated Value Per Share				$ 0.01	$ 0.01						$ 0.01
ATM Program, Maximum Dollar Value of Shares to Be Issued				$ 150	$ 150						$ 150
Proceeds from Issuance of Common Stock, Before Commission Fees											77
Dividends Per Class A Common Share					$ 0.320		$ 0.309	$ 0.298
Intangible assets, accumulated amortization				289	$ 289						289				237
Restricted cash				157	157						$ 157				$ 168	[1]
Sale of Stock, Number of Shares Issued in Transaction		3,916,449									4,392,583
Net proceeds from the issuance of Class C units											$ 151		33	[1]
ATM program, dollar value of shares remaining				38	38						38
Financial Institutions [Member]
Summary of Significant Accounting Policies [Line Items]
Capital contributions from tax equity investors, net of distributions (a)	[2]										108
CEG [Member]
Summary of Significant Accounting Policies [Line Items]
Capital contributions from tax equity investors, net of distributions (a)	[2]										18
Buckthorn Solar Drop Down Asset [Member]
Summary of Significant Accounting Policies [Line Items]
Capital contributions from tax equity investors, net of distributions (a)			$ 80								99
Conventional Generation [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					0						0
Capitalized Contract Cost, Amortization					1						4
Total operating revenues					87				88		251		246
Operating Leases, Income Statement, Contingent Revenue					88						255
Renewables
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					9						35
Capitalized Contract Cost, Amortization					15						46
Total operating revenues					152				135		427		402
Operating Leases, Income Statement, Contingent Revenue					158						438
Thermal [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					54						147
Capitalized Contract Cost, Amortization					1						2
Total operating revenues					53				$ 46		146		$ 130
Operating Leases, Income Statement, Contingent Revenue					0						1
Energy Revenue [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					219	[3]					617	[4]
Operating Leases, Income Statement, Contingent Revenue					160						444
Energy Revenue [Member] | Conventional Generation [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					2	[3]					5	[4]
Operating Leases, Income Statement, Contingent Revenue					2						5
Energy Revenue [Member] | Renewables
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					167	[3]					473	[4]
Operating Leases, Income Statement, Contingent Revenue					158						438
Energy Revenue [Member] | Thermal [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					50	[3]					139	[4]
Operating Leases, Income Statement, Contingent Revenue											1
Capacity Revenue [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					90	[3]					259	[4]
Operating Leases, Income Statement, Contingent Revenue					86						250
Capacity Revenue [Member] | Conventional Generation [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					86	[3]					250	[4]
Operating Leases, Income Statement, Contingent Revenue					86						250
Capacity Revenue [Member] | Renewables
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					0	[3]					0	[4]
Operating Leases, Income Statement, Contingent Revenue					0						0
Capacity Revenue [Member] | Thermal [Member]
Summary of Significant Accounting Policies [Line Items]
Revenue from Contract with Customer, Excluding Assessed Tax					4	[3]					9	[4]
Operating Leases, Income Statement, Contingent Revenue											0
Lease Agreements [Member]
Summary of Significant Accounting Policies [Line Items]
Accounts Receivable, Net				106	106						106
Customer Contracts [Member]
Summary of Significant Accounting Policies [Line Items]
Accounts Receivable, Net				35	$ 35						$ 35
CEG [Member]
Summary of Significant Accounting Policies [Line Items]
Payment of capital distributions and returns of capital, net of capital distributions, non-cash				$ 17
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	Activity primarily relates to net capital contributions from the TE investor into Buckthorn Holdings LLC in the amount of $99 million, as further described in Note 4, Investments Accounted for by the Equity Method and Variable Interest Entities.
[3]	(a) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables TotalEnergy Revenue $2 $158 $160Capacity Revenue 86 — 86 88 158 246
[4]	(b) The following amounts of energy and capacity revenue relate to leases and are accounted for under ASC 840: Conventional Generation Renewables Thermal TotalEnergy Revenue $5 $438 $1 $444Capacity Revenue 250 — — 250 255 438 1 694

Business Acquisitions Thermal (

Business Acquisitions Thermal (Details) $ in Millions		Apr. 18, 2018USD ($)MW	Mar. 31, 2018USD ($)	Sep. 30, 2018MW	Jun. 19, 2018USD ($)
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1],[2]			5,405
Central CA Fuel Cell 1 [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred | $		$ 11
Power Generation Capacity, Megawatts		2.8
Power Purchase Agreement Period		20 years
UPMC Thermal [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred | $			$ 84
Accounts Payable, Related Parties | $					$ 5
Thermal [Member]
Business Acquisition [Line Items]
Steam and Chilled Water Capacity, Megawatts Thermal Equivalent	[1],[3]			1,392
Power Generation Capacity, Megawatts	[1]			133
Thermal [Member] | UPMC Thermal [Member]
Business Acquisition [Line Items]
Steam and Chilled Water Capacity, Megawatts Thermal Equivalent				73
Power Generation Capacity, Megawatts				7.5
[1]	(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 September 30, 2018.
[2]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.
[3]	(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 Acquisitions Busines_3

Business Acquisitions Business Acquisitions - Buckthorn Solar Drop Down Asset (Details) $ in Millions		May 31, 2018USD ($)	Mar. 31, 2018USD ($)	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Mar. 30, 2018USD ($)	Dec. 31, 2017USD ($)
Business Acquisition [Line Items]
Total operating revenues				$ 292	$ 269	[1]	$ 824	$ 778	[1]
Long-term Debt				$ 5,856			$ 5,856				$ 6,068
Power Generation Capacity, Megawatts | MW	[2],[3]			5,405			5,405
Assets, Current				$ 602			$ 602				481	[1]
Net property, plant and equipment				5,306			5,306				5,410	[1]
Other Assets				2,483			2,483				2,469	[1]
Assets				8,391			8,391				8,360	[1]
Liabilities				6,118			6,118				6,331	[1]
Members' Equity				2,273			2,273				2,029	[1]
Operating Income (Loss)				100	84	[1]	293	263	[1]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest				64	42	[1]	172	98	[1]
Net Income (Loss) Attributable to Noncontrolling Interest				(2)	(23)	[1]	(95)	(56)	[1]
Net Income (Loss) Attributable to Parent				66	65	[1]	267	154	[1]
Net contributions from noncontrolling interests	[1]							13
Buckthorn Solar Drop Down Asset [Member]
Business Acquisition [Line Items]
Total operating revenues					0			0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets				20			20
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment				212			212
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net				$ 25			$ 25
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value										$ 19
Power Generation Capacity, Megawatts | MW				154			154
Business Combination, Consideration Transferred			$ 42
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets				$ 3			$ 3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets				235			235
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities	[4]			176			176
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other				15			15
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities				191			191
Operating Income (Loss)					0			0
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest					1			(2)
Net Income (Loss) Attributable to Noncontrolling Interest					0			0
Net Income (Loss) Attributable to Parent					1
Buckthorn Solar, due 2025 [Member]
Business Acquisition [Line Items]
Long-term Debt		$ 132		132			132				$ 169
Buckthorn Solar, due 2025 [Member] | Buckthorn Solar Drop Down Asset [Member]
Business Acquisition [Line Items]
Long-term Debt										$ 183
Previously Reported [Member]
Business Acquisition [Line Items]
Total operating revenues	[5]				265			767
Operating Income (Loss)	[5]				95			271
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest	[5]							110
Net Income (Loss) Attributable to Noncontrolling Interest	[5]				(23)			(56)
Net Income (Loss) Attributable to Parent	[5]				$ 75			$ 166
Buckthorn Solar Drop Down Asset [Member]
Business Acquisition [Line Items]
Net property, plant and equipment				225			225
Other Assets				21			21
Assets				246			246
Liabilities				$ 136			136
Net Income (Loss) Attributable to Noncontrolling Interest							(55)
Net contributions from noncontrolling interests		$ 80					$ 99
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(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 September 30, 2018.
[3]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.
[4]	(a) Net of $7 million of net debt issuance costs.
[5]	As previously reported in the Company's Form 10-Q for the quarter ended September 30, 2017.

Business Acquisitions Busines_4

Business Acquisitions Business Acquisitions - November 2017 Drop Down (Details) $ in Millions		Mar. 31, 2018USD ($)	Nov. 02, 2017USD ($)	Mar. 27, 2017USD ($)	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Dec. 31, 2017USD ($)	Nov. 01, 2017USD ($)MW
Business Acquisition [Line Items]
Total operating revenues					$ 292	$ 269	[1]	$ 824	$ 778	[1]
Debt Issuance Costs, Net					$ 56			$ 56			$ 62
Power Generation Capacity, Megawatts | MW	[2],[3]				5,405			5,405
Long-term Debt					$ 5,856			$ 5,856			$ 6,068
Operating Income (Loss)					100	84	[1]	293	263	[1]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest					64	42	[1]	172	98	[1]
Net Income (Loss) Attributable to Noncontrolling Interest					(2)	(23)	[1]	(95)	(56)	[1]
Net Income (Loss) Attributable to Parent					$ 66	65	[1]	$ 267	154	[1]
November 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Total operating revenues						4			11
Power Generation Capacity, Megawatts | MW												38
Business Combination, Consideration Transferred			$ 74
Operating Income (Loss)									(8)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									(10)
Net Income (Loss) Attributable to Noncontrolling Interest						0			0
Buckthorn Solar Drop Down Asset [Member]
Business Acquisition [Line Items]
Total operating revenues						0			0
Power Generation Capacity, Megawatts | MW					154			154
Business Combination, Consideration Transferred		$ 42
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets					$ 20			$ 20
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment					212			212
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Noncurrent Assets					3			3
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets					235			235
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Financial Liabilities	[4]				176			176
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Other					15			15
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities					191			191
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net					$ 25			$ 25
Operating Income (Loss)						0			0
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest						1			(2)
Net Income (Loss) Attributable to Noncontrolling Interest						0			0
Net Income (Loss) Attributable to Parent						1
November 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Long-term Debt												$ 26
March 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred				$ 128
Net Income (Loss) Attributable to Parent						$ (11)			$ (10)
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(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 September 30, 2018.
[3]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.
[4]	(a) Net of $7 million of net debt issuance costs.

Business Acquisitions Busines_5

Business Acquisitions Business Combination August 2017 Drop Down (Details) - USD ($) $ in Millions	Mar. 31, 2018	Nov. 02, 2017	Aug. 02, 2017	Mar. 27, 2017	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017		Aug. 01, 2017
Business Acquisition [Line Items]
Total operating revenues					$ 292	$ 269	[1]	$ 824	$ 778	[1]
Operating Income (Loss)					100	84	[1]	293	263	[1]
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest					64	42	[1]	172	98	[1]
Net Income (Loss) Attributable to Noncontrolling Interest					(2)	(23)	[1]	(95)	(56)	[1]
Net Income (Loss) Attributable to Parent					66	65	[1]	267	154	[1]
Buckthorn Solar Drop Down Asset [Member]
Business Acquisition [Line Items]
Total operating revenues						0			0
Business Combination, Consideration Transferred	$ 42
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net					25			25
Operating Income (Loss)						0			0
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest						1			(2)
Net Income (Loss) Attributable to Noncontrolling Interest						0			0
Net Income (Loss) Attributable to Parent						1
August 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred			$ 44
Business Combination, Contingent Consideration, Liability					8			8
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net											$ 87
November 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Total operating revenues						4			11
Business Combination, Consideration Transferred		$ 74
Operating Income (Loss)									(8)
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest									(10)
Net Income (Loss) Attributable to Noncontrolling Interest						0			0
March 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred				$ 128
Business Acquisition, Consideration Transferred, Working Capital					$ 3			$ 3
Net Income (Loss) Attributable to Parent						$ (11)			$ (10)
August 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired											25.00%
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Business Acquisitions Busines_6

Business Acquisitions Business Acquisitions - March 2017 Drop Down (Details) $ in Millions		Mar. 27, 2017USD ($)MW	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Dec. 31, 2017USD ($)
Business Acquisition [Line Items]
Total operating revenues			$ 292	$ 269	[1]	$ 824	$ 778	[1]
Power Generation Capacity, Megawatts | MW	[2],[3]		5,405			5,405
Equity investments in affiliates			$ 1,182			$ 1,182			$ 1,178	[1]
Debt Issuance Costs, Net			56			56			$ 62
Operating Income (Loss)			100	84	[1]	293	263	[1]
Net Income			64	42	[1]	172	98	[1]
Net Income (Loss) Attributable to Parent			$ 66	65	[1]	$ 267	154	[1]
Agua Caliente Borrower 2 [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage			16.00%			16.00%
Percentage of NRG's Ownership		31.00%
Power Generation Capacity, Megawatts | MW		46
Power Purchase Agreement Period		25 years
Remaining Power Purchase Agreement term		22 years
Non-Recourse Debt		$ 41
Utah Portfolio [Member]
Business Acquisition [Line Items]
Remaining Power Purchase Agreement term		20 years
Percentage of Cash Available for Distributions			50.00%			50.00%
Non-Recourse Debt		$ 287
March 2017 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred		128
Business Acquisition, Consideration Transferred, Working Capital			$ 3			$ 3
Business Combination, Separately Recognized Transactions, Net Gains and Losses		$ 8
Net Income (Loss) Attributable to Parent				$ (11)			$ (10)
NRG [Member] | Agua Caliente Borrower 2 [Member]
Business Acquisition [Line Items]
Percentage of Ownership		51.00%
NRG [Member] | Utah Portfolio [Member]
Business Acquisition [Line Items]
Percentage of Cash Available for Distributions			50.00%			50.00%
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(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 September 30, 2018.
[3]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.

Variable Interest Entities Vari

Variable Interest Entities Variable Interest Entities - Consolidated Entities (Details) $ in Millions		May 31, 2018USD ($)	Mar. 31, 2018USD ($)	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Mar. 30, 2018USD ($)	Dec. 31, 2017USD ($)
Schedule of Equity Method Investments [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest				$ (2)	$ (23)	[1]	$ (95)	$ (56)	[1]
Power Generation Capacity, Megawatts | MW	[2],[3]			5,405			5,405
Other Assets				$ 2,483			$ 2,483				$ 2,469	[1]
Net property, plant and equipment				5,306			5,306				5,410	[1]
Total Assets				8,391			8,391				8,360	[1]
Total Liabilities				6,118			6,118				6,331	[1]
Long-term Debt				5,856			5,856				6,068
Net contributions from noncontrolling interests	[1]							13
November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Other Assets				192			192
Net property, plant and equipment				354			354
Intangible Assets, Net (Excluding Goodwill)				2			2
Total Assets				548			548
Total Liabilities				205			205
Noncontrolling Interest in Variable Interest Entity				32			32
Net Assets				311			311
Alta X and XI TE Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Other Assets				32			32
Net property, plant and equipment				417			417
Intangible Assets, Net (Excluding Goodwill)				253			253
Total Assets				702			702
Total Liabilities				14			14
Noncontrolling Interest in Variable Interest Entity				67			67
Net Assets				621			621
Spring Canyon [Member]
Schedule of Equity Method Investments [Line Items]
Other Assets				1			1
Net property, plant and equipment				92			92
Intangible Assets, Net (Excluding Goodwill)				0			0
Total Assets				93			93
Total Liabilities				5			5
Noncontrolling Interest in Variable Interest Entity				50			50
Net Assets				38			38
Buckthorn Solar Drop Down Asset [Member]
Schedule of Equity Method Investments [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest							(55)
Other Assets				21			21
Net property, plant and equipment				225			225
Intangible Assets, Net (Excluding Goodwill)				0			0
Total Assets				246			246
Total Liabilities				136			136
Noncontrolling Interest in Variable Interest Entity				44			44
Net Assets				$ 66			66
Net contributions from noncontrolling interests		$ 80					$ 99
Buckthorn Solar Drop Down Asset [Member]
Schedule of Equity Method Investments [Line Items]
Net Income (Loss) Attributable to Noncontrolling Interest					$ 0			$ 0
Power Generation Capacity, Megawatts | MW				154			154
Business Combination, Consideration Transferred			$ 42
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value										$ 19
Buckthorn Solar, due 2025 [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt		$ 132		$ 132			$ 132				$ 169
Buckthorn Solar, due 2025 [Member] | Buckthorn Solar Drop Down Asset [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt										$ 183
CEG [Member] | Repowering Partnership LLC [Member]
Schedule of Equity Method Investments [Line Items]
Payments for Deposits							$ 17
Noncontrolling Interest, Ownership Percentage by Noncontrolling Owners				21.00%			21.00%
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(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 September 30, 2018.
[3]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.

Variable Interest Entities Va_2

Variable Interest Entities Variable Interest Entities - Unconsolidated Entities (Details) $ in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)	[1]	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)	[1]	Dec. 31, 2017USD ($)	[1]
Schedule of Equity Method Investments [Line Items]
Operating revenues		$ 292	$ 269		$ 824	$ 778
Equity investments in affiliates		1,182			1,182			$ 1,178
Operating Income (Loss)		100	84		293	263
Net Income (Loss)		64	$ 42		172	$ 98
Total current assets		602			602			481
Current Liabilities		1,080			1,080			539
Total non-current liabilities		$ 5,038			$ 5,038			$ 5,792
Power Generation Capacity, Megawatts | MW	[2],[3]	5,405			5,405
DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Interest in Subsidiaries and Affiliates					$ 4
Equity investments in affiliates		$ 78			78
Due to Affiliate		$ 1			$ 1
Power Generation Capacity, Megawatts | MW		52			52
Remaining Lease Term					17 years
DGPV Holdco 3 [Member]
Schedule of Equity Method Investments [Line Items]
Payments to Acquire Interest in Subsidiaries and Affiliates					$ 12
Equity investments in affiliates		$ 85			85
Due to Affiliate		$ 10			$ 10
Power Generation Capacity, Megawatts | MW		59			59
Remaining Lease Term					21 years
Four Brothers Solar [Member]
Schedule of Equity Method Investments [Line Items]
Equity investments in affiliates		$ 204			$ 204
Granite Mountain Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Equity investments in affiliates		74			74
Iron Springs Holdings [Member]
Schedule of Equity Method Investments [Line Items]
Equity investments in affiliates		52			52
NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Equity investments in affiliates		63			63
Gen Conn Energy LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity investments in affiliates		98			98
RPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Equity investments in affiliates		$ 42			$ 42
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(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 September 30, 2018.
[3]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.

Variable Interest Entities Va_3

Variable Interest Entities Variable Interest Entities - Utah Solar Portfolio (Details) - Utah Portfolio [Member]	Sep. 30, 2018
Variable Interest Entity [Line Items]
Percentage of Cash Available for Distributions	50.00%
Capital Unit, Class A [Member]
Variable Interest Entity [Line Items]
Percentage of Ownership	100.00%
Financial Institutions [Member] | Capital Unit, Class B [Member]
Variable Interest Entity [Line Items]
Taxable Income Allocation, Pre-Flip	99.00%
Taxable Income Allocation, Post-Flip	50.00%

Fair Value of Financial Instr_3

Fair Value of Financial Instruments Fair Value of Financial Instruments - Balance Sheet Grouping (Details) - USD ($) $ in Millions		Sep. 30, 2018	Dec. 31, 2017
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term debt — affiliate		$ 44	$ 618	[1]
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financing Receivable, Net		3	13
Long-term debt — affiliate		603
Long-term Debt and Capital Lease Obligations, Including Current Maturities	[2]	5,253	5,450	[1]
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financing Receivable, Net		3	13
Long-term debt — affiliate		603	618
Long-term Debt and Capital Lease Obligations, Including Current Maturities	[2]	5,218	5,466
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities		834	870
Estimate of Fair Value Measurement [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities		$ 4,987	$ 5,214
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) Excludes deferred financing costs, which are recorded as a reduction to long-term debt on the Company's consolidated balance sheets.

Fair Value of Financial Instr_4

Fair Value of Financial Instruments Fair Value of Financial Instruments - Recurring Fair Value (Details) - USD ($)		Sep. 30, 2018		Dec. 31, 2017
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	$ 35,000,000		$ 2,000,000
Derivative Liability, Fair Value, Gross Liability		14,000,000		49,000,000
Fair Value Assets, Measured on Recurring Basis, Valuation Techniques, Impact of Credit Reserve to Fair Value		0
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset	[2]	35,000,000		2,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liability, Fair Value, Gross Liability	[2]	14,000,000		49,000,000
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net		0		0
Interest Rate Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset		35,000,000		1,000,000
Derivative Liability, Fair Value, Gross Liability		13,000,000		48,000,000
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset		35,000,000		1,000,000
Derivative Liability, Fair Value, Gross Liability		13,000,000		48,000,000
Commodity Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset				1,000,000
Derivative Liability, Fair Value, Gross Liability		1,000,000	[3]	1,000,000
Commodity Contract [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset, Fair Value, Gross Asset		0		1,000,000
Derivative Liability, Fair Value, Gross Liability		$ 1,000,000		$ 1,000,000
[1]	(a) Derivative Assets balances classified as current are included within the prepayments and other current assets line item of the consolidated balance sheets as of September 30, 2018 and December 31, 2017.
[2]	(a) There were no derivative assets or liabilities classified as Level 1 or Level 3 as of September 30, 2018 and December 31, 2017
[3]	(a) There were no commodity contracts classified as derivative assets as of September 30, 2018.

Fair Value of Financial Instr_5

Fair Value of Financial Instruments Fair Value of Financial Instruments - Credit Risk and Derivative FV Measurements (Details) $ in Millions	9 Months Ended
	Sep. 30, 2018USD ($)
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value Assets, Measured on Recurring Basis, Valuation Techniques, Impact of Credit Reserve to Fair Value	$ 0
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	$ 2,500
Estimated Counterparty Credit Risk Exposure to Certain Counterparties, Period	5 years

Accounting for Derivative Ins_3

Accounting for Derivative Instruments and Hedging Activities Accounting for Derivative Instruments and Hedging Activities - FV of Derivatives (Details) - USD ($) $ in Millions		3 Months Ended			9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017	Sep. 30, 2018		Sep. 30, 2017	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	$ 35			$ 35			$ 2
Derivative Liability, Fair Value, Gross Liability		14			14			49
Derivative, Collateral, Right to Reclaim Cash		0			0			0
Derivative, Collateral, Obligation to Return Cash		0			0			0
Fair Value of Gross Derivative Assets/(Liabilities), Net		21			21			(47)
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		21			21			(47)
Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	13			13			1
Derivative Liability, Fair Value, Gross Liability		5			5			13
Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	22			22			1
Derivative Liability, Fair Value, Gross Liability		9			9			36
Commodity Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset								1
Derivative Liability, Fair Value, Gross Liability		1	[2]		1	[2]		1
Derivative Asset, Fair Value, Gross Liability								0
Derivative Asset								1
Derivative Liability, Fair Value, Gross Asset		0	[2]		0	[2]		0
Derivative Liability		1	[2]		1	[2]		1
Fair Value of Gross Derivative Assets/(Liabilities), Net		(1)	[2]		(1)	[2]		0
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset		0	[2]		0	[2]		0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral		(1)	[2]		(1)	[2]		0
Interest Rate Contract Current [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	2			2			0
Derivative Liability, Fair Value, Gross Liability		1			1			4
Interest Rate Contract Current [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	1			1			0
Derivative Liability, Fair Value, Gross Liability		3			3			13
Interest Rate Contract Non Current [Member] | Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	11			11			1
Derivative Liability, Fair Value, Gross Liability		4			4			9
Interest Rate Contract Non Current [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]	21			21			0
Derivative Liability, Fair Value, Gross Liability		5			5			22
Commodity Contract Current [Member] | Not Designated as Hedging Instrument [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset	[1]							1
Derivative Liability, Fair Value, Gross Liability		1			1			1
Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Fair Value, Gross Asset		35			35			1
Derivative Liability, Fair Value, Gross Liability		13			13			48
Derivative Asset, Fair Value, Gross Liability		2			2			1
Derivative Asset		33			33			0
Derivative Liability, Fair Value, Gross Asset		2			2			1
Derivative Liability		11			11			47
Fair Value of Gross Derivative Assets/(Liabilities), Net		22			22			(47)
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		22			22			(47)
United States of America, Dollars | Interest [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		1,909			1,909			2,050
MMbtu [Member] | Natural Gas [Member]
Derivatives, Fair Value [Line Items]
Derivative, Notional Amount		2			2			$ 2
Interest Expense [Member] | Interest Rate Contract [Member]
Derivatives, Fair Value [Line Items]
Unrealized Gain (Loss) on Derivatives		$ 9		$ 7	$ 40		$ 2
[1]	(a) Derivative Assets balances classified as current are included within the prepayments and other current assets line item of the consolidated balance sheets as of September 30, 2018 and December 31, 2017.
[2]	(a) There were no commodity contracts classified as derivative assets as of September 30, 2018.

Accounting for Derivative Ins_4

Accounting for Derivative Instruments and Hedging Activities Accounting for Derivative Instruments and Hedging Activities - AOCI (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Derivative [Line Items]
Accumulated Other Comprehensive Loss	$ (35)	$ (79)	$ (35)	$ (79)	$ (42)	$ (69)	$ (86)	$ (86)
Reclassified from accumulated OCL to income due to realization of previously deferred amounts	5	5	13	13
Mark-to-market of cash flow hedge accounting contracts	2	2	21	(6)
Losses expected to be realized from OCL during the next 12 months			(9)
Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net				0
Noncontrolling Interest [Member]
Derivative [Line Items]
Accumulated Other Comprehensive Loss	(1)	(1)	(1)	(1)
Successor [Member]
Derivative [Line Items]
Accumulated Other Comprehensive Loss	$ (34)	$ (78)	$ (34)	$ (78)

Accounting for Derivative Ins_5

Accounting for Derivative Instruments and Hedging Activities Accounting for Derivative Instruments and Hedging Activities - Impact on Statement of Operations (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized Gain (Loss) on Derivatives	$ 9	$ 7	$ 40	$ 2

Long-term Debt Long-term Debt -

Long-term Debt Long-term Debt - Debt Table (Details) - USD ($) $ in Millions		Jun. 19, 2018	Apr. 30, 2018	Aug. 31, 2018	Sep. 30, 2018	Dec. 31, 2017		May 31, 2018
Debt Instrument [Line Items]
Long-term debt — affiliate					$ 44	$ 618	[1]
Long-term Debt					5,856	6,068
Current portion of long-term debt — external					(309)	(339)	[1]
Deferred Finance Costs, Net					(56)	(62)
Long-term Debt, Excluding Current Maturities					4,932	5,667
Energy Center Minneapolis Series C Notes [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 0	83
Debt Instrument, Interest Rate, Stated Percentage	[2]				5.95%
Repayments of Debt		$ 83
Intercompany Credit Agreement due 2019 [Member]
Debt Instrument [Line Items]
Long-term debt — affiliate					$ 322	337
Debt Instrument, Interest Rate, Stated Percentage	[2]				3.58%
Repayments of Debt				$ 16
Intercompany Credit Agreement due 2020 [Member]
Debt Instrument [Line Items]
Long-term debt — affiliate					$ 281	281
Debt Instrument, Interest Rate, Stated Percentage	[2]				3.325%
5.375% Senior Notes due in 2024 [Member]
Debt Instrument [Line Items]
Senior Notes					$ 500	500
Debt Instrument, Interest Rate, Stated Percentage	[2]				5.375%
5.00% Senior Notes due in 2026 [Member]
Debt Instrument [Line Items]
Senior Notes					$ 350	350
Debt Instrument, Interest Rate, Stated Percentage	[2]				5.00%
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt	[3]				$ 0	$ 55
Debt Instrument, Description of Variable Rate Basis					3 month LIBOR
Debt Instrument, Basis Spread on Variable Rate			1.75%		1.50%	2.50%
Agua Caliente Borrower 2 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 39	$ 41
Debt Instrument, Interest Rate, Stated Percentage	[2]				5.43%
Alpine Financing Agreement, due 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 129	135
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					1.75%
Alta Wind I-V, lease financing arrangement, due 2034 and 2035 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 901	926
Buckthorn Solar, due 2025 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 132	169		$ 132
Debt Instrument, Description of Variable Rate Basis					1-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					1.75%
CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 720	746
CVSR Holdco due 2037 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 188	194
Debt Instrument, Interest Rate, Stated Percentage	[2]				4.68%
Energy Center Minneapolis Series E, F, G, H Notes [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 203	0
Letters of Credit Outstanding, Amount					0
Proceeds from Issuance of Debt		203
Proceeds from (Repayments of) Debt		$ 120
Laredo Ridge Wind, LLC, due in 2026 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 91	95
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					1.875%
Marsh Landing Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 280	318
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					2.125%
Tapestry Wind LLC due in 2021 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 154	162
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					1.625%
Utah Solar Portfolio, due 2022 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 273	278
Viento Funding II, Inc., due in 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 154	163
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					3.00%
Walnut Creek Energy, LLC, due in 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 235	267
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate					1.625%
Other Debt [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 427	443
Letters of Credit Outstanding, Amount					36
Project [Domain]
Debt Instrument [Line Items]
Long-term Debt					$ 4,403	4,545
Buckthorn Solar Drop Down Asset [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate	[2]				1.75%
Energy Center Minneapolis Series D Notes [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 125	125
Debt Instrument, Interest Rate, Stated Percentage	[2]				3.55%
El Segundo Energy Center, due 2023 [Member]
Debt Instrument [Line Items]
Long-term Debt					$ 352	$ 400
Debt Instrument, Description of Variable Rate Basis					3-Month LIBOR
El Segundo Energy Center, due 2023 Tranche B [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					2.375%
El Segundo Energy Center, due 2023 Tranche A [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate					1.75%
Letter of Credit [Member] | Energy Center Minneapolis Series C Notes [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					$ 0
Letter of Credit [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					70
Letter of Credit [Member] | Agua Caliente Borrower 2 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					17
Letter of Credit [Member] | Alpine Financing Agreement, due 2022 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					16
Letter of Credit [Member] | Alta Wind I-V, lease financing arrangement, due 2034 and 2035 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					103
Letter of Credit [Member] | Buckthorn Solar, due 2025 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					26
Letter of Credit [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					0
Letter of Credit [Member] | CVSR Holdco due 2037 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					13
Letter of Credit [Member] | Laredo Ridge Wind, LLC, due in 2026 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					10
Letter of Credit [Member] | Marsh Landing Term Loan Facility [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					38
Letter of Credit [Member] | Tapestry Wind LLC due in 2021 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					20
Letter of Credit [Member] | Utah Solar Portfolio, due 2022 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					13
Letter of Credit [Member] | Viento Funding II, Inc., due in 2023 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					26
Letter of Credit [Member] | Walnut Creek Energy, LLC, due in 2023 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					82
Letter of Credit [Member] | Energy Center Minneapolis Series D Notes [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					0
Letter of Credit [Member] | El Segundo Energy Center, due 2023 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount					138
External and Affiliate Debt [Member]
Debt Instrument [Line Items]
Current portion of long-term debt — external	[4]				$ (868)
Minimum [Member] | Alta Wind I-V, lease financing arrangement, due 2034 and 2035 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					5.696%
Minimum [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					2.339%
Maximum [Member] | Alta Wind I-V, lease financing arrangement, due 2034 and 2035 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					7.015%
Maximum [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage					3.775%
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) As of September 30, 2018, L+ equals 3 month LIBOR plus x%, except for Viento, due 2023 where L+ equals 6 month LIBOR plus 3.00% and Utah Solar Portfolio, where L+ equals 1 month LIBOR plus x%.
[3]	(b) Applicable rate is determined by the borrower leverage ratio, as defined in the credit agreement.
[4]	Current maturities reflect the results of the 2019 Convertible Notes and 2020 Convertible Notes tender offer, as further described below.

Long-term Debt Long-term Debt_2

Long-term Debt Long-term Debt - Debt Disclosures (Details) - USD ($) $ in Millions

Oct. 10, 2018

Oct. 02, 2018

Aug. 31, 2018

Jun. 19, 2018

Apr. 30, 2018

Aug. 31, 2018

Sep. 30, 2018

Dec. 31, 2017

Oct. 09, 2018

Oct. 01, 2018

May 31, 2018

Mar. 30, 2018

Debt Instrument [Line Items]

Long-term Debt

$ 5,856

$ 6,068

Due to Affiliate, Noncurrent

$ 44

618

[1]

Energy Center Minneapolis Series E Notes [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

4.80%

Proceeds from Issuance of Debt

$ 70

Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Line of Credit Facility, Fair Value of Amount Outstanding

$ 0

Long-term Debt

[2]

$ 0

$ 55

Debt Instrument, Basis Spread on Variable Rate

1.75%

1.50%

2.50%

Buckthorn Solar, due 2025 [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 132

$ 169

$ 132

Debt Instrument, Basis Spread on Variable Rate

1.75%

Utah Solar Portfolio, due 2022 [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 273

278

Agua Caliente Borrower 2 [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

[3]

5.43%

Long-term Debt

$ 39

41

Buckthorn Solar Drop Down Asset [Member]

Debt Instrument [Line Items]

Debt Instrument, Basis Spread on Variable Rate

[3]

1.75%

Thermal [Member]

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

$ 40

3.5% Convertible Notes due 2019 [Member]

Debt Instrument [Line Items]

Repayments of Debt

$ 16

Intercompany Credit Agreement due 2019 [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

[3]

3.58%

Repayments of Debt

16

Due to Affiliate, Noncurrent

$ 322

337

Intercompany Credit Agreement due 2020 [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

[3]

3.325%

Due to Affiliate, Noncurrent

$ 281

281

Energy Center Minneapolis Series F Notes [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

4.60%

Proceeds from Issuance of Debt

10

Energy Center Minneapolis Series G Notes [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

5.90%

Proceeds from Issuance of Debt

83

Energy Center Minneapolis Series H Notes [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

4.83%

Proceeds from Issuance of Debt

40

Energy Center Minneapolis Series E, F, G, H Notes [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

$ 0

Long-term Debt

$ 203

0

Proceeds from Issuance of Debt

203

Proceeds from (Repayments of) Debt

120

Energy Center Minneapolis Series C Notes [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

[3]

5.95%

Long-term Debt

$ 0

$ 83

Repayments of Debt

$ 83

Letter of Credit [Member] | Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

70

Letter of Credit [Member] | Buckthorn Solar, due 2025 [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

26

Letter of Credit [Member] | Utah Solar Portfolio, due 2022 [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

13

Letter of Credit [Member] | Agua Caliente Borrower 2 [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

17

Letter of Credit [Member] | Energy Center Minneapolis Series C Notes [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

$ 0

Bridge Loan [Member]

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

$ 1,500

$ 1,500

Debt Instrument, Basis Spread on Libor Rate

3.00%

3.00%

Debt Instrument, Basis Spread on Variable Rate

2.00%

Buckthorn Solar Drop Down Asset [Member] | Buckthorn Solar, due 2025 [Member]

Debt Instrument [Line Items]

Long-term Debt

$ 183

Buckthorn Solar Drop Down Asset [Member] | Buckthorn Solar Drop Down Asset [Member]

Debt Instrument [Line Items]

Derivative, Nonmonetary Notional Amount, Percent of Required Need, Coverage

80.00%

Subsequent Event [Member] | 5.75% Senior Notes due 2025 [Member]

Debt Instrument [Line Items]

Debt Instrument, Interest Rate, Stated Percentage

5.75%

Proceeds from Issuance of Debt

$ 600

Subsequent Event [Member] | 3.5% Convertible Notes due 2019 [Member]

Debt Instrument [Line Items]

Repayments of Debt

$ 109

Subsequent Event [Member] | Intercompany Credit Agreement due 2019 [Member]

Debt Instrument [Line Items]

Due to Affiliate, Noncurrent

$ 216

Subsequent Event [Member] | 3.25% Convertible Notes due 2020 [Member]

Debt Instrument [Line Items]

Repayments of Debt

$ 243

Subsequent Event [Member] | Intercompany Credit Agreement due 2020 [Member]

Debt Instrument [Line Items]

Due to Affiliate, Noncurrent

44

Subsequent Event [Member] | Letter of Credit [Member] | Revolving Credit Facility [Member]

Debt Instrument [Line Items]

Letters of Credit Outstanding, Amount

$ 45

Subsequent Event [Member] | Bridge Loan [Member]

Debt Instrument [Line Items]

Line of Credit Facility, Maximum Borrowing Capacity

$ 867.5

[1]

(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

[2]

(b) Applicable rate is determined by the borrower leverage ratio, as defined in the credit agreement.

[3]

(a) As of September 30, 2018, L+ equals 3 month LIBOR plus x%, except for Viento, due 2023 where L+ equals 6 month LIBOR plus 3.00% and Utah Solar Portfolio, where L+ equals 1 month LIBOR plus x%.

Segment Reporting (Details)

Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017		Dec. 31, 2017	[1]
Segment Reporting
Operating revenues	$ 292	$ 269	[1]	$ 824	$ 778	[1]
Cost of operations	84	79		247	241
Depreciation and amortization	84	90	[1]	247	246	[1]
Asset Impairment Charges	0	12		0	12
General and administrative	6	4	[1]	17	14	[1]
Business Combination, Acquisition Related Costs	17	0	[1]	19	2	[1]
Costs Incurred, Development Costs	1	0		1	0
Operating Income	100	84	[1]	293	263	[1]
Equity in earnings of unconsolidated affiliates	32	28	[1]	65	63	[1]
Other income, net	2	1	[1]	4	3	[1]
Gain (Loss) on Extinguishment of Debt	0	0	[1]	0	(2)	[1]
Interest expense	(70)	(71)	[1]	(190)	(229)	[1]
Net Income (Loss)	64	42	[1]	172	98	[1]
Total Assets	8,391			8,391			$ 8,360
Conventional Generation [Member]
Segment Reporting
Operating revenues	87	88		251	246
Cost of operations	12	16		44	53
Depreciation and amortization	26	27		76	77
Asset Impairment Charges		0
General and administrative	0	0		0	0
Business Combination, Acquisition Related Costs	0	0		0	0
Costs Incurred, Development Costs	0			0
Operating Income	49	45		131	116
Equity in earnings of unconsolidated affiliates	3	3		8	9
Other income, net	0	1		1	1
Gain (Loss) on Extinguishment of Debt					0
Interest expense	(13)	(13)		(33)	(39)
Net Income (Loss)	39	36		107	87
Total Assets	1,811			1,811
Corporate
Segment Reporting
Operating revenues	0	0		0	0
Cost of operations	0	0		0	0
Depreciation and amortization	0	0		0	0
Asset Impairment Charges		0
General and administrative	6	4		17	14
Business Combination, Acquisition Related Costs	17	0		19	2
Costs Incurred, Development Costs	1			1
Operating Income	(24)	(4)		(37)	(16)
Equity in earnings of unconsolidated affiliates	0	0		0	0
Other income, net	1	0		1	1
Gain (Loss) on Extinguishment of Debt					0
Interest expense	(17)	(18)		(54)	(53)
Net Income (Loss)	(40)	(22)		(90)	(68)
Total Assets	116			116
Thermal [Member]
Segment Reporting
Operating revenues	53	46		146	130
Cost of operations	33	29		97	86
Depreciation and amortization	6	5		17	15
Asset Impairment Charges		0
General and administrative	0	0		0	0
Business Combination, Acquisition Related Costs	0	0		0	0
Costs Incurred, Development Costs	0			0
Operating Income	14	12		32	29
Equity in earnings of unconsolidated affiliates	0	0		0	0
Other income, net	0	0		0	0
Gain (Loss) on Extinguishment of Debt					0
Interest expense	(4)	(2)		(8)	(7)
Net Income (Loss)	10	10		24	22
Total Assets	512			512
Renewables
Segment Reporting
Operating revenues	152	135		427	402
Cost of operations	39	34		106	102
Depreciation and amortization	52	58		154	154
Asset Impairment Charges		12
General and administrative	0	0		0	0
Business Combination, Acquisition Related Costs	0	0		0	0
Costs Incurred, Development Costs	0			0
Operating Income	61	31		167	134
Equity in earnings of unconsolidated affiliates	29	25		57	54
Other income, net	1	0		2	1
Gain (Loss) on Extinguishment of Debt					(2)
Interest expense	(36)	(38)		(95)	(130)
Net Income (Loss)	55	$ 18		131	$ 57
Total Assets	$ 5,952			$ 5,952
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Related Party Transactions (Det

Related Party Transactions (Details) $ in Millions		2 Months Ended	3 Months Ended			8 Months Ended	9 Months Ended
		Aug. 31, 2018USD ($)	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Aug. 31, 2018USD ($)	Sep. 30, 2018USD ($)MW	Sep. 30, 2017USD ($)		Dec. 31, 2017USD ($)
Related Party Transaction
General and administrative			$ 6	$ 4	[1]		$ 17	$ 14	[1]
Accounts payable — affiliate			22				22			$ 49	[1]
Due to Affiliate, Noncurrent			$ 44				$ 44			618	[1]
Power Generation Capacity, Megawatts | MW	[2],[3]		5,405				5,405
RENOM [Member]
Related Party Transaction
Due to Affiliate			$ 5				$ 5			$ 5
Related Party Transaction, Expenses from Transactions with Related Party			$ 7	5			22	17
NRG [Member]
Related Party Transaction
Revenues		$ 2		3		$ 8		10
NRG Yield [Member] | NRG [Member]
Related Party Transaction
General and administrative		2		2		7		8
Thermal [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party		1		1		7		7
Marsh Landing [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party		2		4		11		10
Operations and Maintenance services [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party		7		10		27		29
Operations and Maintenance services [Member] | GCE Holding LLC [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party		$ 1		$ 1		$ 4		$ 4
Management Service, Base [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party							$ 9
Thermal [Member]
Related Party Transaction
Steam and Chilled Water Capacity, Megawatts Thermal Equivalent | MW	[2],[4]		1,392				1,392
Power Generation Capacity, Megawatts | MW	[2]		133				133
Thermal [Member] | Thermal [Member]
Related Party Transaction
Power Generation Capacity, Megawatts | MW	[2]		30				30
Thermal [Member] | UPMC Thermal [Member]
Related Party Transaction
Steam and Chilled Water Capacity, Megawatts Thermal Equivalent | MW			73				73
Power Generation Capacity, Megawatts | MW			7.5				7.5
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(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 September 30, 2018.
[3]	(c) The Company's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. The Company's generation capacity including this noncontrolling interest was 5,411 MWs.
[4]	(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.

Condensed Consolidating Finan_3

Condensed Consolidating Financial Information CP Income Statement (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018		Sep. 30, 2017		Dec. 31, 2017
Condensed Income Statements, Captions [Line Items]
Costs Incurred, Development Costs		$ 1		$ 0		$ 1		$ 0
Total operating revenues		292		269	[1]	824		778	[1]
Operating Costs and Expenses
Cost of operations		84		79	[1]	247		241	[1]
Depreciation and amortization		84		90	[1]	247		246	[1]
General and administrative		6		4	[1]	17		14	[1]
Total operating costs and expenses		192		185	[1]	531		515	[1]
Operating Income (Loss)		100		84	[1]	293		263	[1]
Costs and Expenses [Abstract]
Equity in earnings (losses) of consolidated affiliates		0		0	[1]	0		0	[1]
Equity in earnings of unconsolidated affiliates		32		28	[1]	65		63	[1]
Other income, net		2		1	[1]	4		3	[1]
Interest expense		70		71	[1]	190		229	[1]
Total other income (expense), net		(36)		(42)	[1]	(121)		(165)	[1]
Net Income (Loss)		64		42	[1]	172		98	[1]
Less: Loss attributable to noncontrolling interests		(2)		(23)	[1]	(95)		(56)	[1]
Net Income Attributable to Clearway Energy LLC		66		65	[1]	267		154	[1]
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Costs Incurred, Development Costs		0				0
Total operating revenues		3		3		9		8
Operating Costs and Expenses
Cost of operations		0		0		1		1
Depreciation and amortization		2		2		4		4
General and administrative		0		0		0		0
Total operating costs and expenses		2		14		5		17
Operating Income (Loss)		1		(11)		4		(9)
Costs and Expenses [Abstract]
Equity in earnings (losses) of consolidated affiliates		7		(4)		19		6
Equity in earnings of unconsolidated affiliates		12		7		32		9
Other income, net		0		0		0		0
Interest expense		0		0		0		1
Total other income (expense), net		19		3		51		14
Net Income (Loss)		20		(8)		55		5
Less: Loss attributable to noncontrolling interests		0		0		0		0
Net Income Attributable to Clearway Energy LLC		20		(8)		55		5
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Costs Incurred, Development Costs		0				0
Total operating revenues		289		266	[1]	815		770	[1]
Operating Costs and Expenses
Cost of operations		84		79	[1]	246		240	[1]
Depreciation and amortization		82		88	[1]	243		242	[1]
General and administrative		0		0	[1]	0		0	[1]
Total operating costs and expenses		166		167	[1]	489		482	[1]
Operating Income (Loss)		123		99	[1]	326		288	[1]
Costs and Expenses [Abstract]
Equity in earnings (losses) of consolidated affiliates		0		0	[1]	0		0	[1]
Equity in earnings of unconsolidated affiliates		3		6	[1]	7		28	[1]
Other income, net		1		1	[1]	3		2	[1]
Interest expense		52		53	[1]	136		176	[1]
Total other income (expense), net		(48)		(46)	[1]	(126)		(146)	[1]
Net Income (Loss)		75		53	[1]	200		142	[1]
Less: Loss attributable to noncontrolling interests		(2)		(1)	[1]	(66)		(3)	[1]
Net Income Attributable to Clearway Energy LLC		77		54	[1]	266		145	[1]
NRG Yield LLC [Member]
Condensed Income Statements, Captions [Line Items]
Costs Incurred, Development Costs		0				0
Total operating revenues		0		0	[1]	0		0	[1]
Operating Costs and Expenses
Cost of operations		0		0	[1]	0		0	[1]
Depreciation and amortization		0		0	[1]	0		0	[1]
General and administrative		0		0	[1]	0		0	[1]
Total operating costs and expenses		0		0	[1]	0		0	[1]
Operating Income (Loss)		0		0	[1]	0		0	[1]
Costs and Expenses [Abstract]
Equity in earnings (losses) of consolidated affiliates		65		65	[1]	266		153	[1]
Equity in earnings of unconsolidated affiliates		0		0	[1]	0		0	[1]
Other income, net		1		0	[1]	1		1	[1]
Interest expense		0		0	[1]	0		0	[1]
Total other income (expense), net		66		65	[1]	267		154	[1]
Net Income (Loss)		66		65	[1]	267		154	[1]
Less: Loss attributable to noncontrolling interests		0		0	[1]	0		0	[1]
Net Income Attributable to Clearway Energy LLC		66		65	[1]	267		154	[1]
NRG Yield Operating LLC [Member]
Condensed Income Statements, Captions [Line Items]
Costs Incurred, Development Costs		1				1
Total operating revenues		1		0	[1]	2		1	[1]
Operating Costs and Expenses
Cost of operations		1		0	[1]	2		1	[1]
Depreciation and amortization		0		0	[1]	0		0	[1]
General and administrative		6		4	[1]	17		14	[1]
Total operating costs and expenses		25		4	[1]	39		17	[1]
Operating Income (Loss)		(24)		(4)	[1]	(37)		(16)	[1]
Costs and Expenses [Abstract]
Equity in earnings (losses) of consolidated affiliates		88		49	[1]	236		141	[1]
Equity in earnings of unconsolidated affiliates		17		15	[1]	26		26	[1]
Other income, net		0		0	[1]	0		0	[1]
Interest expense		18		18	[1]	54		54	[1]
Total other income (expense), net		87		46	[1]	208		113	[1]
Net Income (Loss)		63		42	[1]	171		97	[1]
Less: Loss attributable to noncontrolling interests		(2)		(23)	[1]	(95)		(56)	[1]
Net Income Attributable to Clearway Energy LLC		65		65	[1]	266		153	[1]
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Costs Incurred, Development Costs	[2]	0				0
Total operating revenues		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Operating Costs and Expenses
Cost of operations		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Depreciation and amortization		0	[2]	0	[3]	0	[2]	0	[3]
General and administrative		0	[2]	0	[3]	0	[2]	0	[3]
Total operating costs and expenses		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Operating Income (Loss)		0	[2]	0	[3]	0	[2]	0	[3]
Costs and Expenses [Abstract]
Equity in earnings (losses) of consolidated affiliates		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3]
Equity in earnings of unconsolidated affiliates		0	[2]	0	[3]	0	[2]	0	[3]
Other income, net		0	[2]	0	[3]	0	[2]	0	[3]
Interest expense		0	[2]	0	[3]	0	[2]	0	[3]
Total other income (expense), net		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3]
Net Income (Loss)		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3],[4]
Less: Loss attributable to noncontrolling interests		2	[2]	1	[3]	66	[2]	3	[3]
Net Income Attributable to Clearway Energy LLC		(162)	[2]	$ (111)	[3]	(587)	[2]	$ (303)	[3]
5.00% Senior Notes due in 2026 [Member]
Condensed Income Statements, Captions [Line Items]
Senior Notes		$ 350				$ 350				$ 350
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.
[4]	(b) All significant intercompany transactions have been eliminated in consolidation.

Condensed Consolidating Finan_4

Condensed Consolidating Financial Information CP Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018		Sep. 30, 2017
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	$ 64		$ 42	[1]	$ 172		$ 98	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	7		7	[1]	34		7	[1]
Other Comprehensive Income (Loss), Net of Tax	7		7	[1]	34		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	71		49	[1]	206		105	[1]
Less: Comprehensive loss attributable to noncontrolling interests	(2)		(23)	[1]	(95)		(56)	[1]
Comprehensive Income Attributable to NRG Yield LLC	73		72	[1]	301		161	[1]
Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	20		(8)		55		5
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	0		0		1		0
Other Comprehensive Income (Loss), Net of Tax	0		0		1		0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	20		(8)		56		5
Less: Comprehensive loss attributable to noncontrolling interests	0		0		0		0
Comprehensive Income Attributable to NRG Yield LLC	20		(8)		56		5
Non-Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	75		53	[1]	200		142	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	8		7	[1]	30		7	[1]
Other Comprehensive Income (Loss), Net of Tax	8		7	[1]	30		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	83		60	[1]	230		149	[1]
Less: Comprehensive loss attributable to noncontrolling interests	(2)		(1)	[1]	(66)		(3)	[1]
Comprehensive Income Attributable to NRG Yield LLC	85		61	[1]	296		152	[1]
NRG Yield LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	66		65	[1]	267		154	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	7		7	[1]	34		7	[1]
Other Comprehensive Income (Loss), Net of Tax	7		7	[1]	34		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	73		72	[1]	301		161	[1]
Less: Comprehensive loss attributable to noncontrolling interests	0		0	[1]	0		0	[1]
Comprehensive Income Attributable to NRG Yield LLC	73		72	[1]	301		161	[1]
NRG Yield Operating LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	63		42	[1]	171		97	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	7		7	[1]	34		7	[1]
Other Comprehensive Income (Loss), Net of Tax	7		7	[1]	34		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	70		49	[1]	205		104	[1]
Less: Comprehensive loss attributable to noncontrolling interests	(2)		(23)	[1]	(95)		(56)	[1]
Comprehensive Income Attributable to NRG Yield LLC	72		72	[1]	300		160	[1]
Consolidation, Eliminations [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3],[4]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(15)	[2]	(14)	[4]	(65)	[2]	(14)	[4]
Other Comprehensive Income (Loss), Net of Tax	(15)	[2]	(14)	[4]	(65)	[2]	(14)	[4]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(175)	[2]	(124)	[4]	(586)	[2]	(314)	[4]
Less: Comprehensive loss attributable to noncontrolling interests	2	[5]	1	[4]	66	[5]	3	[4]
Comprehensive Income Attributable to NRG Yield LLC	$ (177)	[5]	$ (125)	[4]	$ (652)	[5]	$ (317)	[4]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.
[4]	(b) All significant intercompany transactions have been eliminated in consolidation.
[5]	(a) All significant intercompany transactions have been eliminated in consolidation.

Condensed Consolidating Finan_5

Condensed Consolidating Financial Information CP Balance Sheet (Details) - USD ($)		Sep. 30, 2018		Dec. 31, 2017
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		$ 231,000,000		$ 146,000,000	[1]
Restricted cash		157,000,000		168,000,000	[1]
Accounts receivable — trade		141,000,000		95,000,000	[1]
Accounts receivable — affiliate		0		1,000,000	[1]
Inventory		39,000,000		39,000,000	[1]
Notes receivable		3,000,000		13,000,000	[1]
Prepayments and other current assets		31,000,000		19,000,000	[1]
Total current assets		602,000,000		481,000,000	[1]
Net property, plant and equipment		5,306,000,000		5,410,000,000	[1]
Investment in consolidated subsidiaries		0		0	[1]
Equity investments in affiliates		1,182,000,000		1,178,000,000	[1]
Intangible assets, net		1,177,000,000		1,228,000,000	[1]
Derivative Asset, Noncurrent		32,000,000		1,000,000	[1]
Other non-current assets		92,000,000		62,000,000	[1]
Other Assets		2,483,000,000		2,469,000,000	[1]
Total Assets		8,391,000,000		8,360,000,000	[1]
Current portion of long-term debt — external		309,000,000		339,000,000	[1]
Affiliate Current Debt		559,000,000		0	[1]
Accounts payable — trade		90,000,000		46,000,000	[1]
Accounts payable — affiliate		22,000,000		49,000,000	[1]
Derivative instruments		5,000,000		18,000,000	[1]
Accrued expenses and other current liabilities		95,000,000		87,000,000	[1]
Current Liabilities		1,080,000,000		539,000,000	[1]
Other Liabilities
Long-term debt — external		4,888,000,000		5,049,000,000	[1]
Long-term debt — affiliate		44,000,000		618,000,000	[1]
Derivative instruments		9,000,000		31,000,000	[1]
Other non-current liabilities		97,000,000		94,000,000	[1]
Total non-current liabilities		5,038,000,000		5,792,000,000	[1]
Total Liabilities		6,118,000,000		6,331,000,000	[1]
Commitments and Contingencies		0		0
Contributed capital		1,937,000,000		1,919,000,000	[1]
Retained earnings		177,000,000		16,000,000	[1]
Noncontrolling interest		193,000,000		162,000,000	[1]
Accumulated other comprehensive loss		(34,000,000)		(68,000,000)	[1]
Stockholders' Equity Attributable to Noncontrolling Interest		193,000,000		162,000,000	[1]
Total Members' Equity		2,273,000,000		2,029,000,000	[1]
Total Liabilities and Members’ Equity		8,391,000,000		8,360,000,000	[1]
Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		0		0
Restricted cash		0		0
Accounts receivable — trade		3,000,000		1,000,000
Accounts receivable — affiliate				0
Inventory		0		0
Notes receivable		0		0
Prepayments and other current assets		0		0
Total current assets		3,000,000		1,000,000
Net property, plant and equipment		67,000,000		59,000,000
Investment in consolidated subsidiaries		443,000,000		460,000,000
Equity investments in affiliates		268,000,000		233,000,000
Intangible assets, net		11,000,000		12,000,000
Derivative Asset, Noncurrent		0
Other non-current assets		0		0
Other Assets		722,000,000		705,000,000
Total Assets		792,000,000		765,000,000
Current portion of long-term debt — external		0		0
Affiliate Current Debt		0
Accounts payable — trade		0		0
Accounts payable — affiliate		1,000,000		0
Derivative instruments		0		0
Accrued expenses and other current liabilities		0
Current Liabilities		1,000,000		0
Other Liabilities
Long-term debt — external		0		0
Long-term debt — affiliate		0		0
Derivative instruments		0		0
Other non-current liabilities		2,000,000		2,000,000
Total non-current liabilities		2,000,000		2,000,000
Total Liabilities		3,000,000		2,000,000
Contributed capital		797,000,000		822,000,000
Retained earnings		(8,000,000)		(58,000,000)
Accumulated other comprehensive loss		0		(1,000,000)
Stockholders' Equity Attributable to Noncontrolling Interest		0		0
Total Members' Equity		789,000,000		763,000,000
Total Liabilities and Members’ Equity		792,000,000		765,000,000
Non-Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		120,000,000		124,000,000	[1]
Restricted cash		157,000,000		168,000,000	[1]
Accounts receivable — trade		138,000,000		93,000,000	[1]
Accounts receivable — affiliate	[1]			0
Inventory		39,000,000		39,000,000	[1]
Notes receivable		3,000,000		13,000,000	[1]
Prepayments and other current assets		29,000,000		18,000,000	[1]
Total current assets		486,000,000		455,000,000	[1]
Net property, plant and equipment		5,239,000,000		5,351,000,000	[1]
Investment in consolidated subsidiaries		0		0	[1]
Equity investments in affiliates		544,000,000		577,000,000	[1]
Intangible assets, net		1,166,000,000		1,216,000,000	[1]
Derivative Asset, Noncurrent		32,000,000
Other non-current assets		89,000,000		62,000,000	[1]
Other Assets		1,831,000,000		1,856,000,000	[1]
Total Assets		7,556,000,000		7,662,000,000	[1]
Current portion of long-term debt — external		309,000,000		339,000,000	[1]
Affiliate Current Debt		0
Accounts payable — trade		67,000,000		46,000,000	[1]
Accounts payable — affiliate		10,000,000		33,000,000	[1]
Derivative instruments		5,000,000		18,000,000	[1]
Accrued expenses and other current liabilities		80,000,000		62,000,000	[1]
Current Liabilities		471,000,000		498,000,000	[1]
Other Liabilities
Long-term debt — external		4,047,000,000		4,153,000,000	[1]
Long-term debt — affiliate		0		0	[1]
Derivative instruments		9,000,000		31,000,000	[1]
Other non-current liabilities		87,000,000		85,000,000	[1]
Total non-current liabilities		4,143,000,000		4,269,000,000	[1]
Total Liabilities		4,614,000,000		4,767,000,000	[1]
Contributed capital		2,732,000,000		2,934,000,000	[1]
Retained earnings		144,000,000		(25,000,000)	[1]
Accumulated other comprehensive loss		(41,000,000)		(71,000,000)	[1]
Stockholders' Equity Attributable to Noncontrolling Interest		107,000,000		57,000,000	[1]
Total Members' Equity		2,942,000,000		2,895,000,000	[1]
Total Liabilities and Members’ Equity		7,556,000,000		7,662,000,000	[1]
NRG Yield LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		111,000,000		22,000,000	[1]
Restricted cash		0		0	[1]
Accounts receivable — trade		0		0	[1]
Accounts receivable — affiliate	[1]			1,000,000
Inventory		0		0	[1]
Notes receivable		0		0	[1]
Prepayments and other current assets		0		0	[1]
Total current assets		111,000,000		23,000,000	[1]
Net property, plant and equipment				0	[1]
Investment in consolidated subsidiaries		1,969,000,000		1,844,000,000	[1]
Equity investments in affiliates		0		0	[1]
Intangible assets, net		0		0	[1]
Derivative Asset, Noncurrent		0
Other non-current assets		0		0	[1]
Other Assets		1,969,000,000		1,844,000,000	[1]
Total Assets		2,080,000,000		1,867,000,000	[1]
Current portion of long-term debt — external		0		0	[1]
Affiliate Current Debt		0
Accounts payable — trade		0		0	[1]
Accounts payable — affiliate		0		0	[1]
Derivative instruments		0		0	[1]
Accrued expenses and other current liabilities		0		0	[1]
Current Liabilities		0		0	[1]
Other Liabilities
Long-term debt — external		0		0	[1]
Long-term debt — affiliate		0		0	[1]
Derivative instruments		0		0	[1]
Other non-current liabilities		0		0	[1]
Total non-current liabilities		0		0	[1]
Total Liabilities		0		0	[1]
Contributed capital		1,937,000,000		1,919,000,000	[1]
Retained earnings		177,000,000		16,000,000	[1]
Accumulated other comprehensive loss		(34,000,000)		(68,000,000)	[1]
Stockholders' Equity Attributable to Noncontrolling Interest		0		0	[1]
Total Members' Equity		2,080,000,000		1,867,000,000	[1]
Total Liabilities and Members’ Equity		2,080,000,000		1,867,000,000
NRG Yield Operating LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		0		0	[1]
Restricted cash		0		0	[1]
Accounts receivable — trade		0		1,000,000	[1]
Accounts receivable — affiliate	[1]			0
Inventory		0		0	[1]
Notes receivable		0		0	[1]
Prepayments and other current assets		2,000,000		1,000,000	[1]
Total current assets		2,000,000		2,000,000	[1]
Net property, plant and equipment				0	[1]
Investment in consolidated subsidiaries		3,288,000,000		3,198,000,000	[1]
Equity investments in affiliates		370,000,000		368,000,000	[1]
Intangible assets, net		0		0	[1]
Derivative Asset, Noncurrent		0
Other non-current assets		3,000,000		0	[1]
Other Assets		3,661,000,000		3,566,000,000	[1]
Total Assets		3,663,000,000		3,568,000,000	[1]
Current portion of long-term debt — external		0		0	[1]
Affiliate Current Debt		559,000,000
Accounts payable — trade		23,000,000		0	[1]
Accounts payable — affiliate		11,000,000		16,000,000	[1]
Derivative instruments		0		0	[1]
Accrued expenses and other current liabilities		15,000,000		25,000,000	[1]
Current Liabilities		608,000,000		41,000,000	[1]
Other Liabilities
Long-term debt — external		841,000,000		896,000,000	[1]
Long-term debt — affiliate		44,000,000		618,000,000	[1]
Derivative instruments		0		0	[1]
Other non-current liabilities		8,000,000		7,000,000	[1]
Total non-current liabilities		893,000,000		1,521,000,000	[1]
Total Liabilities		1,501,000,000		1,562,000,000	[1]
Contributed capital		2,119,000,000		2,119,000,000	[1]
Retained earnings		(116,000,000)		(207,000,000)	[1]
Accumulated other comprehensive loss		(34,000,000)		(68,000,000)	[1]
Stockholders' Equity Attributable to Noncontrolling Interest		193,000,000		162,000,000	[1]
Total Members' Equity		2,162,000,000		2,006,000,000	[1]
Total Liabilities and Members’ Equity		3,663,000,000		3,568,000,000	[1]
Consolidation, Eliminations [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		0	[2]	0	[3]
Restricted cash		0	[2]	0	[3]
Accounts receivable — trade		0	[2]	0	[3]
Accounts receivable — affiliate	[3]			0
Inventory		0	[2]	0	[3]
Notes receivable		0	[2]	0	[3]
Prepayments and other current assets		0	[2]	0	[3]
Total current assets		0	[2]	0	[3]
Net property, plant and equipment			[2]	0	[3]
Investment in consolidated subsidiaries		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Equity investments in affiliates		0	[2]	0	[3]
Intangible assets, net		0	[2]	0	[3]
Derivative Asset, Noncurrent	[2]	0
Other non-current assets		0	[2]	0	[3]
Other Assets		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Total Assets		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Current portion of long-term debt — external		0	[2]	0	[3]
Affiliate Current Debt	[2]	0
Accounts payable — trade		0	[2]	0	[3]
Accounts payable — affiliate		0	[2]	0	[3]
Derivative instruments		0	[2]	0	[3]
Accrued expenses and other current liabilities		0	[2]	0	[3]
Current Liabilities		0	[2]	0	[3]
Other Liabilities
Long-term debt — external		0	[2]	0	[3]
Long-term debt — affiliate		0	[2]	0	[3]
Derivative instruments		0	[2]	0	[3]
Other non-current liabilities		0	[2]	0	[3]
Total non-current liabilities		0	[2]	0	[3]
Total Liabilities		0	[2]	0	[3]
Contributed capital		(5,648,000,000)	[2]	(5,875,000,000)	[3]
Retained earnings		(20,000,000)	[2]	290,000,000	[3]
Accumulated other comprehensive loss		75,000,000	[2]	140,000,000	[3]
Stockholders' Equity Attributable to Noncontrolling Interest		(107,000,000)	[2]	(57,000,000)	[3]
Total Members' Equity		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Total Liabilities and Members’ Equity		$ (5,700,000,000)	[2]	$ (5,502,000,000)	[3]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.

Condensed Consolidating Finan_6

Condensed Consolidating Financial Information CP Cash Flows (Details) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017
Condensed Cash Flow Statements, Captions [Line Items]
Repayments of Related Party Debt		$ (16)	$ 0
Net contributions from noncontrolling interests		108	13	[1]
Net Cash Provided by (Used in) Operating Activities		397	374	[1]
Intercompany transactions between Clearway Energy LLC and subsidiaries		0	0	[1]
Payments for the Drop Down Assets		126	176	[1]
Capital expenditures		(62)	(102)	[1]
Cash receipts from notes receivable		10	11	[1]
Return of investment from unconsolidated affiliates		22	32	[1]
Investments in unconsolidated affiliates		(16)	(48)	[1]
Payments for (Proceeds from) Other Investing Activities		(8)	0	[1]
Net Cash Used in Investing Activities		(175)	(283)	[1]
Transfer of funds under intercompany cash management arrangement		0	0	[1]
Net contributions from noncontrolling interests	[1]		13
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets		0	(26)	[1]
Proceeds from issuance of Class C units		151	33	[1]
Payments of (Proceeds from) distributions		189	149	[1]
Proceeds from the issuance of long-term debt — external		227	130	[1]
Net Cash (Used in) Provided by Financing Activities		(148)	(266)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash		74	(175)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		314	497	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period		388	322	[1]
Proceeds from the revolving credit facility		35	0	[1]
Repayments of Lines of Credit		90	0	[1]
Payments to Acquire Businesses, Net of Cash Acquired		11	0	[1]
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Repayments of Related Party Debt		0
Net contributions from noncontrolling interests		0
Net Cash Provided by (Used in) Operating Activities		9	34
Intercompany transactions between Clearway Energy LLC and subsidiaries		0	0
Payments for the Drop Down Assets		0
Capital expenditures		0	0
Cash receipts from notes receivable		0	0
Return of investment from unconsolidated affiliates		7	7
Investments in unconsolidated affiliates		(16)	(41)
Payments for (Proceeds from) Other Investing Activities		0
Net Cash Used in Investing Activities		(9)	(34)
Transfer of funds under intercompany cash management arrangement		0	(1)
Net contributions from noncontrolling interests			0
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets			(25)
Proceeds from issuance of Class C units		0	0
Payments of (Proceeds from) distributions		0	0
Proceeds from the issuance of long-term debt — external		0	0
Net Cash (Used in) Provided by Financing Activities		0	(6)
Net Decrease in Cash, Cash Equivalents and Restricted Cash		0	(6)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		0	9
Cash, Cash Equivalents and Restricted Cash at End of Period		0	3
Proceeds from the revolving credit facility		0
Repayments of Lines of Credit		0
Payments to Acquire Businesses, Net of Cash Acquired		0
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Repayments of Related Party Debt		0
Net contributions from noncontrolling interests		98
Net Cash Provided by (Used in) Operating Activities		429	417	[1]
Intercompany transactions between Clearway Energy LLC and subsidiaries		0	0	[1]
Payments for the Drop Down Assets		0
Capital expenditures		(62)	(102)	[1]
Cash receipts from notes receivable		10	11	[1]
Return of investment from unconsolidated affiliates		11	9	[1]
Investments in unconsolidated affiliates		0	(7)	[1]
Payments for (Proceeds from) Other Investing Activities		(8)
Net Cash Used in Investing Activities		(33)	(89)	[1]
Transfer of funds under intercompany cash management arrangement		(3)	0	[1]
Net contributions from noncontrolling interests	[1]		0
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets	[1]		(44)
Proceeds from issuance of Class C units		0	0	[1]
Payments of (Proceeds from) distributions		362	211	[1]
Proceeds from the issuance of long-term debt — external		227	130	[1]
Net Cash (Used in) Provided by Financing Activities		(411)	(362)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash		(15)	(34)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		292	277	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period		277	243	[1]
Proceeds from the revolving credit facility		0
Repayments of Lines of Credit		0
Payments to Acquire Businesses, Net of Cash Acquired		0
NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Repayments of Related Party Debt		0
Net contributions from noncontrolling interests		0
Net Cash Provided by (Used in) Operating Activities		0	0	[1]
Intercompany transactions between Clearway Energy LLC and subsidiaries		108	(13)	[1]
Payments for the Drop Down Assets		0
Capital expenditures		0	0	[1]
Cash receipts from notes receivable		0	0	[1]
Return of investment from unconsolidated affiliates		0	0	[1]
Investments in unconsolidated affiliates		0	0	[1]
Payments for (Proceeds from) Other Investing Activities		0
Net Cash Used in Investing Activities		108	(13)	[1]
Transfer of funds under intercompany cash management arrangement		4	(6)	[1]
Net contributions from noncontrolling interests	[1]		0
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets	[1]		0
Proceeds from issuance of Class C units		151	33	[1]
Payments of (Proceeds from) distributions		174	149	[1]
Proceeds from the issuance of long-term debt — external		0	0	[1]
Net Cash (Used in) Provided by Financing Activities		(19)	(122)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash		89	(135)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		22	211	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period		111	76	[1]
Proceeds from the revolving credit facility		0
Repayments of Lines of Credit		0
Payments to Acquire Businesses, Net of Cash Acquired		0
NRG Yield Operating LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Repayments of Related Party Debt		(16)
Net contributions from noncontrolling interests		10
Net Cash Provided by (Used in) Operating Activities		(41)	(77)
Intercompany transactions between Clearway Energy LLC and subsidiaries		(108)	13
Payments for the Drop Down Assets		126	176
Capital expenditures		0	0
Cash receipts from notes receivable		0	0
Return of investment from unconsolidated affiliates		4	16
Investments in unconsolidated affiliates		0	0
Payments for (Proceeds from) Other Investing Activities		0
Net Cash Used in Investing Activities		(241)	(147)
Transfer of funds under intercompany cash management arrangement		(1)	7
Net contributions from noncontrolling interests			13
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets			(7)
Proceeds from issuance of Class C units		0
Payments of (Proceeds from) distributions		(347)	(211)
Proceeds from the issuance of long-term debt — external		0	0
Net Cash (Used in) Provided by Financing Activities		282	224
Net Decrease in Cash, Cash Equivalents and Restricted Cash		0	0
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		0	0
Cash, Cash Equivalents and Restricted Cash at End of Period		0	$ 0
Proceeds from the revolving credit facility		35
Repayments of Lines of Credit		90
Payments to Acquire Businesses, Net of Cash Acquired		$ 11
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.

Condensed Consolidating Finan_7

Condensed Consolidating Financial Information PP Income Statement (Details) - USD ($) $ in Millions		3 Months Ended				9 Months Ended
		Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018		Sep. 30, 2017
Condensed Income Statements, Captions [Line Items]
Total operating revenues		$ 292		$ 269	[1]	$ 824		$ 778	[1]
Operating Costs and Expenses
Cost of operations		84		79	[1]	247		241	[1]
Depreciation and amortization		84		90	[1]	247		246	[1]
Asset Impairment Charges		0		12		0		12
General and administrative		6		4	[1]	17		14	[1]
Business Combination, Acquisition Related Costs		17		0	[1]	19		2	[1]
Total operating costs and expenses		192		185	[1]	531		515	[1]
Operating Income (Loss)		100		84	[1]	293		263	[1]
Equity in earnings (losses) of consolidated affiliates		0		0	[1]	0		0	[1]
Equity in earnings of unconsolidated affiliates		32		28	[1]	65		63	[1]
Other income, net		2		1	[1]	4		3	[1]
Gain (Loss) on Extinguishment of Debt		0		0	[1]	0		(2)	[1]
Interest expense		70		71	[1]	190		229	[1]
Total other income (expense), net		(36)		(42)	[1]	(121)		(165)	[1]
Net Income (Loss)		64		42	[1]	172		98	[1]
Less: Loss attributable to noncontrolling interests		(2)		(23)	[1]	(95)		(56)	[1]
Net Income Attributable to Clearway Energy LLC		66		65	[1]	267		154	[1]
Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues		3		3		9		8
Operating Costs and Expenses
Cost of operations		0		0		1		1
Depreciation and amortization		2		2		4		4
Asset Impairment Charges				12				12
General and administrative		0		0		0		0
Business Combination, Acquisition Related Costs		0				0		0
Total operating costs and expenses		2		14		5		17
Operating Income (Loss)		1		(11)		4		(9)
Equity in earnings (losses) of consolidated affiliates		7		(4)		19		6
Equity in earnings of unconsolidated affiliates		12		7		32		9
Other income, net		0		0		0		0
Gain (Loss) on Extinguishment of Debt								(2)
Interest expense		0		0		0		1
Total other income (expense), net		19		3		51		14
Net Income (Loss)		20		(8)		55		5
Less: Loss attributable to noncontrolling interests		0		0		0		0
Net Income Attributable to Clearway Energy LLC		20		(8)		55		5
Non-Guarantor Subsidiaries [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues		289		266	[1]	815		770	[1]
Operating Costs and Expenses
Cost of operations		84		79	[1]	246		240	[1]
Depreciation and amortization		82		88	[1]	243		242	[1]
Asset Impairment Charges				0				0
General and administrative		0		0	[1]	0		0	[1]
Business Combination, Acquisition Related Costs		0				0		0	[1]
Total operating costs and expenses		166		167	[1]	489		482	[1]
Operating Income (Loss)		123		99	[1]	326		288	[1]
Equity in earnings (losses) of consolidated affiliates		0		0	[1]	0		0	[1]
Equity in earnings of unconsolidated affiliates		3		6	[1]	7		28	[1]
Other income, net		1		1	[1]	3		2	[1]
Gain (Loss) on Extinguishment of Debt	[1]							0
Interest expense		52		53	[1]	136		176	[1]
Total other income (expense), net		(48)		(46)	[1]	(126)		(146)	[1]
Net Income (Loss)		75		53	[1]	200		142	[1]
Less: Loss attributable to noncontrolling interests		(2)		(1)	[1]	(66)		(3)	[1]
Net Income Attributable to Clearway Energy LLC		77		54	[1]	266		145	[1]
NRG Yield LLC [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues		0		0	[1]	0		0	[1]
Operating Costs and Expenses
Cost of operations		0		0	[1]	0		0	[1]
Depreciation and amortization		0		0	[1]	0		0	[1]
Asset Impairment Charges				0				0
General and administrative		0		0	[1]	0		0	[1]
Business Combination, Acquisition Related Costs		0				0		0	[1]
Total operating costs and expenses		0		0	[1]	0		0	[1]
Operating Income (Loss)		0		0	[1]	0		0	[1]
Equity in earnings (losses) of consolidated affiliates		65		65	[1]	266		153	[1]
Equity in earnings of unconsolidated affiliates		0		0	[1]	0		0	[1]
Other income, net		1		0	[1]	1		1	[1]
Gain (Loss) on Extinguishment of Debt	[1]							0
Interest expense		0		0	[1]	0		0	[1]
Total other income (expense), net		66		65	[1]	267		154	[1]
Net Income (Loss)		66		65	[1]	267		154	[1]
Less: Loss attributable to noncontrolling interests		0		0	[1]	0		0	[1]
Net Income Attributable to Clearway Energy LLC		66		65	[1]	267		154	[1]
NRG Yield Operating LLC [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues		1		0	[1]	2		1	[1]
Operating Costs and Expenses
Cost of operations		1		0	[1]	2		1	[1]
Depreciation and amortization		0		0	[1]	0		0	[1]
Asset Impairment Charges				0				0
General and administrative		6		4	[1]	17		14	[1]
Business Combination, Acquisition Related Costs		17				19		2	[1]
Total operating costs and expenses		25		4	[1]	39		17	[1]
Operating Income (Loss)		(24)		(4)	[1]	(37)		(16)	[1]
Equity in earnings (losses) of consolidated affiliates		88		49	[1]	236		141	[1]
Equity in earnings of unconsolidated affiliates		17		15	[1]	26		26	[1]
Other income, net		0		0	[1]	0		0	[1]
Gain (Loss) on Extinguishment of Debt	[1]							0
Interest expense		18		18	[1]	54		54	[1]
Total other income (expense), net		87		46	[1]	208		113	[1]
Net Income (Loss)		63		42	[1]	171		97	[1]
Less: Loss attributable to noncontrolling interests		(2)		(23)	[1]	(95)		(56)	[1]
Net Income Attributable to Clearway Energy LLC		65		65	[1]	266		153	[1]
Consolidation, Eliminations [Member]
Condensed Income Statements, Captions [Line Items]
Total operating revenues		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Operating Costs and Expenses
Cost of operations		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Depreciation and amortization		0	[2]	0	[3]	0	[2]	0	[3]
Asset Impairment Charges				0				0
General and administrative		0	[2]	0	[3]	0	[2]	0	[3]
Business Combination, Acquisition Related Costs		0	[2]			0	[2]	0	[3]
Total operating costs and expenses		(1)	[2]	0	[3]	(2)	[2]	(1)	[3]
Operating Income (Loss)		0	[2]	0	[3]	0	[2]	0	[3]
Equity in earnings (losses) of consolidated affiliates		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3]
Equity in earnings of unconsolidated affiliates		0	[2]	0	[3]	0	[2]	0	[3]
Other income, net		0	[2]	0	[3]	0	[2]	0	[3]
Gain (Loss) on Extinguishment of Debt	[3]							0
Interest expense		0	[2]	0	[3]	0	[2]	0	[3]
Total other income (expense), net		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3]
Net Income (Loss)		(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3],[4]
Less: Loss attributable to noncontrolling interests		2	[2]	1	[3]	66	[2]	3	[3]
Net Income Attributable to Clearway Energy LLC		$ (162)	[2]	$ (111)	[3]	$ (587)	[2]	$ (303)	[3]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.
[4]	(b) All significant intercompany transactions have been eliminated in consolidation.

Condensed Consolidating Finan_8

Condensed Consolidating Financial Information PP Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended				9 Months Ended
	Sep. 30, 2018		Sep. 30, 2017		Sep. 30, 2018		Sep. 30, 2017
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	$ 64		$ 42	[1]	$ 172		$ 98	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	7		7	[1]	34		7	[1]
Other Comprehensive Income (Loss), Net of Tax	7		7	[1]	34		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	71		49	[1]	206		105	[1]
Less: Comprehensive loss attributable to noncontrolling interests	(2)		(23)	[1]	(95)		(56)	[1]
Comprehensive Income Attributable to NRG Yield LLC	73		72	[1]	301		161	[1]
Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	20		(8)		55		5
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	0		0		1		0
Other Comprehensive Income (Loss), Net of Tax	0		0		1		0
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	20		(8)		56		5
Less: Comprehensive loss attributable to noncontrolling interests	0		0		0		0
Comprehensive Income Attributable to NRG Yield LLC	20		(8)		56		5
Non-Guarantor Subsidiaries [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	75		53	[1]	200		142	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	8		7	[1]	30		7	[1]
Other Comprehensive Income (Loss), Net of Tax	8		7	[1]	30		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	83		60	[1]	230		149	[1]
Less: Comprehensive loss attributable to noncontrolling interests	(2)		(1)	[1]	(66)		(3)	[1]
Comprehensive Income Attributable to NRG Yield LLC	85		61	[1]	296		152	[1]
NRG Yield LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	66		65	[1]	267		154	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	7		7	[1]	34		7	[1]
Other Comprehensive Income (Loss), Net of Tax	7		7	[1]	34		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	73		72	[1]	301		161	[1]
Less: Comprehensive loss attributable to noncontrolling interests	0		0	[1]	0		0	[1]
Comprehensive Income Attributable to NRG Yield LLC	73		72	[1]	301		161	[1]
NRG Yield Operating LLC [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	63		42	[1]	171		97	[1]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	7		7	[1]	34		7	[1]
Other Comprehensive Income (Loss), Net of Tax	7		7	[1]	34		7	[1]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	70		49	[1]	205		104	[1]
Less: Comprehensive loss attributable to noncontrolling interests	(2)		(23)	[1]	(95)		(56)	[1]
Comprehensive Income Attributable to NRG Yield LLC	72		72	[1]	300		160	[1]
Consolidation, Eliminations [Member]
Condensed Statement of Income Captions [Line Items]
Net Income (Loss)	(160)	[2]	(110)	[3]	(521)	[2]	(300)	[3],[4]
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	(15)	[2]	(14)	[4]	(65)	[2]	(14)	[4]
Other Comprehensive Income (Loss), Net of Tax	(15)	[2]	(14)	[4]	(65)	[2]	(14)	[4]
Comprehensive Income (Loss), Net of Tax, Including Portion Attributable to Noncontrolling Interest	(175)	[2]	(124)	[4]	(586)	[2]	(314)	[4]
Less: Comprehensive loss attributable to noncontrolling interests	2	[5]	1	[4]	66	[5]	3	[4]
Comprehensive Income Attributable to NRG Yield LLC	$ (177)	[5]	$ (125)	[4]	$ (652)	[5]	$ (317)	[4]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.
[4]	(b) All significant intercompany transactions have been eliminated in consolidation.
[5]	(a) All significant intercompany transactions have been eliminated in consolidation.

Condensed Consolidating Finan_9

Condensed Consolidating Financial Information PP Balance Sheet (Details) - USD ($)		Sep. 30, 2018		Dec. 31, 2017
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		$ 231,000,000		$ 146,000,000	[1]
Restricted cash		157,000,000		168,000,000	[1]
Accounts receivable — trade		141,000,000		95,000,000	[1]
Accounts receivable — affiliate		0		1,000,000	[1]
Inventory		39,000,000		39,000,000	[1]
Notes receivable		3,000,000		13,000,000	[1]
Prepayments and other current assets		31,000,000		19,000,000	[1]
Total current assets		602,000,000		481,000,000	[1]
Net property, plant and equipment		5,306,000,000		5,410,000,000	[1]
Investment in consolidated subsidiaries		0		0	[1]
Equity investments in affiliates		1,182,000,000		1,178,000,000	[1]
Intangible assets, net		1,177,000,000		1,228,000,000	[1]
Derivative Instruments and Hedges, Noncurrent	[1]			1,000,000
Other non-current assets		92,000,000		62,000,000	[1]
Other Assets		2,483,000,000		2,469,000,000	[1]
Total Assets		8,391,000,000		8,360,000,000	[1]
Current portion of long-term debt — external		309,000,000		339,000,000	[1]
Accounts payable — trade		90,000,000		46,000,000	[1]
Accounts payable — affiliate		22,000,000		49,000,000	[1]
Derivative instruments		5,000,000		18,000,000	[1]
Accrued expenses and other current liabilities		95,000,000		87,000,000	[1]
Current Liabilities		1,080,000,000		539,000,000	[1]
Other Liabilities
Long-term debt — external		4,888,000,000		5,049,000,000	[1]
Long-term debt — affiliate		44,000,000		618,000,000	[1]
Derivative instruments		9,000,000		31,000,000	[1]
Other non-current liabilities		97,000,000		94,000,000	[1]
Total non-current liabilities		5,038,000,000		5,792,000,000	[1]
Total Liabilities		6,118,000,000		6,331,000,000	[1]
Commitments and Contingencies		0		0
Contributed capital		1,937,000,000		1,919,000,000	[1]
Retained earnings		177,000,000		16,000,000	[1]
Accumulated other comprehensive loss		(34,000,000)		(68,000,000)	[1]
Noncontrolling interest		193,000,000		162,000,000	[1]
Total Members' Equity		2,273,000,000		2,029,000,000	[1]
Total Liabilities and Members’ Equity		8,391,000,000		8,360,000,000	[1]
Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		0		0
Restricted cash		0		0
Accounts receivable — trade		3,000,000		1,000,000
Accounts receivable — affiliate				0
Inventory		0		0
Notes receivable		0		0
Prepayments and other current assets		0		0
Total current assets		3,000,000		1,000,000
Net property, plant and equipment		67,000,000		59,000,000
Investment in consolidated subsidiaries		443,000,000		460,000,000
Equity investments in affiliates		268,000,000		233,000,000
Intangible assets, net		11,000,000		12,000,000
Derivative Instruments and Hedges, Noncurrent				0
Other non-current assets		0		0
Other Assets		722,000,000		705,000,000
Total Assets		792,000,000		765,000,000
Current portion of long-term debt — external		0		0
Accounts payable — trade		0		0
Accounts payable — affiliate		1,000,000		0
Derivative instruments		0		0
Accrued expenses and other current liabilities		0
Current Liabilities		1,000,000		0
Other Liabilities
Long-term debt — external		0		0
Long-term debt — affiliate		0		0
Derivative instruments		0		0
Other non-current liabilities		2,000,000		2,000,000
Total non-current liabilities		2,000,000		2,000,000
Total Liabilities		3,000,000		2,000,000
Contributed capital		797,000,000		822,000,000
Retained earnings		(8,000,000)		(58,000,000)
Accumulated other comprehensive loss		0		(1,000,000)
Noncontrolling interest		0		0
Total Members' Equity		789,000,000		763,000,000
Total Liabilities and Members’ Equity		792,000,000		765,000,000
Non-Guarantor Subsidiaries [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		120,000,000		124,000,000	[1]
Restricted cash		157,000,000		168,000,000	[1]
Accounts receivable — trade		138,000,000		93,000,000	[1]
Accounts receivable — affiliate	[1]			0
Inventory		39,000,000		39,000,000	[1]
Notes receivable		3,000,000		13,000,000	[1]
Prepayments and other current assets		29,000,000		18,000,000	[1]
Total current assets		486,000,000		455,000,000	[1]
Net property, plant and equipment		5,239,000,000		5,351,000,000	[1]
Investment in consolidated subsidiaries		0		0	[1]
Equity investments in affiliates		544,000,000		577,000,000	[1]
Intangible assets, net		1,166,000,000		1,216,000,000	[1]
Derivative Instruments and Hedges, Noncurrent	[1]			1,000,000
Other non-current assets		89,000,000		62,000,000	[1]
Other Assets		1,831,000,000		1,856,000,000	[1]
Total Assets		7,556,000,000		7,662,000,000	[1]
Current portion of long-term debt — external		309,000,000		339,000,000	[1]
Accounts payable — trade		67,000,000		46,000,000	[1]
Accounts payable — affiliate		10,000,000		33,000,000	[1]
Derivative instruments		5,000,000		18,000,000	[1]
Accrued expenses and other current liabilities		80,000,000		62,000,000	[1]
Current Liabilities		471,000,000		498,000,000	[1]
Other Liabilities
Long-term debt — external		4,047,000,000		4,153,000,000	[1]
Long-term debt — affiliate		0		0	[1]
Derivative instruments		9,000,000		31,000,000	[1]
Other non-current liabilities		87,000,000		85,000,000	[1]
Total non-current liabilities		4,143,000,000		4,269,000,000	[1]
Total Liabilities		4,614,000,000		4,767,000,000	[1]
Contributed capital		2,732,000,000		2,934,000,000	[1]
Retained earnings		144,000,000		(25,000,000)	[1]
Accumulated other comprehensive loss		(41,000,000)		(71,000,000)	[1]
Noncontrolling interest		107,000,000		57,000,000	[1]
Total Members' Equity		2,942,000,000		2,895,000,000	[1]
Total Liabilities and Members’ Equity		7,556,000,000		7,662,000,000	[1]
NRG Yield LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		111,000,000		22,000,000	[1]
Restricted cash		0		0	[1]
Accounts receivable — trade		0		0	[1]
Accounts receivable — affiliate	[1]			1,000,000
Inventory		0		0	[1]
Notes receivable		0		0	[1]
Prepayments and other current assets		0		0	[1]
Total current assets		111,000,000		23,000,000	[1]
Net property, plant and equipment				0	[1]
Investment in consolidated subsidiaries		1,969,000,000		1,844,000,000	[1]
Equity investments in affiliates		0		0	[1]
Intangible assets, net		0		0	[1]
Derivative Instruments and Hedges, Noncurrent	[1]			0
Other non-current assets		0		0	[1]
Other Assets		1,969,000,000		1,844,000,000	[1]
Total Assets		2,080,000,000		1,867,000,000	[1]
Current portion of long-term debt — external		0		0	[1]
Accounts payable — trade		0		0	[1]
Accounts payable — affiliate		0		0	[1]
Derivative instruments		0		0	[1]
Accrued expenses and other current liabilities		0		0	[1]
Current Liabilities		0		0	[1]
Other Liabilities
Long-term debt — external		0		0	[1]
Long-term debt — affiliate		0		0	[1]
Derivative instruments		0		0	[1]
Other non-current liabilities		0		0	[1]
Total non-current liabilities		0		0	[1]
Total Liabilities		0		0	[1]
Contributed capital		1,937,000,000		1,919,000,000	[1]
Retained earnings		177,000,000		16,000,000	[1]
Accumulated other comprehensive loss		(34,000,000)		(68,000,000)	[1]
Noncontrolling interest		0		0	[1]
Total Members' Equity		2,080,000,000		1,867,000,000	[1]
Total Liabilities and Members’ Equity		2,080,000,000		1,867,000,000
NRG Yield Operating LLC [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		0		0	[1]
Restricted cash		0		0	[1]
Accounts receivable — trade		0		1,000,000	[1]
Accounts receivable — affiliate	[1]			0
Inventory		0		0	[1]
Notes receivable		0		0	[1]
Prepayments and other current assets		2,000,000		1,000,000	[1]
Total current assets		2,000,000		2,000,000	[1]
Net property, plant and equipment				0	[1]
Investment in consolidated subsidiaries		3,288,000,000		3,198,000,000	[1]
Equity investments in affiliates		370,000,000		368,000,000	[1]
Intangible assets, net		0		0	[1]
Derivative Instruments and Hedges, Noncurrent	[1]			0
Other non-current assets		3,000,000		0	[1]
Other Assets		3,661,000,000		3,566,000,000	[1]
Total Assets		3,663,000,000		3,568,000,000	[1]
Current portion of long-term debt — external		0		0	[1]
Accounts payable — trade		23,000,000		0	[1]
Accounts payable — affiliate		11,000,000		16,000,000	[1]
Derivative instruments		0		0	[1]
Accrued expenses and other current liabilities		15,000,000		25,000,000	[1]
Current Liabilities		608,000,000		41,000,000	[1]
Other Liabilities
Long-term debt — external		841,000,000		896,000,000	[1]
Long-term debt — affiliate		44,000,000		618,000,000	[1]
Derivative instruments		0		0	[1]
Other non-current liabilities		8,000,000		7,000,000	[1]
Total non-current liabilities		893,000,000		1,521,000,000	[1]
Total Liabilities		1,501,000,000		1,562,000,000	[1]
Contributed capital		2,119,000,000		2,119,000,000	[1]
Retained earnings		(116,000,000)		(207,000,000)	[1]
Accumulated other comprehensive loss		(34,000,000)		(68,000,000)	[1]
Noncontrolling interest		193,000,000		162,000,000	[1]
Total Members' Equity		2,162,000,000		2,006,000,000	[1]
Total Liabilities and Members’ Equity		3,663,000,000		3,568,000,000	[1]
Consolidation, Eliminations [Member]
Condensed Balance Sheet Statements, Captions [Line Items]
Cash and cash equivalents		0	[2]	0	[3]
Restricted cash		0	[2]	0	[3]
Accounts receivable — trade		0	[2]	0	[3]
Accounts receivable — affiliate	[3]			0
Inventory		0	[2]	0	[3]
Notes receivable		0	[2]	0	[3]
Prepayments and other current assets		0	[2]	0	[3]
Total current assets		0	[2]	0	[3]
Net property, plant and equipment			[2]	0	[3]
Investment in consolidated subsidiaries		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Equity investments in affiliates		0	[2]	0	[3]
Intangible assets, net		0	[2]	0	[3]
Derivative Instruments and Hedges, Noncurrent	[3]			0
Other non-current assets		0	[2]	0	[3]
Other Assets		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Total Assets		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Current portion of long-term debt — external		0	[2]	0	[3]
Accounts payable — trade		0	[2]	0	[3]
Accounts payable — affiliate		0	[2]	0	[3]
Derivative instruments		0	[2]	0	[3]
Accrued expenses and other current liabilities		0	[2]	0	[3]
Current Liabilities		0	[2]	0	[3]
Other Liabilities
Long-term debt — external		0	[2]	0	[3]
Long-term debt — affiliate		0	[2]	0	[3]
Derivative instruments		0	[2]	0	[3]
Other non-current liabilities		0	[2]	0	[3]
Total non-current liabilities		0	[2]	0	[3]
Total Liabilities		0	[2]	0	[3]
Contributed capital		(5,648,000,000)	[2]	(5,875,000,000)	[3]
Retained earnings		(20,000,000)	[2]	290,000,000	[3]
Accumulated other comprehensive loss		75,000,000	[2]	140,000,000	[3]
Noncontrolling interest		(107,000,000)	[2]	(57,000,000)	[3]
Total Members' Equity		(5,700,000,000)	[2]	(5,502,000,000)	[3]
Total Liabilities and Members’ Equity		$ (5,700,000,000)	[2]	$ (5,502,000,000)	[3]
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.
[2]	(a) All significant intercompany transactions have been eliminated in consolidation.
[3]	(b) All significant intercompany transactions have been eliminated in consolidation.

Condensed Consolidating Fina_10

Condensed Consolidating Financial Information PP Cash Flows (Details) - USD ($) $ in Millions		9 Months Ended
		Sep. 30, 2018	Sep. 30, 2017
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets		$ 126	$ 176	[1]
Net Cash Provided by (Used in) Operating Activities		397	374	[1]
Net contributions from noncontrolling interests	[1]		13
Intercompany transactions between Clearway Energy LLC and subsidiaries		0	0	[1]
Capital expenditures		(62)	(102)	[1]
Cash receipts from notes receivable		10	11	[1]
Return of investment from unconsolidated affiliates		22	32	[1]
Investments in unconsolidated affiliates		(16)	(48)	[1]
Net Cash Provided by (Used in) Investing Activities		(175)	(283)	[1]
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets		0	(26)	[1]
Net proceeds from the issuance of Class C units		151	33	[1]
Transfer of funds under intercompany cash management arrangement		0	0	[1]
Payments of distributions, net of contributions		(189)	(149)	[1]
Proceeds from the issuance of long-term debt — external		227	130	[1]
Payments of debt issuance costs		(5)	(12)	[1]
Proceeds from the revolving credit facility		35	0	[1]
Payments for long-term debt — external		(369)	(255)	[1]
Net Cash (Used in) Provided by Financing Activities		(148)	(266)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash		74	(175)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		314	497	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period		388	322	[1]
Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets		0
Net Cash Provided by (Used in) Operating Activities		9	34
Net contributions from noncontrolling interests			0
Intercompany transactions between Clearway Energy LLC and subsidiaries		0	0
Capital expenditures		0	0
Cash receipts from notes receivable		0	0
Return of investment from unconsolidated affiliates		7	7
Investments in unconsolidated affiliates		(16)	(41)
Net Cash Provided by (Used in) Investing Activities		(9)	(34)
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets			(25)
Net proceeds from the issuance of Class C units		0	0
Transfer of funds under intercompany cash management arrangement		0	(1)
Proceeds from the issuance of long-term debt — external		0	0
Payments of debt issuance costs		0	0
Proceeds from the revolving credit facility		0
Payments for long-term debt — external		0	(30)
Net Cash (Used in) Provided by Financing Activities		0	(6)
Net Decrease in Cash, Cash Equivalents and Restricted Cash		0	(6)
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		0	9
Cash, Cash Equivalents and Restricted Cash at End of Period		0	3
Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets		0
Net Cash Provided by (Used in) Operating Activities		429	417	[1]
Net contributions from noncontrolling interests	[1]		0
Intercompany transactions between Clearway Energy LLC and subsidiaries		0	0	[1]
Capital expenditures		(62)	(102)	[1]
Cash receipts from notes receivable		10	11	[1]
Return of investment from unconsolidated affiliates		11	9	[1]
Investments in unconsolidated affiliates		0	(7)	[1]
Net Cash Provided by (Used in) Investing Activities		(33)	(89)	[1]
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets	[1]		(44)
Net proceeds from the issuance of Class C units		0	0	[1]
Transfer of funds under intercompany cash management arrangement		(3)	0	[1]
Proceeds from the issuance of long-term debt — external		227	130	[1]
Payments of debt issuance costs		(2)	(12)	[1]
Proceeds from the revolving credit facility		0
Payments for long-term debt — external		(369)	(225)	[1]
Net Cash (Used in) Provided by Financing Activities		(411)	(362)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash		(15)	(34)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		292	277	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period		277	243	[1]
NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets		0
Net Cash Provided by (Used in) Operating Activities		0	0	[1]
Net contributions from noncontrolling interests	[1]		0
Intercompany transactions between Clearway Energy LLC and subsidiaries		108	(13)	[1]
Capital expenditures		0	0	[1]
Cash receipts from notes receivable		0	0	[1]
Return of investment from unconsolidated affiliates		0	0	[1]
Investments in unconsolidated affiliates		0	0	[1]
Net Cash Provided by (Used in) Investing Activities		108	(13)	[1]
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets	[1]		0
Net proceeds from the issuance of Class C units		151	33	[1]
Transfer of funds under intercompany cash management arrangement		4	(6)	[1]
Proceeds from the issuance of long-term debt — external		0	0	[1]
Payments of debt issuance costs		0	0	[1]
Proceeds from the revolving credit facility		0
Payments for long-term debt — external		0	0	[1]
Net Cash (Used in) Provided by Financing Activities		(19)	(122)	[1]
Net Decrease in Cash, Cash Equivalents and Restricted Cash		89	(135)	[1]
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		22	211	[1]
Cash, Cash Equivalents and Restricted Cash at End of Period		111	76	[1]
NRG Yield Operating LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets		126	176
Net Cash Provided by (Used in) Operating Activities		(41)	(77)
Net contributions from noncontrolling interests			13
Intercompany transactions between Clearway Energy LLC and subsidiaries		(108)	13
Capital expenditures		0	0
Cash receipts from notes receivable		0	0
Return of investment from unconsolidated affiliates		4	16
Investments in unconsolidated affiliates		0	0
Net Cash Provided by (Used in) Investing Activities		(241)	(147)
Net distributions and return of capital to NRG prior to the acquisition of Drop Down Assets			(7)
Net proceeds from the issuance of Class C units		0
Transfer of funds under intercompany cash management arrangement		(1)	7
Proceeds from the issuance of long-term debt — external		0	0
Payments of debt issuance costs		(3)	0
Proceeds from the revolving credit facility		35
Payments for long-term debt — external		0	0
Net Cash (Used in) Provided by Financing Activities		282	224
Net Decrease in Cash, Cash Equivalents and Restricted Cash		0	0
Cash, Cash Equivalents and Restricted Cash at Beginning of Period		0	0
Cash, Cash Equivalents and Restricted Cash at End of Period		$ 0	0
Drop Down Assets [Member] | Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets			0
Drop Down Assets [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets	[1]		0
Drop Down Assets [Member] | NRG Yield LLC [Member]
Condensed Cash Flow Statements, Captions [Line Items]
Payments for the Drop Down Assets	[1]		$ 0
[1]	(a) Retrospectively adjusted as discussed in Note 1, Nature of Business.