Clearway Energy (CWEN) 10-K 28 Feb 17 2016 FY Annual report Financial data

Document and Entity Information

Document and Entity Information - USD ($)	12 Months Ended
	Dec. 31, 2016	Jan. 31, 2017	Jun. 30, 2016
Document And Entity Information [Abstract]
Entity Registrant Name	NRG Yield, Inc.
Entity Central Index Key	1,567,683
Document Type	10-K
Document Period End Date	Dec. 31, 2016
Amendment Flag	false
Current Fiscal Year End Date	--12-31
Entity Current Reporting Status	Yes
Entity Filer Category	Large Accelerated Filer
Entity Voluntary Filers	No
Entity Well-known Seasoned Issuer	Yes
Entity Public Float			$ 1,502,686,604
Document Fiscal Year Focus	2,016
Document Fiscal Period Focus	FY
Common Class A [Member]
Class of Stock
Entity Common Stock, Shares Outstanding		34,586,250
Common Class B [Member]
Class of Stock
Entity Common Stock, Shares Outstanding		42,738,750
Common Class C [Member]
Class of Stock
Entity Common Stock, Shares Outstanding		62,789,804
Common Class D [Member]
Class of Stock
Entity Common Stock, Shares Outstanding		42,738,750

Consolidated Statements of Oper

Consolidated Statements of Operations - USD ($) shares in Millions, $ in Millions		3 Months Ended				12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Revenues
Total operating revenues		$ 232	$ 272	$ 283	$ 234	$ 1,021	$ 953	$ 828
Operating Costs and Expenses
Cost of operations						306	321	277
Depreciation and amortization						297	297	233
Impairment losses						183	0	0
General and administrative						16	12	8
Acquisition-related transaction and integration costs						1	3	4
Total operating costs and expenses						803	633	522
Operating Income		(99)	117	128	72	218	320	306
Other Income (Expense)
Equity in earnings of unconsolidated affiliates						37	26	17
Other income, net						3	3	6
Gains (Losses) on Extinguishment of Debt						0	(9)	(1)
Interest expense						(274)	(263)	(216)
Total other expense, net						(234)	(243)	(194)
Income Before Income Taxes						(16)	77	112
Income tax (benefit) expense						(1)	12	4
Net Income		(126)	47	63	1	(15)	65	108
Less: Pre-acquisition net income (loss) of Drop Down Assets						10	(10)	44
Net (Loss) Income Excluding Pre-acquisition Net Income (Loss) of Drop Down Assets						(25)	75	64
Less: Net (loss) income attributable to noncontrolling interests						(82)	42	48
Net income attributable to NRG Yield, Inc.		$ (13)	$ 33	$ 32	$ 5	57	33	16
Earnings Per Share Attributable to NRG Yield, Inc. Class A and Class C Common Stockholders
Earnings Per Share, Basic		$ (0.14)	$ 0.34	$ 0.33	$ 0.05
Dividends Per Class A Common Share		$ 0.25	$ 0.24	$ 0.23
Noncontrolling Interest [Member]
Other Income (Expense)
Less: Pre-acquisition net income (loss) of Drop Down Assets						10	(10)	44
Net (Loss) Income Excluding Pre-acquisition Net Income (Loss) of Drop Down Assets						(82)	42	$ 48
Common Class A [Member]
Other Income (Expense)
Net income attributable to NRG Yield, Inc.						$ 20	$ 14
Earnings Per Share Attributable to NRG Yield, Inc. Class A and Class C Common Stockholders
Weighted average number of common shares outstanding — basic and diluted						35	35	28
Weighted Average Number of Shares Outstanding, Diluted		35	49	49	35
Weighted Average Number of Shares Outstanding, Basic		35	35	35	35
Earnings per weighted average common share — basic and diluted	[1]					$ 0.58	$ 0.40	$ 0.30
Earnings Per Share, Diluted		$ (0.14)	$ 0.30	$ 0.29	$ 0.05
Dividends Per Class A Common Share					$ 0.225	$ 0.945	$ 1.015	$ 1.42
Common Class C [Member]
Other Income (Expense)
Net income attributable to NRG Yield, Inc.						$ 37	$ 19
Earnings Per Share Attributable to NRG Yield, Inc. Class A and Class C Common Stockholders
Weighted average number of common shares outstanding — basic and diluted						63	49	28
Weighted Average Number of Shares Outstanding, Diluted		63	73	73	63
Weighted Average Number of Shares Outstanding, Basic		63	63	63	63
Earnings Per Share, Basic	[1]					$ 0.58	$ 0.40
Earnings Per Share, Diluted		$ (0.14)	$ 0.32	$ 0.31	$ 0.05
Dividends Per Class A Common Share						$ 0.945	$ 0.625
[1]	Net income attributable to NRG Yield, Inc. and basic and diluted earnings per share might not recalculate due to presenting values in millions rather than whole dollars.

Consolidated Statements of Comp

Consolidated Statements of Comprehensive Income - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Other Comprehensive Income (Loss), net of tax
Net Income	$ (15)	$ 65	$ 108
Unrealized gain (loss) on derivatives, net of income tax benefit of $0, $10, and $5	0	(21)	(74)
Mark-to-market of cash flow hedge accounting contracts	13	(7)	(60)
Other comprehensive income (loss)	13	(7)	(60)
Comprehensive (Loss) Income	(2)	58	48
Less: Pre-acquisition net income (loss) of Drop Down Assets	10	(10)	44
Less: Comprehensive (loss) income attributable to noncontrolling interests	(68)	53	(3)
Comprehensive Income Attributable to NRG Yield, Inc.	$ 56	$ 15	$ 7

Consolidated Statements of Com4

Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Statement of Comprehensive Income [Abstract]
Unrealized gain/loss on derivatives, income tax benefit/(expense)	$ 0	$ 10	$ 5

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Current Assets
Cash and cash equivalents	$ 317	$ 111
Restricted cash	164	131
Accounts receivable — trade	91	101
Inventory	39	36
Derivative instruments	2	0
Notes receivable — current	16	17
Prepayments and other current assets	16	20
Total current assets	645	416
Property, plant and equipment
Under construction	25	9
Total property, plant and equipment	6,411	6,660
Less accumulated depreciation	(951)	(782)
Property, plant and equipment, net	5,460	5,878
Other Assets
Equity investments in affiliates	710	697
Notes receivable — non-current	14	30
Intangible assets, net	1,286	1,362
Derivative instruments	1	0
Deferred income taxes	216	170
Other non-current assets	51	136
Total other assets	2,278	2,395
Total Assets	8,383	8,689
Current Liabilities
Current portion of long-term debt	282	264
Accounts payable	23	23
Accounts payable — affiliate	40	86
Derivative instruments	29	39
Accrued expenses and other current liabilities	85	77
Total current liabilities	459	489
Other Liabilities
Long-term debt	5,426	5,329
Due to Related Parties, Noncurrent	9	0
Derivative instruments	43	61
Other non-current liabilities	76	72
Total non-current liabilities	5,554	5,462
Total Liabilities	6,013	5,951
Stockholders' Equity
Preferred stock, $0.01 par value; 10,000,000 shares authorized; none issued	0	0
Common Stock, Value, Issued	1	1
Additional Paid in Capital	1,879	1,855
(Accumulated deficit) Retained earnings	(2)	12
Accumulated other comprehensive loss	(28)	(27)
Noncontrolling interest	520	897
Total Stockholders' Equity	2,370	2,738
Total Liabilities and Stockholders’ Equity	$ 8,383	$ 8,689

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - $ / shares	Dec. 31, 2016	Dec. 31, 2015	Jul. 22, 2013
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Common Class A [Member]
Common Stock, Par or Stated Value Per Share	$ 0.01
Common Stock, Shares Authorized			500,000,000
Common Class B [Member]
Common Stock, Shares Authorized			500,000,000

Consolidated Statements Of Cas

Consolidated Statements Of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Cash Flows from Operating Activities
Net Income	$ (15)	$ 65	$ 108
Adjustments to reconcile net income to net cash provided by operating activities:
Equity in earnings of unconsolidated affiliates	37	26	17
Distributions from unconsolidated affiliates	49	43	21
Depreciation, amortization and ARO accretion	300	299	235
Amortization of financing costs and debt discounts	20	16	11
Amortization of intangibles and out-of-market contracts	75	54	28
Loss on debt extinguishment	0	9	1
Change in deferred income taxes	(1)	12	4
Impairment losses	183	0	0
Changes in derivative instruments	(19)	(43)	(12)
Loss on disposal of asset components	(6)	(3)	0
Changes in prepaid and accrued capacity payments	8	12	0
Changes in other working capital	7	(15)	(17)
Net Cash Provided by Operating Activities	560	405	362
Cash Flows from Investing Activities
Acquisition of businesses, net of cash acquired	0	(37)	(901)
Acquisition of Drop Down Assets, net of cash acquired	77	698	311
Capital expenditures	(20)	(29)	(60)
Receipt of indemnity from supplier	0	0	57
(Increase) decrease in restricted cash	(33)	(1)	25
Cash receipts from notes receivable	(17)	(17)	(14)
Proceeds from renewable energy grants	0	0	422
Return of investment from unconsolidated affiliates	28	42	4
Investments in unconsolidated affiliates	(80)	(402)	0
Other	4	0	11
Net Cash Used in Investing Activities	(161)	(1,108)	(739)
Cash Flows from Financing Activities
Contributions from tax equity investors, net of distributions	5	122	190
Capital contributions from NRG	0	0	2
Distributions and return of capital to NRG prior to the acquisition of Drop Down Assets	(113)	(59)	(335)
Proceeds from the issuance of common stock	0	599	630
Payments of dividends and distributions	(183)	(139)	(101)
Proceeds from the revolving credit facility	60	551	500
Payments for the revolving credit facility	(366)	(245)	0
Proceeds from issuance of long-term debt	675	293	523
Payments of debt issuance costs	(7)	(13)	(36)
Payments for long-term debt	(264)	(724)	(626)
Net Cash Provided by Financing Activities	(193)	385	747
Net Increase (Decrease) in Cash and Cash Equivalents	206	(318)	370
Cash and Cash Equivalents at Beginning of Period	111	429	59
Cash and Cash Equivalents at End of Period	317	111	429
Interest paid, net of amount capitalized	(266)	(274)	(192)
Additions (reductions) to fixed assets for accrued capital expenditures	3	1	(21)
Decrease to fixed assets for accrued grants	0	0	34
Decrease to fixed assets for deferred tax asset	0	(19)	7
Non-cash adjustment for change in tax basis of assets	44	38	(14)
Increase in debt due to accrued interest converted to debt	0	0	11
Non-cash return of capital and distributions to NRG, net of contributions	$ 43	$ 13	$ (1,058)

Consolidated Statements of Stoc

Consolidated Statements of Stockholders Equity - USD ($)	Total	Preferred Stock [Member]	Common Stock	Additional Paid-in Capital [Member]	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest [Member]
Statement of Stockholders' Equity
Total Stockholders' Equity	$ 1,588,000,000	$ 0	$ 0	$ 621,000,000	$ 8,000,000	$ 0	$ 959,000,000
Net Income Excluding Pre-acquisition Net (Loss) Income of Drop Down Assets	64,000,000	0	0	0	16,000,000	0	48,000,000
Less: Pre-acquisition net income (loss) of Drop Down Assets	44,000,000	0	0	0	0	0	44,000,000
Unrealized gain/(loss) on derivatives	(60,000,000)	0	0	0	0	(9,000,000)	(51,000,000)
Gross Payment to Acquire Business under Common Control	(357,000,000)	0	0	0	0	0	(357,000,000)
Payment to Acquire Business under Common Control	(311,000,000)
Contributions from tax equity investors, net of distributions	190,000,000	0	0	0	0	0	190,000,000
Non-cash return of capital and distributions to NRG, net of contributions	1,058,000,000	0	0	0	0	0	1,058,000,000
Payment of capital distributions and returns of capital, net of capital contributions	(333,000,000)	0	0	0	0	0	(333,000,000)
Proceeds from the issuance of common stock	630,000,000	0	0	630,000,000	0	0	0
Non-cash adjustment for change in tax basis of assets	(14,000,000)	0	0	(14,000,000)	0	0	0
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt	23,000,000	0	0	23,000,000	0	0	0
Payments of Ordinary Dividends, Common Stock	(101,000,000)	0	0	(20,000,000)	(21,000,000)	0	(60,000,000)
Total Stockholders' Equity	2,732,000,000	0	0	1,240,000,000	3,000,000	(9,000,000)	1,498,000,000
Net Income Excluding Pre-acquisition Net (Loss) Income of Drop Down Assets	75,000,000	0	0	0	33,000,000	0	42,000,000
Less: Pre-acquisition net income (loss) of Drop Down Assets	(10,000,000)	0	0	0	0	0	(10,000,000)
Unrealized gain/(loss) on derivatives	(7,000,000)	0	0	0	0	(18,000,000)	11,000,000
Payment to Acquire Business under Common Control	(698,000,000)	0	0	0	0	0	(698,000,000)
Contributions from tax equity investors, net of distributions	122,000,000	0	0	0	0	0	122,000,000
Noncontrolling Interest, Increase from Business Combination	74,000,000	0	0	0	0	0	74,000,000
Non-cash return of capital and distributions to NRG, net of contributions	(13,000,000)	0	0	0	0	0	(13,000,000)
Payment of capital distributions and returns of capital, net of capital contributions	(59,000,000)	0	0	0	0	0	(59,000,000)
Share-based Compensation	1,000,000	0	0	1,000,000	0	0	0
Proceeds from the issuance of common stock	599,000,000	0	1,000,000	598,000,000	0	0	0
Non-cash adjustment for change in tax basis of assets	38,000,000	0	0	38,000,000	0	0	0
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt	23,000,000	0	0	23,000,000	0	0	0
Payments of Ordinary Dividends, Common Stock	(139,000,000)	0	0	(45,000,000)	(24,000,000)	0	(70,000,000)
Total Stockholders' Equity	2,738,000,000	0	1,000,000	1,855,000,000	12,000,000	(27,000,000)	897,000,000
Net Income Excluding Pre-acquisition Net (Loss) Income of Drop Down Assets	(25,000,000)	0	0	0	57,000,000	0	(82,000,000)
Less: Pre-acquisition net income (loss) of Drop Down Assets	10,000,000	0	0	0	0	0	10,000,000
Unrealized gain/(loss) on derivatives	13,000,000	0	0	0	0	(1,000,000)	14,000,000
Payment to Acquire Business under Common Control	(77,000,000)	0	0	0	0	0	(77,000,000)
Contributions from tax equity investors, net of distributions	5,000,000	0	0	0	0	0	5,000,000
Non-cash return of capital and distributions to NRG, net of contributions	(43,000,000)	0	0	0	0	0	(43,000,000)
Payment of capital distributions and returns of capital, net of capital contributions	(123,000,000)	0	0	0	0	0	(123,000,000)
Share-based Compensation	1,000,000	0	0	1,000,000	0	0	0
Proceeds from the issuance of common stock	0
Non-cash adjustment for change in tax basis of assets	44,000,000	0	0	44,000,000	0	0	0
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt	23,000,000
Payments of Ordinary Dividends, Common Stock	(173,000,000)	0	0	(21,000,000)	(71,000,000)	0	(81,000,000)
Total Stockholders' Equity	$ 2,370,000,000	$ 0	$ 1,000,000	$ 1,879,000,000	$ (2,000,000)	$ (28,000,000)	$ 520,000,000

Schedule 1 - Yield, Inc,'s Fina

Schedule 1 - Yield, Inc,'s Financial Statements NRG Yield PL - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating Expenses	$ 306	$ 321	$ 277
Interest Expense	(274)	(263)	(216)
Total other expense, net	(234)	(243)	(194)
Income Before Income Taxes	(16)	77	112
Net Income	(15)	65	108
Income tax (benefit) expense	(1)	12	4
Less: Net (loss) income attributable to noncontrolling interests	(82)	42	48
Less: Pre-acquisition net income (loss) of Drop Down Assets	10	(10)	44
Net income attributable to NRG Yield, Inc.	57	33	16
NRG Yield, Inc. [Member]
Operating Expenses	2	2	0
Equity in Earnings of Consolidated Subsidiaries	(2)	88	117
Interest Expense	(12)	(9)	(5)
Total other expense, net	(14)	79	112
Income Before Income Taxes	(16)	77	112
Net Income	(15)	65	108
Income tax (benefit) expense	(1)	12	4
Less: Net (loss) income attributable to noncontrolling interests	(82)	42	48
Less: Pre-acquisition net income (loss) of Drop Down Assets	10	(10)	44
Net income attributable to NRG Yield, Inc.	$ 57	$ 33	$ 16

Schedule 1 - Yield, Inc,'s Fi10

Schedule 1 - Yield, Inc,'s Financial Statements NRG Yield BS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Less: Pre-acquisition net income of Acquired ROFO assets	$ 10,000	$ (10,000)
Income Before Income Taxes	(16,000)	77,000
Cash and cash equivalents	317,000	111,000
Deferred Tax Assets, Gross	216,000	170,000
Total Assets	8,383,000	8,689,000
Long-term Debt	5,770,000	5,656,000
Total Liabilities	6,013,000	5,951,000
Preferred stock, $0.01 par value; 10,000,000 shares authorized; none issued	0	0
Common Stock, Value, Issued	1,000	1,000
Additional Paid in Capital	1,879,000	1,855,000
(Accumulated deficit) Retained earnings	(2,000)	12,000
Accumulated other comprehensive loss	(28,000)	(27,000)
Noncontrolling interest	520,000	897,000
Total Stockholders' Equity	2,370,000	2,738,000
Total Liabilities and Stockholders’ Equity	$ 8,383,000	$ 8,689,000
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
Common Class A [Member]
Common Stock, Par or Stated Value Per Share	$ 0.01
NRG Yield, Inc. [Member]
Less: Pre-acquisition net income of Acquired ROFO assets	$ 10,000	$ (10,000)
Income Before Income Taxes	(16,000)	77,000
Cash and cash equivalents	1,000	1,000
Investments in subsidiaries	2,135,000	2,540,000
Notes Receivable, Related Parties	618,000	618,000
Deferred Tax Assets, Gross	216,000	170,000
Total Assets	2,970,000	3,329,000
Deferred income taxes	0	4,000
Other Liabilities, Current	2,000	1,000
Long-term Debt	598,000	586,000
Total Liabilities	600,000	591,000
Preferred stock, $0.01 par value; 10,000,000 shares authorized; none issued	0	0
Common Stock, Value, Issued	1,000	1,000
Additional Paid in Capital	1,879,000	1,855,000
(Accumulated deficit) Retained earnings	(2,000)	12,000
Accumulated other comprehensive loss	(28,000)	(27,000)
Noncontrolling interest	520,000	897,000
Total Stockholders' Equity	2,370,000	2,738,000
Total Liabilities and Stockholders’ Equity	$ 2,970,000	$ 3,329,000
Preferred Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Preferred Stock, Shares Authorized	10,000,000	10,000,000
Preferred Stock, Shares Issued	0	0
NRG Yield, Inc. [Member] | Common Class A [Member]
Common Stock, Par or Stated Value Per Share	$ 0.01	$ 0.01
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Shares, Issued	34,586,250	34,586,250
NRG Yield, Inc. [Member] | Common Class B [Member]
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Shares, Issued	42,738,750	42,738,750
NRG Yield, Inc. [Member] | Common Class C [Member]
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Shares, Issued	62,784,250	34,586,250
NRG Yield, Inc. [Member] | Common Class D [Member]
Common Stock, Shares Authorized	500,000,000	500,000,000
Common Stock, Shares, Issued	42,738,750	42,738,750
NRG Yield [Member]
Cash and cash equivalents	$ 1,000	$ 1,000

Schedule 1 - Yield, Inc,'s Fi11

Schedule 1 - Yield, Inc,'s Financial Statements NRG Yield CF $ in Thousands	12 Months Ended
	Dec. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)
Operating Income	$ 218,000	$ 320,000	$ 306,000
Net Cash Provided by (Used in) Operating Activities	560,000	405,000	362,000
Proceeds from Issuance of Long-term Debt	675,000	293,000	523,000
Net Cash Used in Investing Activities	(161,000)	(1,108,000)	(739,000)
Proceeds from the issuance of common stock	0	599,000	630,000
Payments of Ordinary Dividends, Common Stock	(173,000)	(139,000)	(101,000)
Net Cash Provided by Financing Activities	(193,000)	385,000	747,000
Net Increase (Decrease) in Cash and Cash Equivalents	206,000	(318,000)	370,000
Cash and cash equivalents	317,000	111,000	429,000
NRG Yield [Member]
Net Cash Provided by (Used in) Operating Activities	(5,000)	2,000	(1,000)
Investment in consolidated subsidiaries	5,000	(600,000)	(630,000)
Proceeds from Issuance of Long-term Debt	0	288,000	345,000
Increase (Decrease) in Notes Receivable, Related Parties	0	(281,000)	(337,000)
Net Cash Used in Investing Activities	5,000	(881,000)	(967,000)
Proceeds from the issuance of common stock	0	599,000	630,000
Payments of Financing Costs	0	(7,000)	(7,000)
Proceeds from Contributions from Affiliates	92,000	69,000	41,000
Payments of Ordinary Dividends, Common Stock	(92,000)	(69,000)	(41,000)
Net Cash Provided by Financing Activities	0	880,000	968,000
Net Increase (Decrease) in Cash and Cash Equivalents	0	1,000	0
Cash and cash equivalents	$ 1,000	$ 1,000	$ 0

Schedule 1 - Yield, Inc,'s Fi12

Schedule 1 - Yield, Inc,'s Financial Statements Footnotes - USD ($) $ in Millions	Jun. 29, 2015	Jul. 29, 2014	Jul. 22, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Nature of Business [Line Items]
Payments of Capital Distribution				$ 113	$ 59	$ 335
Proceeds from the issuance of common stock			$ 468	0	599	630
NRG Yield [Member]
Nature of Business [Line Items]
Proceeds from the issuance of common stock				0	599	630
Common Class C [Member]
Nature of Business [Line Items]
Proceeds from the issuance of common stock	$ 599
NRG Yield LLC [Member] | NRG Yield, Inc. [Member]
Nature of Business [Line Items]
Payments of Capital Distribution				$ 92	$ 69	$ 41
Public Shareholders [Member] | Common Class A [Member]
Nature of Business [Line Items]
Sale of Stock, Number of Shares Issued in Transaction		12,075,000	22,511,250
Proceeds from the issuance of common stock		$ 630
NRG Yield [Member] | NRG Yield [Member]
Nature of Business [Line Items]
Sale of Stock, Number of Shares Issued in Transaction	28,198,000

Nature of Business

Nature of Business	12 Months Ended
	Dec. 31, 2016
Nature of Business Disclosure [Abstract]
Nature of Business	Nature of Business The Company was formed by NRG as a Delaware corporation on December 20, 2012 and closed its initial public offering on July 22, 2013. In connection with its initial public offering, the Company's shares of Class A common stock began trading on the New York Stock Exchange under the symbol “NYLD.” Effective May 14, 2015, the Company completed a stock split in connection with which each outstanding share of Class A common stock was split into one share of Class A common stock and one share of Class C common stock, and each outstanding share of Class B common stock was split into one share of Class B common stock and one share of Class D common stock. The stock split is referred to as the Recapitalization and all references to share or per share amounts in the accompanying consolidated financial statements and applicable disclosures have been retrospectively adjusted to reflect the Recapitalization. Following the Recapitalization, the Company's Class A common stock continued trading on the New York Stock Exchange under the new ticker symbol "NYLD.A" and the Class C common stock began trading under the ticker symbol "NYLD." NRG, through its holdings of Class B common stock and Class D common stock, has a 55.1% voting interest in the Company and receives distributions from NRG Yield LLC through its ownership of Class B units and Class D units. The holders of the Company's issued and outstanding shares of Class A common stock and Class C common stock are entitled to dividends as declared and have 44.9% of the voting power in the Company. The Company is the sole managing member of NRG Yield LLC and operates and controls all of its business and affairs and consolidates the financial results of NRG Yield LLC and its subsidiaries. NRG Yield LLC is a holding company for the companies that directly and indirectly own and operate the Company's business. As of December 31, 2016 , the Company and NRG have 53.3% and 46.7% economic interests in NRG Yield LLC, respectively. As a result of the current ownership of the Class B common stock and Class D common stock, NRG continues at the present time to control the Company, and the Company in turn, as the sole managing member of NRG Yield LLC, controls NRG Yield LLC and its subsidiaries. The following table represents the structure of the Company as of December 31, 2016 : As of December 31, 2016 , 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 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 CVSR 100 % 250 Pacific Gas and Electric 2038 Desert Sunlight 250 25 % 63 Southern California Edison 2035 Desert Sunlight 300 25 % 75 Pacific Gas and Electric 2040 Kansas South 100 % 20 Pacific Gas and Electric 2033 Roadrunner 100 % 20 El Paso Electric 2031 TA High Desert 100 % 20 Southern California Edison 2033 610 Distributed Solar AZ DG Solar Projects 100 % 5 Various 2025 - 2033 PFMG DG Solar Projects 51 % 4 Various 2032 9 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) 74.3 % 16 Corn Belt Power Cooperative 2027 Elbow Creek (b) 75 % 92 NRG Power Marketing LLC 2022 Elkhorn Ridge (b) 50.3 % 41 Nebraska Public Power District 2029 Forward (b) 75 % 22 Constellation NewEnergy, Inc. 2017 Goat Wind (b) 74.9 % 113 Dow Pipeline Company 2025 Hardin (b) 74.3 % 11 Interstate Power and Light Company 2027 Laredo Ridge 100 % 80 Nebraska Public Power District 2031 Lookout (b) 75 % 29 Southern Maryland Electric Cooperative 2030 Odin (b) 74.9 % 15 Missouri River Energy Services 2028 Pinnacle 100 % 55 Maryland Department of General Services and University System of Maryland 2031 San Juan Mesa (b) 56.3 % 68 Southwestern Public Service Company 2025 Sleeping Bear (b) 75 % 71 Public Service Company of Oklahoma 2032 South Trent 100 % 101 AEP Energy Partners 2029 Spanish Fork (b) 75 % 14 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 Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration Taloga 100 % 130 Oklahoma Gas & Electric 2031 Wildorado (b) 74.9 % 121 Southwestern Public Service Company 2027 1,999 Thermal Thermal equivalent MWt (c) 100 % 1,319 Various Various NRG Energy Center Dover LLC 100 % 103 NRG Power Marketing LLC 2018 Thermal generation 100 % 20 Various Various 1,442 Total net capacity (excluding equivalent MWt) (d) 4,686 (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 December 31, 2016 . (b) Projects are part of tax equity arrangements. (c) 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. (d) NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs. In addition to the facilities owned or leased in the table above, the Company 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 131 MW based on cash to be distributed. For further discussions, refer to Note 5 , Investments Accounted for by the Equity Method and Variable Interest Entities to the Consolidated Financial Statements. Substantially all of the Company's generation assets are under long-term contractual arrangements for the output or capacity from these assets. The thermal assets are comprised of district energy systems and combined heat and power plants that produce steam, hot water and/or chilled water and, in some instances, electricity at a central plant. Three out of the fourteen district energy systems are subject to rate regulation by state public utility commissions while the other district energy systems have rates determined by negotiated bilateral contracts. As described in Note 15 , Related Party Transactions , the Company has a management services agreement with NRG for various services, including human resources, accounting, tax, legal, information systems, treasury, and risk management. Stockholders' equity represents the equity associated with the Class A and Class C common stockholders, the equity associated with the Class B and Class D common stockholder, NRG, and the third-party interests under certain tax equity arrangements are classified as noncontrolling interest. During the years ending December 31, 2016 and 2015, the Company completed three acquisitions of Drop Down Assets from NRG. 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). For further discussion, see Note 3, Business Acquisitions.

Summary of Significant Accounti

Summary of Significant Accounting Policies	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Summary of Significant Accounting Policies	Summary of Significant Accounting Policies Basis of Presentation and Principles of Consolidation The Company's consolidated financial statements have been prepared in accordance with GAAP. The ASC is the source of authoritative GAAP to be applied by nongovernmental entities. In addition, the rules and interpretative releases of the SEC under authority of federal securities laws are also sources of authoritative GAAP for SEC registrants. The consolidated financial statements include the Company's accounts and operations and those of its subsidiaries in which it has a controlling interest. All significant intercompany transactions and balances have been eliminated in consolidation. The usual condition for a controlling financial interest is ownership of a majority of the voting interests of an entity. However, a controlling financial interest may also exist through arrangements that do not involve controlling voting interests. As such, the Company applies the guidance of ASC 810, Consolidations, or ASC 810, to determine when an entity that is insufficiently capitalized or not controlled through its voting interests, referred to as a variable interest entity, or VIE, should be consolidated. Cash and Cash Equivalents Cash and cash equivalents include highly liquid investments with an original maturity of three months or less at the time of purchase. Cash and cash equivalents held at project subsidiaries was $105 million and $93 million as of December 31, 2016 and 2015 , respectively. Restricted Cash Restricted cash consists primarily of funds held to satisfy the requirements of certain debt agreements and funds held within the Company's projects that are restricted in their use. Of these funds as of December 31, 2016 , approximately $25 million is designated for current debt service payments, $13 million is designated to fund operating expenses and $37 million is designated for distributions to the Company, with the remaining $90 million restricted for reserves including debt service, performance obligations and other reserves, as well as capital expenditures. Trade Receivables and Allowance for Doubtful Accounts Trade receivables are reported on the balance sheet at the invoiced amount adjusted for any write-offs and the allowance for doubtful accounts. The allowance for doubtful accounts is reviewed periodically based on amounts past due and significance. The allowance for doubtful accounts was immaterial as of December 31, 2016 and 2015 . Inventory Inventory consists principally of spare parts and fuel oil. Spare parts inventory is valued at weighted average cost, unless evidence indicates that the weighted average cost will not be recovered with a normal profit in the ordinary course of business. Fuel oil inventory is valued at the lower of weighted average cost or market. The Company removes fuel inventories as they are used in the production of steam, chilled water or electricity. Spare parts inventory are removed when they are used for repairs, maintenance or capital projects. Property, Plant and Equipment Property, plant and equipment are stated at cost or, in the case of third party business acquisitions, fair value; however impairment adjustments are recorded whenever events or changes in circumstances indicate that their carrying values may not be recoverable. See Note 3 , Business Acquisitions , for more information on acquired property, plant and equipment. Significant additions or improvements extending asset lives are capitalized as incurred, while repairs and maintenance that do not improve or extend the life of the respective asset are charged to expense as incurred. Depreciation is computed using the straight-line method over the estimated useful lives. Certain assets and their related accumulated depreciation amounts are adjusted for asset retirements and disposals with the resulting gain or loss included in cost of operations in the consolidated statements of operations. Asset Impairments Long-lived assets that are held and used are reviewed for impairment whenever events or changes in circumstances indicate carrying values may not be recoverable. Such reviews are performed in accordance with ASC 360. An impairment loss is indicated if the total future estimated undiscounted cash flows expected from an asset are less than its carrying value. An impairment charge is measured by the difference between an asset's carrying amount and fair value with the difference recorded in operating costs and expenses in the statements of operations. Fair values are determined by a variety of valuation methods, including appraisals, sales prices of similar assets and present value techniques. For further discussion of the Company's long-lived asset impairments, refer to Note 9 , Asset Impairments . Investments accounted for by the equity method are reviewed for impairment in accordance with ASC 323, Investments-Equity Method and Joint Ventures , which requires that a loss in value of an investment that is an other-than-temporary decline should be recognized. The Company identifies and measures losses in the value of equity method investments based upon a comparison of fair value to carrying value. Debt Issuance Costs Debt issuance costs are capitalized and amortized as interest expense on a basis which approximates the effective interest method over the term of the related debt. Debt issuance costs related to the long term debt are presented as a direct deduction from the carrying amount of the related debt in both the current and prior periods. Debt issuance costs related to the senior secured revolving credit facility line of credit are recorded as a non-current asset on the balance sheet and are amortized over the term of the loan. Intangible Assets Intangible assets represent contractual rights held by the Company. The Company recognizes specifically identifiable intangible assets including power purchase agreements, leasehold improvements, customer relationships, customer contracts, and development rights when specific rights and contracts are acquired. These intangible assets are amortized primarily on a straight-line basis. Notes Receivable Notes receivable consist of receivables related to the financing of required network upgrades. The notes issued with respect to network upgrades will be repaid within a 5 -year period following the date each facility reached commercial operations. Income Taxes The Company accounts for income taxes using the liability method in accordance with ASC 740, Income Taxes , or ASC 740, which requires that the Company use the asset and liability method of accounting for deferred income taxes and provide deferred income taxes for all significant temporary differences. The Company has two categories of income tax expense or benefit — current and deferred, as follows: • Current income tax expense or benefit consists solely of current taxes payable less applicable tax credits, and • Deferred income tax expense or benefit is the change in the net deferred income tax asset or liability, excluding amounts charged or credited to accumulated other comprehensive income. The Company reports some of its revenues and expenses differently for financial statement purposes than for income tax return purposes, resulting in temporary and permanent differences between the Company's financial statements and income tax returns. The tax effects of such temporary differences are recorded as either deferred income tax assets or deferred income tax liabilities in the Company's consolidated balance sheets. The Company measures its deferred income tax assets and deferred income tax liabilities using income tax rates that are currently in effect. The Company believes it is more likely than not that the results of future operations will generate sufficient taxable income which includes the future reversal of existing taxable temporary differences to realize deferred tax assets, net of valuation allowances. In arriving at this conclusion to utilize projections of future profit before tax in its estimate of future taxable income, the Company considered the profit before tax generated in recent years. A valuation allowance is recorded to reduce the net deferred tax assets to an amount that is more-likely-than-not to be realized. The Company accounts for uncertain tax positions in accordance with ASC 740, which applies to all tax positions related to income taxes. Under ASC 740, tax benefits are recognized when it is more-likely-than-not that a tax position will be sustained upon examination by the authorities. The benefit recognized from a position that has surpassed the more-likely-than-not threshold is the largest amount of benefit that is more than 50% likely to be realized upon settlement. The Company recognizes interest and penalties accrued related to uncertain tax benefits as a component of income tax expense. In accordance with ASC 740 and as discussed further in Note 14 , Income Taxes , changes to existing net deferred tax assets or valuation allowances or changes to uncertain tax benefits, are recorded to income tax expense. Revenue Recognition Thermal Revenues Steam and chilled water revenue is recognized 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. 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. Power Purchase Agreements, or PPAs The majority of the Company’s revenues are obtained through PPAs or other contractual agreements, which are accounted for as operating leases under ASC 840. 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. Certain of these leases have no minimum lease payments and all of the rental income under these leases is recorded as contingent rent on an actual basis when the electricity is delivered. The contingent rental income recognized in the years ended December 31, 2016 , 2015 , and 2014 was $553 million , $416 million , and $296 million , respectively. Derivative Financial Instruments The Company accounts for derivative financial instruments under ASC 815, Derivatives and Hedging , or ASC 815, which requires the Company to record all derivatives on the balance sheet at fair value unless they qualify for a NPNS exception. Changes in the fair value of non-hedge derivatives are immediately recognized in earnings. Changes in the fair value of derivatives accounted for as hedges, if elected for hedge accounting, are either: • Recognized in earnings as an offset to the changes in the fair value of the related hedged assets, liabilities and firm commitments; or • Deferred and recorded as a component of accumulated OCI until the hedged transactions occur and are recognized in earnings. The Company's primary derivative instruments are power purchase or sale contracts used to mitigate variability in earnings due to fluctuations in market prices, fuels purchase contracts used to control customer reimbursable fuel cost, and interest rate instruments used to mitigate variability in earnings due to fluctuations in interest rates. On an ongoing basis, the Company assesses the effectiveness of all derivatives that are designated as hedges for accounting purposes in order to determine that each derivative continues to be highly effective in offsetting changes in fair values or cash flows of hedged items. Internal analyses that measure the statistical correlation between the derivative and the associated hedged item determine the effectiveness of such a contract designated as a hedge. If it is determined that the derivative instrument is not highly effective as a hedge, hedge accounting will be discontinued prospectively. In this case, the gain or loss previously deferred in accumulated OCI would be frozen until the underlying hedged item is delivered unless the transaction being hedged is no longer probable of occurring in which case the amount in OCI would be immediately reclassified into earnings. If the derivative instrument is terminated, the effective portion of this derivative deferred in accumulated OCI will be frozen until the underlying hedged item is delivered. Revenues and expenses on contracts that qualify for the NPNS exception are recognized when the underlying physical transaction is delivered. While these contracts are considered derivative financial instruments under ASC 815, they are not recorded at fair value, but on an accrual basis of accounting. If it is determined that a transaction designated as NPNS no longer meets the scope exception, the fair value of the related contract is recorded on the balance sheet and immediately recognized through earnings. Concentrations of Credit Risk Financial instruments which potentially subject the Company to concentrations of credit risk consist primarily of accounts receivable, notes receivable and derivative instruments, which are concentrated within entities engaged in the energy and financial industry. These industry concentrations may impact the overall exposure to credit risk, either positively or negatively, in that the customers may be similarly affected by changes in economic, industry or other conditions. In addition, many of the Company's projects have only one customer. However, the Company believes that the credit risk posed by industry concentration is offset by the diversification and creditworthiness of its customer base. See Note 6 , Fair Value of Financial Instruments , for a further discussion of derivative concentrations and Note 13 , Segment Reporting , for concentration of counterparties. Fair Value of Financial Instruments The carrying amount of cash and cash equivalents, restricted cash, accounts receivable, accounts receivable - affiliate, accounts payable, current portion of account payable - affiliate, and accrued expenses and other current liabilities approximate fair value because of the short-term maturity of these instruments. See Note 6 , Fair Value of Financial Instruments , for a further discussion of fair value of financial instruments. Asset Retirement Obligations Asset retirement obligations, or AROs, are accounted for in accordance with ASC 410-20, Asset Retirement Obligations, or ASC 410-20. Retirement obligations associated with long-lived assets included within the scope of ASC 410-20 are those for which a legal obligation exists under enacted laws, statutes, and written or oral contracts, including obligations arising under the doctrine of promissory estoppel, and for which the timing and/or method of settlement may be conditional on a future event. ASC 410-20 requires an entity to recognize the fair value of a liability for an ARO in the period in which it is incurred and a reasonable estimate of fair value can be made. Upon initial recognition of a liability for an ARO, the asset retirement cost is capitalized by increasing the carrying amount of the related long-lived asset by the same amount. Over time, the liability is accreted to its future value, while the capitalized cost is depreciated over the useful life of the related asset. The Company's AROs are primarily related to the future dismantlement of equipment on leased property and environmental obligations related to site closures and fuel storage facilities. The Company records AROs as part of other non-current liabilities on its balance sheet. The following table represents the balance of ARO obligations as of December 31, 2016 and 2015 , along with the additions and accretion related to the Company's ARO obligations for the year ended December 31, 2016 : (In millions) Balance as of December 31, 2015 $ 43 Revisions in estimates for current obligations 2 Accretion — expense 3 Balance as of December 31, 2016 $ 48 Guarantees The Company enters into various contracts that include indemnification and guarantee provisions as a routine part of its business activities. Examples of these contracts include operation and maintenance agreements, service agreements, commercial sales arrangements and other types of contractual agreements with vendors and other third parties, as well as affiliates. These contracts generally indemnify the counterparty for tax, environmental liability, litigation and other matters, as well as breaches of representations, warranties and covenants set forth in these agreements. Because many of the guarantees and indemnities the Company issues to third parties and affiliates do not limit the amount or duration of its obligations to perform under them, there exists a risk that the Company may have obligations in excess of the amounts agreed upon in the contracts mentioned above. For those guarantees and indemnities that do not limit the liability exposure, the Company may not be able to estimate what the liability would be, until a claim is made for payment or performance, due to the contingent nature of these contracts. Investments Accounted for by the Equity Method The Company has investments in various energy projects accounted for by the equity method, four of which are VIEs, where the Company is not a primary beneficiary, and two of which are owned by a subsidiary that is consolidated as a VIE, as described in Note 5 , Investments Accounted for by the Equity Method and Variable Interest Entities . The equity method of accounting is applied to these investments in affiliates because the ownership structure prevents the Company from exercising a controlling influence over the operating and financial policies of the projects. Under this method, equity in pre-tax income or losses of the investments is reflected as equity in earnings of unconsolidated affiliates. Distributions from equity method investments that represent earnings on the Company's investment are included within cash flows from operating activities and distributions from equity method investments that represent a return of the Company's investment are included within cash flows from investing activities. Sale Leaseback Arrangements The Company is party to sale-leaseback arrangements that provide for the sale of certain assets to a third party and simultaneous leaseback to the Company. In accordance with ASC 840-40, Sale-Leaseback Transactions , if the seller-lessee retains, through the leaseback, substantially all of the benefits and risks incident to the ownership of the property sold, the sale-leaseback transaction is accounted for as a financing arrangement. An example of this type of continuing involvement would include an option to repurchase the assets or the buyer-lessor having the option to sell the assets back to the Company. This provision is included in most of the Company’s sale-leaseback arrangements. As such, the Company accounts for these arrangements as financings. Under the financing method, the Company does not recognize as income any of the sale proceeds received from the lessor that contractually constitutes payment to acquire the assets subject to these arrangements. Instead, the sale proceeds received are accounted for as financing obligations and leaseback payments made by the Company are allocated between interest expense and a reduction to the financing obligation. Interest on the financing obligation is calculated using the Company’s incremental borrowing rate at the inception of the arrangement on the outstanding financing obligation. Judgment is required to determine the appropriate borrowing rate for the arrangement and in determining any gain or loss on the transaction that would be recorded either at the end of or over the lease term. Business Combinations The Company accounts for its business combinations in accordance with ASC 805, Business Combinations, or ASC 805. For third party acquisitions, ASC 805 requires an acquirer to recognize and measure in its financial statements the identifiable assets acquired, the liabilities assumed, and any noncontrolling interest in the acquiree at fair value at the acquisition date. It also recognizes and measures the goodwill acquired or a gain from a bargain purchase in the business combination and determines what information to disclose to enable users of an entity's financial statements to evaluate the nature and financial effects of the business combination. In addition, transaction costs are expensed as incurred. For acquisitions that relate to entities under common control, ASC 805 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 of from the date the entities were under common control (if later than the beginning of the financial statement period). The difference between the cash paid and historical value of the entities' equity is recorded as a distribution/contribution from/to NRG with the offset to noncontrolling interest. Transaction costs are expensed as incurred. 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 amount of assets and liabilities and disclosures of contingent assets and liabilities as of the date of the consolidated financial statements. They also impact the reported amount of net earnings during the reporting period. Actual results could be different from these estimates. In recording transactions and balances resulting from business operations, the Company uses estimates based on the best information available. Estimates are used for such items as plant depreciable lives, tax provisions, uncollectible accounts, environmental liabilities, acquisition accounting and legal costs incurred in connection with recorded loss contingencies, among others. In addition, estimates are used to test long-lived assets for impairment and to determine the fair value of impaired assets. As better information becomes available or actual amounts are determinable, the recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates. Tax Equity Arrangements Certain portions of the Company’s noncontrolling interests in subsidiaries represent third-party interests in the net assets under certain tax equity arrangements, which are consolidated by the Company, that have been entered into to finance the cost of wind facilities eligible for certain tax credits. Additionally, certain portions of the Company’s investments in unconsolidated affiliates reflect the Company’s interests in tax equity arrangements, that are not consolidated by the Company, that have been entered into to finance the cost of distributed solar energy systems under operating leases or PPAs eligible for certain tax credits. The Company has determined that the provisions in the contractual agreements of these structures represent substantive profit sharing arrangements. Further, the Company has determined that the appropriate methodology for calculating the noncontrolling interest and investment in unconsolidated affiliates that reflects the substantive profit sharing arrangements is a balance sheet approach utilizing the hypothetical liquidation at book value, or HLBV, method. Under the HLBV method, the amounts reported as noncontrolling interests and investment in unconsolidated affiliates represent the amounts the investors to the tax equity arrangements would hypothetically receive at each balance sheet date under the liquidation provisions of the contractual agreements, assuming the net assets of the funding structures were liquidated at their recorded amounts determined in accordance with GAAP. The investors’ interests in the results of operations of the funding structures are determined as the difference in noncontrolling interests and investment in unconsolidated affiliates at the start and end of each reporting period, after taking into account any capital transactions between the structures and the funds’ investors. The calculations utilized to apply the HLBV method include estimated calculations of taxable income or losses for each reporting period. Reclassifications Certain prior year amounts have been reclassified for comparative purposes. Recent Accounting Developments ASU 2016-18 — In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230) , Restricted Cash, or ASU No. 2016-18. The amendments of ASU No. 2016-18 were issued to address the diversity in classification and presentation of changes in restricted cash and restricted cash equivalents on the statement of cash flows which is currently not addressed under Topic 230. The amendments of ASU No. 2016-18 would require an entity to include amounts generally described as restricted cash and restricted cash equivalents with cash and cash equivalents when reconciling the beginning of period and end of period total amounts on the statement of cash flows. The amendments of ASU No. 2016-18 are effective for annual reporting periods beginning after December 15, 2017, and interim periods within those annual periods. Early adoption is permitted and the adoption of ASU No. 2016-18 should be applied retrospectively. The Company is currently evaluating the impact of the standard on the Company’s statement of cash flows. ASU 2016-16 — In October 2016, the FASB issued ASU No. 2016-16, Income Taxes (Topic 740) , Intra-Entity Transfers of Assets Other Than Inventory, or ASU No. 2016-16. The amendments of ASU No. 2016-16 were issued to improve the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. Current GAAP prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party which has resulted in diversity in practice and increased complexity within financial reporting. The amendments of ASU No. 2016-16 would require an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs and do not require new disclosure requirements. The amendments of ASU No. 2016-16 are effective for annual reporting periods beginning after December 15, 2017, and interim periods within those annual periods. Early adoption is permitted and the adoption of ASU No. 2016-16 should be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The Company is currently evaluating the impact of the standard on the Company’s results of operations, cash flows and financial position. ASU 2016-15 — In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230) , Classification of Certain Cash Receipts and Cash Payments, or ASU No. 2016-15. The amendments of ASU No. 2016-15 were issued to address eight specific cash flow issues for which stakeholders have indicated to the FASB that a diversity in practice existed in how entities were presenting and classifying these items in the statement of cash flows. The issues addressed by ASU No. 2016-15 include but are not limited to the classification of debt prepayment and debt extinguishment costs, payments made for contingent consideration for a business combination, proceeds from the settlement of insurance proceeds, distributions received from equity method investees and separately identifiable cash flows and the application of the predominance principle. The amendments of ASU No. 2016-15 are effective for public entities for fiscal years beginning after December 15, 2017 and interim periods in those fiscal years. Early adoption is permitted, including adoption in an interim fiscal period with all amendments adopted in the same period. The adoption of ASU No. 2016-15 is required to be applied retrospectively. The Company is currently evaluating the impact of the standard on the Company's statement of cash flows. ASU 2016-07 — In March 2016, the FASB issued ASU No. 2016-07, Investments - Equity Method and Joint Ventures (Topic 323), or ASU No. 2016-07. The amendments of ASU No. 2016-07 eliminate the requirement that when an investment qualifies for use of the equity method as a result of an increase in the level of ownership interest or degree of influence, an investor must adjust the investment, results of operations, and retained earnings retroactively on a step-by-step basis as if the equity method had been in effect during all previous periods that the investment had been held. The amendments require that the equity method investor add the cost of acquiring the additional interest in the investee to the current basis of the investor's previously held interest and adopt the equity method of accounting with no retroactive adjustment to the investment. In addition, ASU No. 2016-07 requires that an entity that has an available-for-sale equity security that becomes qualified for the equity method of accounting recognize through earnings the unrealized holding gain or loss in accumulated other comprehensive income at the date the investment becomes qualified for use of the equity method. The Company adopted this standard effective January 1, 2017. The adoption of ASU No. 2016-07 is required to be applied prospectively. The Company does not expect the standard to have a material impact on its results of operations, cash flows and financial position. ASU 2016-02 — In 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 expects to adopt the standard effective January 1, 2019 utilizing the required modified retrospective approach for the earliest period presented. The Company 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. As this review is still in process, it is currently not practicable to quantify the impact of adopting the ASU at this time. ASU 2016-01 — In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities , or ASU No. 2016-01. The amendments of ASU No. 2016-01 eliminate available-for-sale classification of equity investments and require that equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be generally measured at fair value with changes in fair value recognized in net income. Further, the amendments require that financial assets and financial liabilities to be presented separately in the notes to the financial statements, grouped by measurement category and form of financial asset. The guidance in ASU No. 2016-01 is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods within those annual periods. The Company is cu

Business Acquisitions

Business Acquisitions	12 Months Ended
	Dec. 31, 2016
Business Acquisition	Business Acquisitions 2016 Acquisitions CVSR Drop Down — Prior to September 1, 2016, the Company had a 48.95% interest in CVSR, which was accounted for as an equity method investment. On September 1, 2016, the Company acquired from NRG the remaining 51.05% interest of CVSR Holdco LLC, which indirectly owns the CVSR solar facility, CVSR Drop Down, for total cash consideration of $78.5 million , plus an immaterial working capital adjustment. The acquisition was funded with cash on hand. The Company also assumed additional debt of $496 million , which represents 51.05% of the CVSR project level debt and 51.05% of the notes issued under the CVSR Holdco Financing Agreement, as further described in Note 10 , Long-term Debt . In connection with the retrospective adjustment of prior periods, the Company now consolidates CVSR and 100% of its debt, consisting of $771 million of project level debt and $200 million of notes issued under the CVSR Holdco Financing Agreement as of September 1, 2016 . 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 a distribution to NRG with the offset to noncontrolling interest. Because 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. In connection with the retrospective adjustment of prior periods, the Company has removed the equity method investment from all prior periods and adjusted its financial statements to reflect its results of operations, financial position and cash flows as if it had consolidated CVSR from the beginning of the financial statement period. As of June 30, 2016, the Company's recast consolidated balance sheet included a net receivable of $ 67 million related to current litigation with SunPower pursuant to indemnities in the project. The agreement between NRG and the Company for the CVSR Drop Down acquisition specified that all amounts related to the litigation with SunPower were excluded from the acquisition. Accordingly, prior to close of the transaction, the net receivable was transferred to NRG as a net reduction to its ownership interest in CVSR. The following is the summary of historical net liabilities assumed in connection with the CVSR Drop Down as of September 1, 2016: CVSR (In millions) Current assets $ 95 Property, plant and equipment 826 Non-current assets 13 Total assets 934 Debt (a) 966 Other current and non-current liabilities 12 Total liabilities 978 Net liabilities assumed (44 ) Accumulated other comprehensive loss (25 ) Historical net liabilities assumed $ (19 ) (a) Net of deferred financing costs of $5 million . The Company incurred and expensed acquisition-related transaction costs related to the acquisition of CVSR of $1 million for the year ended December 31, 2016. Since the acquisition date, CVSR has contributed $22 million in operating revenues and a $2 million in net loss to the Company. 2015 Acquisitions November 2015 Drop Down Assets from NRG — On November 3, 2015, the Company acquired the November 2015 Drop Down Assets, a portfolio of 12 wind facilities totaling 814 net MW, from NRG for cash consideration of $209 million , subject to working capital adjustments. In February 2016, NRG made a final working capital payment of $2 million , reducing total cash consideration to $207 million . The Company is responsible for its pro-rata share of non-recourse project debt of $193 million and noncontrolling interest associated with a tax equity structure of $159 million (as of the acquisition date). The Company funded the acquisition with borrowings from its revolving credit facility. The assets and liabilities transferred to the Company relate to interests under common control by NRG and were recorded at historical cost. The difference between the cash paid and historical value of the entities' equity was recorded as a distribution from NRG with the offset to noncontrolling interest. The Class A interests of NRG Wind TE Holdco are owned by a tax equity investor, or TE Investor, who receives 99% of allocations of taxable income and other items until 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 8.53% . The Company generally receives 75% of CAFD until the flip point, at which time the allocations to the Company of CAFD change to 68.60% . If the flip point has not occurred by a specified date, 100% of CAFD is allocated to the TE Investor until the flip point occurs. NRG Wind TE Holdco is a VIE and the Company is the primary beneficiary, through its position as managing member, and consolidates NRG Wind TE Holdco. The following is a summary of assets and liabilities transferred in connection with the acquisition as of November 3, 2015: NRG Wind TE Holdco (In millions) Current assets $ 30 Property, plant and equipment 669 Non-current assets 177 Total assets 876 Debt 193 Other current and non-current liabilities 32 Total liabilities 225 Less: noncontrolling interest 282 Net assets acquired $ 369 Desert Sunlight — On June 29, 2015, the Company acquired 25% of the membership interest in Desert Sunlight Investment Holdings, LLC, which owns two solar photovoltaic facilities that total 550 MW, located in Desert Center, California from EFS Desert Sun, LLC, an affiliate of GE Energy Financial Services for a purchase price of $285 million . Power generated by the facilities is sold to Southern California Edison and Pacific Gas and Electric under long-term PPAs with approximately 20 years and 25 years of remaining contract life, respectively. The Company accounts for its 25% investment as an equity method investment. Spring Canyon — On May 7, 2015, the Company acquired a 90.1% interest in Spring Canyon II, a 32 MW wind facility, and Spring Canyon III, a 28 MW wind facility, each located in Logan County, Colorado, from Invenergy Wind Global LLC. The purchase price was funded with cash on hand. Power generated by Spring Canyon II and Spring Canyon III is sold to Platte River Power Authority under long-term PPAs, each with approximately 24 years of remaining contract life. University of Bridgeport Fuel Cell — On April 30, 2015, the Company completed the acquisition of the University of Bridgeport Fuel Cell project in Bridgeport, Connecticut from FuelCell Energy, Inc. The project added an additional 1.4 MW of thermal capacity to the Company's portfolio, with a 12 -year contract, with the option for a 7 -year extension. The acquisition is reflected in the Company's Thermal segment. January 2015 Drop Down Assets from NRG — On January 2, 2015, the Company acquired the following projects from NRG: (i) Laredo Ridge, an 80 MW wind facility located in Petersburg, Nebraska, (ii) Tapestry, which includes Buffalo Bear, a 19 MW wind facility in Buffalo, Oklahoma; Taloga, a 130 MW wind facility in Putnam, Oklahoma; and Pinnacle, a 55 MW wind facility in Keyser, West Virginia, and (iii) Walnut Creek, a 485 MW natural gas facility located in City of Industry, California, for total cash consideration of $489 million , including $9 million for working capital, plus assumed project-level debt of $737 million . The Company funded the acquisition with cash on hand and drawings under its revolving credit facility. The assets and liabilities transferred to the Company relate to interests under common control by NRG and were recorded at historical cost. The difference between the cash paid and the historical value of the entities' equity of $61 million , as well as $23 million of AOCL, was recorded as a distribution to NRG and reduced the balance of its noncontrolling interest. 2014 Acquisitions Alta Wind Portfolio Acquisition — On August 12, 2014, the Company acquired 100% of the membership interests of Alta Wind Asset Management Holdings, LLC, Alta Wind Company, LLC, Alta Wind X Holding Company, LLC and Alta Wind XI Holding Company, LLC, which collectively own seven wind facilities that total 947 MW located in Tehachapi, California, and a portfolio of associated land leases, or the Alta Wind Portfolio. Power generated by the Alta Wind Portfolio is sold to Southern California Edison under long-term PPAs with 21 years of remaining contract life for Alta I-V. The Alta Wind X and XI PPAs began in 2016 with a term of 22 years and sold energy and renewable energy credits on a merchant basis during the years ending December 31, 2015 and 2014. The purchase price for the Alta Wind Portfolio was $923 million , which consisted of a base purchase price of $870 million , as well as a payment for working capital of $53 million , plus the assumption of $1.6 billion of non-recourse project-level debt. In order to fund the purchase price, the Company completed an equity offering of 12,075,000 shares of its Class A common stock at an offering price of $54.00 per share on July 29, 2014, which resulted in net proceeds of $630 million , after underwriting discounts and expenses. In addition, on August 5, 2014, NRG Yield Operating LLC issued $500 million of Senior Notes, which bear interest at a rate of 5.375% and mature in August 2024. The acquisition was recorded as a business combination under ASC 805-50, with identifiable assets acquired and liabilities assumed provisionally recorded at their estimated fair values on the acquisition date. The accounting for the business combination was completed as of August 11, 2015, at which point the fair values became final. The following table summarizes the provisional amounts recognized for assets acquired and liabilities assumed as of December 31, 2014, as well as adjustments made through August 11, 2015, when the allocation became final. The purchase price of $923 million was allocated as follows: Acquisition Date Fair Value at December 31, 2014 Measurement period adjustments Revised Acquisition Date Assets (In millions) Cash $ 22 $ — $ 22 Current and non-current assets 49 (2 ) 47 Property, plant and equipment 1,304 6 1,310 Intangible assets 1,177 (6 ) 1,171 Total assets acquired 2,552 (2 ) 2,550 Liabilities Debt 1,591 — 1,591 Current and non-current liabilities 38 (2 ) 36 Total liabilities assumed 1,629 (2 ) 1,627 Net assets acquired $ 923 $ — $ 923 The Company incurred and expensed acquisition-related transaction costs related to the acquisition of the Alta Wind Portfolio of $2 million for the year ended December 31, 2014. June 2014 Drop Down Assets — On June 30, 2014, the Company acquired from NRG: (i) El Segundo, a 550 MW fast-start, gas-fired facility located in Los Angeles County, California; (ii) TA High Desert, a 20 MW solar facility located in Los Angeles County, California; and (iii) Kansas South, a 20 MW solar facility located in Kings County, California. The Company paid total cash consideration of $357 million , which represents a base purchase price of $349 million and $8 million of working capital adjustments. In addition, the acquisition included the assumption of $612 million of project-level debt. The assets and liabilities transferred to the Company relate to interests under common control by NRG and were recorded at historical cost in accordance with ASC 805-50. The difference between the cash proceeds and the historical value of the net assets was recorded as a distribution to NRG and reduced the balance of its noncontrolling interest. Since the transaction constituted a transfer of entities under common control, the guidance requires retrospective combination of the entities for all periods presented as if the combination has been in effect since the beginning of the financial statements period or the inception of common control (if later than the beginning of the financial statements period). Accordingly, the Company prepared its consolidated financial statements to reflect the transfer as if it had taken place from the beginning of the financial statements period.

Property, Plant and Equipment

Property, Plant and Equipment	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Property, Plant and Equipment Disclosure	Property, Plant and Equipment The Company’s major classes of property, plant, and equipment were as follows: December 31, 2016 December 31, 2015 Depreciable Lives (In millions) Facilities and equipment $ 6,215 $ 6,480 2 - 40 Years Land and improvements 171 171 Construction in progress (a) 25 9 Total property, plant and equipment 6,411 6,660 Accumulated depreciation (951 ) (782 ) Net property, plant and equipment $ 5,460 $ 5,878 (a) As of December 31, 2016, construction in progress includes $20 million of capital expenditures that relate to prepaid long-term service agreements primarily in the Conventional segment.

Investments Accounted for by th

Investments Accounted for by the Equity Method and Variable Interest Entities	12 Months Ended
	Dec. 31, 2016
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 2017 Drop Down Assets — On February 24, 2017, the Company and NRG entered into a definitive agreement regarding the acquisition of the following facilities: (i) a 16% interest (approximately 31% of NRG's 51% interest) in the Agua Caliente solar farm, one of the NRG ROFO assets, representing ownership of approximately 46 net MW of capacity. 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 and (ii) NRG's 50% interests in seven utility-scale solar farms located in Utah representing 265 net MW (based on cash to be distributed) of capacity that were part of NRG's recent acquisition of projects from SunEdison. These assets 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, from which NRG currently receives 50% of cash to be distributed. The Company expects to pay total cash consideration of $130 million and assume non-recourse project debt. The purchase price for the acquisition, which is subject to working capital adjustments to be calculated at close, is expected to be funded with cash on hand. The Company expects to record its interests in the acquired projects as equity method investments. Equity Method Investments The following table summarizes the Company's equity method investments as of December 31, 2016 : Name Economic Interest Investment Balance (In millions) Desert Sunlight 25% $282 GenConn (a) 50% 106 Elkhorn Ridge (b) 50.3% 85 San Juan Mesa (b) 56.3% 74 NRG DGPV Holdco 1 LLC (c) 95% 75 NRG DGPV Holdco 2 LLC (c) 95% 24 NRG RPV Holdco 1 LLC (c) 95% 71 Avenal 50% (7) Total equity investments in affiliates $710 (a) GenConn is a variable interest entity. (b) San Juan Mesa and Elkhorn Ridge are part of the Wind TE Holdco tax equity structure, as described below. San Juan Mesa and Elkhorn Ridge are owned 75% and 66.7% , respectively, by Wind TE Holdco. The Company owns 75% of the Class B interests in Wind TE Holdco. (c) Economic interest based on cash to be distributed. NRG DGPV Holdco 1 LLC, NRG DGPV Holdco 2 LLC, and NRG RPV Holdco 1 LLC are tax equity structures and VIEs. The related allocations are described below. As of December 31, 2016 and 2015 , the Company had $ 30 million and $ 39 million , respectively, of undistributed earnings from its equity method investments. The Company acquired its interest in Desert Sunlight on June 30, 2015, for $285 million , which resulted in a difference between the purchase price and the basis of the acquired assets and liabilities of $171 million . The difference is attributable to the fair value of the property, plant and equipment and power purchase agreements. The Company is amortizing the related basis difference to equity in earnings (losses) over the related useful life of the underlying assets acquired. Non-recourse project-level debt of unconsolidated affiliates The Company's pro-rata share of non-recourse debt held by unconsolidated affiliates was approximately $453 million as of December 31, 2016 . Avenal — The Company owns a 50% equity interest in Avenal, which consists of three solar PV projects in Kings County, California totaling approximately 45 MWs. Eurus Energy owns the remaining 50% of Avenal. Power generated by the projects is sold under a 20 -year PPA. On September 22, 2010, Avenal entered into a $35 million promissory note facility with the Company. Amounts drawn under the promissory note facility accrue interest at 4.5% per annum. Also, on September 22, 2010, Avenal entered into a $209 million financing arrangement with a syndicate of banks, or the Avenal Facility. As of December 31, 2016 and 2015 , Avenal had outstanding $134 million and $143 million , respectively, under the Avenal Facility. Desert Sunlight — Desert Sunlight 250 and Desert Sunlight 300 each entered into three distinct tranches of debt. As of December 31, 2016 and 2015 , Desert Sunlight had total debt outstanding of $1.1 billion under the three tranches. GenConn — GenConn has a $237 million project note with an interest rate of 4.73% and a maturity date of July 2041 and a 5-year, $35 million working capital facility that matures in 2018 which can be used to issue letters of credit at an interest rate of 1.875% per annum. As of December 31, 2016 and 2015 , $212 million and $220 million , respectively, were outstanding under the note. As of December 31, 2016 , $14 million was drawn on the working capital facility. The note is secured by all of the GenConn assets. The Company's maximum exposure to loss is limited to its equity investment in GenConn, which was $106 million as of December 31, 2016. NRG DGPV Holdco 2 LLC — On June 30, 2016, NRG DGPV4 Borrower LLC, a direct subsidiary of NRG DGPV Holdco 2 LLC entered into a financing agreement to fund the acquisition of projects by the tax equity fund. As of December 31, 2016 there was $21 million outstanding under the facility. The following tables present summarized financial information for the Company's significant equity method investments: Year Ended December 31, 2016 2015 2014 Income Statement Data: (In millions) GenConn Operating revenues $ 72 $ 78 $ 82 Operating income 38 40 40 Net income 26 28 28 Desert Sunlight Operating revenues $ 211 $ 206 Operating income 129 124 Net income 80 73 As of December 31, 2016 2015 Balance Sheet Data: (In millions) GenConn Current assets $ 36 $ 36 Non-current assets 389 416 Current liabilities 16 16 Non-current liabilities 196 215 Desert Sunlight Current assets $ 281 $ 310 Non-current assets 1,401 1,435 Current liabilities 64 82 Non-current liabilities 1,043 1,086 Variable Interest Entities, or VIEs Entities that are Consolidated NRG Wind TE Holdco — On November 3, 2015, the Company acquired 75% of the Class B interests of NRG Wind TE Holdco, or the November 2015 Drop Down Assets, which owns a portfolio of 12 wind facilities totaling 814 net MW, from NRG for total cash consideration of $209 million , as described in Note 3 , Business Acquisitions . In February 2016, NRG made a final working capital payment of $2 million , reducing total cash consideration to $207 million . NRG retained a 25% ownership of the Class B interest. The Class A interests of NRG Wind TE Holdco are owned by a tax equity investor, or TE Investor, who receives 99% of allocations of taxable income and other items until 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 8.53% . The Company generally receives 75% of CAFD until the flip point, at which time the allocations to the Company of CAFD change to 68.60% . If the flip point has not occurred by a specified date, 100% of CAFD is allocated to the TE Investor until the flip point occurs. NRG Wind TE Holdco is a VIE and the Company is the primary beneficiary, through its position as managing member, and consolidates NRG Wind TE Holdco. The Company utilizes the HLBV method to determine the net income or loss allocated to the TE Investor noncontrolling interest. Net income or loss attributable to the Class B interests is allocated to NRG's noncontrolling interest based on its 25% ownership interest. Alta TE Holdco — On June 30, 2015, the Company sold an economic interest in Alta TE Holdco to a financial institution in order to monetize certain cash and tax attributes, primarily PTCs. The financial institution, or Alta Investor, receives 99% of allocations of taxable income and other items until the flip point, which occurs when the Alta Investor obtains a specified return on its initial investment, at which time the allocations to the Alta Investor change to 5% . The Company received 100% of CAFD through December 31, 2015, and subsequently will receive 94.34% until the flip point, at which time the allocations to the Company of CAFD will change to 97.12% , unless the flip point will not have occurred by a specified date, which would result in 100% of CAFD allocated to the Alta Investor until the flip point occurs. Alta TE Holdco is a VIE and the Company is the primary beneficiary through its position as managing member, and therefore consolidates Alta TE Holdco, with the Alta Investor's interest shown as noncontrolling interest. The Company utilizes the HLBV method to determine the net income or loss allocated to the noncontrolling interest. The net proceeds of $119 million were reflected as noncontrolling interest in the Company's balance sheet. Spring Canyon — On May 7, 2015, the Company acquired a 90.1% of the Class B interests in Spring Canyon II, a 32 MW wind facility, and Spring Canyon III, a 28 MW wind facility, each located in Logan County, Colorado, from Invenergy Wind Global LLC. Invenergy owns 9.9% of the Class B interests. Prior to the acquisition date, the projects were financed with a partnership flip tax-equity structure with a financial institution, who owns the Class A interests, to monetize certain cash and tax attributes, primarily PTCs. Until the flip point, the Class A member will receive 34.81% of the cash distributions based on the projects’ production level and the Company and Invenergy will receive 65.19% . After the flip point, cash distributions are allocated 5% to the Class A member and 95% to the Company and Invenergy. Spring Canyon is a VIE and the Company is the primary beneficiary through its position as managing member, and therefore consolidates Spring Canyon. The Class A member and Invenergy's interests are shown as noncontrolling interest. The Company utilizes the HLBV method to determine the net income or loss allocated to the Class A member. Net income or loss attributable to the Class B interests is allocated to Invenergy's noncontrolling interest based on its 9.9% ownership interest. Summarized financial information for the Company's consolidated VIEs consisted of the following as of December 31, 2016 : (In millions) NRG Wind TE Holdco Alta TE Holdco Spring Canyon Other current and non-current assets $ 193 $ 17 $ 4 Property, plant and equipment 441 461 100 Intangible assets 2 274 — Total assets 636 752 104 Current and non-current liabilities 209 9 6 Total liabilities 209 9 6 Noncontrolling interest 139 107 67 Net assets less noncontrolling interests $ 288 $ 636 $ 31 Entities that are not Consolidated The Company has interests in entities that are considered VIEs under ASC 810, Consolidation , 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. NRG DGPV Holdco 1 LLC — On May 8, 2015, the Company and NRG entered into a partnership by forming NRG DGPV Holdco 1 LLC, or DGPV Holdco 1, the purpose of which is to own or purchase solar power generation projects and other ancillary related assets from NRG Renew LLC or its subsidiaries via intermediate funds, including: (i) a tax equity-financed portfolio of 10 recently completed community solar projects representing approximately 8 MW with a weighted average remaining PPA term of 19 years ; (ii) a tax equity-financed portfolio of approximately 12 commercial photovoltaic systems representing approximately 37 MW with a weighted average remaining PPA term of 18 years ; and (iii) a tax equity-financed portfolio of approximately 3 commercial photovoltaic systems representing approximately 1 MW with a weighted average remaining PPA term of 20 years . All of these investments relate to the Company's $100 million commitment to distributed solar projects in partnership with NRG. NRG DGPV Holdco 2 LLC — On February 29, 2016, the Company and NRG entered into an additional partnership by forming NRG DGPV Holdco 2 LLC, or DGPV Holdco 2, to own or purchase solar power generation projects as well as other ancillary related assets from NRG Renew LLC or its subsidiaries, via intermediate funds including: (i) a tax equity-financed portfolio of 18 projects representing approximately 28 MW with a weighted average remaining PPA term of 21 years ; and (ii) a tax equity-financed portfolio of 21 projects representing approximately 18 MW with a weighted average remaining PPA term of 20 years . Under this partnership, the Company committed to fund up to $50 million of capital. The Company's maximum exposure to loss is limited to its equity investment in DGPV Holdco 1 and DGPV Holdco 2, which was $99 million on a combined basis, of which $14 million was payable to NRG, as of December 31, 2016 . NRG RPV Holdco 1 LLC — On April 9, 2015, the Company and NRG entered into a partnership by forming NRG RPV Holdco 1 LLC, or RPV Holdco, that holds operating portfolios of residential solar assets developed by NRG's residential solar business, including: (i) an existing, unlevered portfolio of over 2,200 leases across nine states representing approximately 15 MW with a weighted average remaining lease term of approximately 19 years that was acquired outside of the partnership; and (ii) a tax equity-financed portfolio of approximately 5,400 leases representing approximately 31 MW, with a weighted average remaining lease term for the existing and new leases of approximately 19 years . In addition to the acquisition of the unlevered portfolio of leases, the Company had previously committed to fund up to $150 million of capital to invest in the tax equity financed portfolio. On February 29, 2016, the Company and NRG amended the RPV Holdco partnership agreement to reduce the aggregate commitment of $150 million to $100 million in connection with the formation of DGPV Holdco 2. On August 5, 2016, the Company and NRG amended the RPV Holdco partnership agreement to further reduce that capital commitment of $100 million to $60 million in connection with NRG’s change in business model approach in the residential solar business. As of December 31, 2016 , the Company had contributed $59 million of this amount. The Company's maximum exposure to loss is limited to its equity investment, which was $71 million as of December 31, 2016 .

Fair Value of Financial Instrum

Fair Value of Financial Instruments	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	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 December 31, 2016 As of December 31, 2016 As of December 31, 2015 Fair Value (a) Fair Value (a) Fair Value (a) (In millions) Level 1 Level 2 Level 2 Derivative assets: Commodity contracts $ 1 $ 1 $ — Interest rate contracts — 1 — Total assets $ 1 $ 2 — Derivative liabilities: Commodity contracts $ — $ 1 2 Interest rate contracts — 71 98 Total liabilities $ — $ 72 $ 100 (a) There were no assets or liabilities classified as Level 1 as of December 31, 2015 . There were no assets or liabilities classified Level 3 as of December 31, 2016 and 2015 .
Fair Value of Financial Instruments	Fair Value of Financial Instruments For cash and cash equivalents, restricted cash, accounts receivable — affiliate, accounts receivable, accounts payable, current portion of accounts payable — affiliate, accrued expenses and other liabilities, the carrying amount approximates 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 December 31, 2016 As of December 31, 2015 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Assets: Notes receivable, including current portion 30 30 47 47 Liabilities: Long-term debt, including current portion 5,770 5,769 5,656 5,538 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. 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 December 31, 2016 and 2015 : As of December 31, 2016 As of December 31, 2015 Level 2 Level 3 Level 2 Level 3 (In millions) Long-term debt, including current portion $ 1,455 $ 4,314 $ 978 $ 4,560 Recurring Fair Value Measurements The Company records its derivative assets and liabilities at fair market value on its consolidated balance sheet. There were no asset positions as of December 31, 2015. 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 December 31, 2016 As of December 31, 2016 As of December 31, 2015 Fair Value (a) Fair Value (a) Fair Value (a) (In millions) Level 1 Level 2 Level 2 Derivative assets: Commodity contracts $ 1 $ 1 $ — Interest rate contracts — 1 — Total assets $ 1 $ 2 — Derivative liabilities: Commodity contracts $ — $ 1 2 Interest rate contracts — 71 98 Total liabilities $ — $ 72 $ 100 (a) There were no assets or liabilities classified as Level 1 as of December 31, 2015 . There were no assets or liabilities classified Level 3 as of December 31, 2016 and 2015 . 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 for interest rate swaps, is calculated based on credit default swaps utilizing the bilateral method. For commodities, to the extent that NRG's net exposure under a specific master agreement is an asset, the Company uses the counterparty's default swap rate. If the exposure under a specific master agreement is a liability, the Company uses NRG's 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 December 31, 2016 , the credit reserve resulted in a $1 million increase in fair value in OCI. It is possible that future market prices could vary from those used in recording assets and liabilities and such variations could be material. Concentration of Credit Risk In addition to the credit risk discussion as disclosed in Note 2 , Summary of Significant Accounting Policies , the following item 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) daily monitoring of counterparties' credit limits; (iii) the use of credit mitigation measures such as margin, collateral, prepayment arrangements, or volumetric limits; (iv) the use of payment netting agreements; and (v) the use of master netting agreements that allow for the netting of positive and negative exposures of various contracts associated with a single counterparty. Risks surrounding counterparty performance and credit could ultimately impact the amount and timing of expected cash flows. The Company seeks to mitigate counterparty risk by having a diversified portfolio of counterparties. Counterparty credit exposure includes credit risk exposure under certain long-term agreements, including solar and other PPAs. As external sources or observable market quotes are not available to estimate such exposure, the Company estimates the exposure related to these contracts based on various techniques including but not limited to internal models based on a fundamental analysis of the market and extrapolation of observable market data with similar characteristics. Based on these valuation techniques, as of December 31, 2016 , credit risk exposure to these counterparties attributable to the Company's ownership interests was approximately $2.6 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	12 Months Ended
	Dec. 31, 2016
Accounting for Derivative Instruments and Hedging Activities Disclosure [Abstract]
Accounting for Derivative Instruments and Hedging Activities	Accounting for Derivative Instruments and Hedging Activities ASC 815 requires the Company to recognize all derivative instruments on the balance sheet as either assets or liabilities and to measure them at fair value each reporting period unless they qualify for a NPNS exception. The Company may elect to designate certain derivatives as cash flow hedges, if certain conditions are met, and defer the effective portion of the change in fair value of the derivatives to accumulated OCI/OCL, until the hedged transactions occur and are recognized in earnings. The ineffective portion of a cash flow hedge is immediately recognized in earnings. For derivatives that are not designated as cash flow hedges or do not qualify for hedge accounting treatment, the changes in the fair value will be immediately recognized in earnings. Certain derivative instruments may qualify for the NPNS exception and are therefore exempt from fair value accounting treatment. ASC 815 applies to the Company's energy related commodity contracts and interest rate swaps. Energy-Related Commodities To manage the commodity price risk associated with its competitive supply activities and the price risk associated with wholesale power sales, the Company may enter into derivative hedging instruments, namely, forward contracts that commit the Company to sell energy commodities or purchase fuels/electricity in the future. The objectives for entering into derivatives contracts designated as hedges include fixing the price for a portion of anticipated future electricity sales and fixing the price of a portion of anticipated fuel/electricity purchases for the operation of its subsidiaries. As of December 31, 2016 , the Company had forward contracts for the purchase of fuel commodities relating to the forecasted usage of the Company’s district energy centers extending through 2018 and electricity contracts to supply retail power to the Company's district energy centers extending through 2020. At December 31, 2016 , these contracts were not designated as cash flow or fair value hedges. Also, as of December 31, 2016 , the Company had other energy-related contracts that did not meet the definition of a derivative instrument or qualified for the NPNS exception and were therefore exempt from fair value accounting treatment as follows: • Power tolling contracts through 2039, and • Natural gas transportation contracts through 2028. Interest Rate Swaps The Company is exposed to changes in interest rates through the issuance of variable rate debt. In order to manage interest rate risk, it enters into interest rate swap agreements. As of December 31, 2016 , the Company had interest rate derivative instruments on non-recourse debt extending through 2031, most of which are designated as cash flow hedges. Volumetric Underlying Derivative Transactions The following table summarizes the net notional volume buy/(sell) of the Company's open derivative transactions broken out by commodity as of December 31, 2016 and 2015 : Total Volume December 31, 2016 December 31, 2015 Commodity Units (In millions) Natural Gas MMBtu 3 4 Interest Dollars $ 1,839 $ 1,991 Fair Value of Derivative Instruments There were no derivative asset positions on the balance sheet as of December 31, 2015 . The following table summarizes the fair value within the derivative instrument valuation on the balance sheet: Fair Value Derivative Assets Derivative Liabilities December 31, 2016 December 31, 2016 December 31, 2015 (In millions) Derivatives Designated as Cash Flow Hedges: Interest rate contracts current $ — $ 26 $ 34 Interest rate contracts long-term 1 39 56 Total Derivatives Designated as Cash Flow Hedges 1 65 90 Derivatives Not Designated as Cash Flow Hedges : Interest rate contracts current — 2 3 Interest rate contracts long-term — 4 5 Commodity contracts current 2 1 2 Total Derivatives Not Designated as Cash Flow Hedges 2 7 10 Total Derivatives $ 3 $ 72 $ 100 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 December 31, 2016 , there was no outstanding collateral paid or received. As of December 31, 2015 , there were no offsetting amounts at the counterparty master agreement level or outstanding collateral paid or received. The following table summarizes the offsetting of derivatives by counterparty master agreement level as of December 31, 2016 : Gross Amounts Not Offset in the Statement of Financial Position As of December 31, 2016 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ 2 $ — $ 2 Derivative liabilities (1 ) — (1 ) Total commodity contracts 1 — 1 Interest rate contracts: Derivative assets 1 (1 ) — Derivative liabilities (71 ) 1 (70 ) Total interest rate contracts (70 ) — (70 ) Total derivative instruments $ (69 ) $ — $ (69 ) 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, net of tax: Year ended December 31, 2016 2015 2014 (In millions) Accumulated OCL beginning balance $ (83 ) $ (76 ) $ (16 ) Reclassified from accumulated OCL to income due to realization of previously deferred amounts 13 14 14 Mark-to-market of cash flow hedge accounting contracts — (21 ) (74 ) Accumulated OCL ending balance, net of income tax benefit of $16, $16 and $6, respectively $ (70 ) $ (83 ) $ (76 ) Accumulated OCL attributable to noncontrolling interests (42 ) (56 ) (67 ) Accumulated OCL attributable to NRG Yield, Inc. $ (28 ) $ (27 ) $ (9 ) Losses expected to be realized from OCL during the next 12 months, net of income tax benefit of $3 $ 16 Amounts reclassified from accumulated OCL into income and amounts recognized in income from the ineffective portion of cash flow hedges are recorded to interest expense. There was no ineffectiveness for the years ended December 31, 2016 , 2015 and 2014 . Accounting guidelines require a high degree of correlation between the derivative and the hedged item throughout the period in order to qualify as a cash flow hedge. As of December 31, 2016 , the Company's regression analysis for Viento Funding II interest rate swaps, while positively correlated, did not meet the required threshold for cash flow hedge accounting. As a result, the Company de-designated the Viento Funding II cash flow hedges as of December 31, 2016 , and will prospectively mark these derivatives to market through the income statement. Impact of Derivative Instruments on the Statements of Income 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 years ended December 31, 2016 , 2015 and 2014 the impact to the consolidated statements of income was a gain of $2 million , $16 million and a loss of $22 million , respectively. A portion of the Company’s derivative commodity contracts relates to its Thermal Business for the purchase of fuel/electricity commodities based on the forecasted usage of the thermal district energy centers. Realized gains and losses on these contracts are reflected in the 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 income for these contracts. In 2015 and 2014, commodity contracts also hedged the forecasted sale of power for the Elbow Creek until the start of the PPA with NRG Power Marketing LLC, or Power Marketing, with effective date of November 1, 2015. The effect of these commodity hedges was recorded to operating revenues. For the years ended December 31, 2015 and 2014 , the impact to the consolidated statements of income was an unrealized loss of $2 million and a gain of $2 million , respectively. See Note 6 , Fair Value of Financial Instruments , for a discussion regarding concentration of credit risk.

Intangible Assets

Intangible Assets	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Intangible Assets	Intangible Assets Intangible Assets — The Company's intangible assets as of December 31, 2016 and 2015 primarily reflect intangible assets established from its business acquisitions and are comprised of the following: • PPAs — Established predominantly with the acquisitions of the Alta Wind Portfolio, Walnut Creek, Tapestry and Laredo Ridge, these represent the fair value of the PPAs acquired. These will be amortized, generally on a straight-line basis, over the term of the PPA. • Leasehold Rights — Established with the acquisition of the Alta Wind Portfolio, this represents the fair value of contractual rights to receive royalty payments equal to a percentage of PPA revenue from certain projects. These will be amortized on a straight-line basis. • Customer relationships — Established with the acquisition of NRG Energy Center Phoenix and NRG Energy Center Omaha, these intangibles represent the fair value at the acquisition date of the businesses' customer base. The customer relationships are amortized to depreciation and amortization expense based on the expected discounted future net cash flows by year. • Customer contracts — Established with the acquisition of NRG Energy Center Phoenix, these intangibles represent the fair value at the acquisition date of contracts that primarily provide chilled water, steam and electricity to its customers. These contracts are amortized to revenues based on expected volumes. • Emission Allowances — These intangibles primarily consist of SO 2 and NO x emission allowances established with the El Segundo and Walnut Creek acquisitions. These emission allowances are held-for-use and are amortized to cost of operations, with NO x allowances amortized on a straight-line basis and SO 2 allowances amortized based on units of production. • Development rights — Arising primarily from the acquisition of solar businesses in 2010 and 2011, these intangibles are amortized to depreciation and amortization expense on a straight-line basis over the estimated life of the related project portfolio. • Other — Consists of the acquisition date fair value of the contractual rights to a ground lease for South Trent and to utilize certain interconnection facilities for Blythe, as well as land rights acquired in connection with the acquisition of Elbow Creek. The following tables summarize the components of intangible assets subject to amortization: Year ended December 31, 2016 PPAs Leasehold Rights Customer Customer Contracts Emission Allowances Development Other Total (In millions) January 1, 2016 $ 1,264 $ 86 $ 66 $ 15 $ 15 $ 3 $ 6 $ 1,455 Other — — — — (6 ) — — (6 ) December 31, 2016 1,264 86 66 15 9 3 6 1,449 Less accumulated amortization (138 ) (9 ) (4 ) (7 ) (2 ) (1 ) (2 ) (163 ) Net carrying amount $ 1,126 $ 77 $ 62 $ 8 $ 7 $ 2 $ 4 $ 1,286 Year ended December 31, 2015 PPAs Leasehold Rights Customer Relationships Customer Contracts Emission Allowances Development Rights Other Total (In millions) January 1, 2015 $ 1,270 $ 86 $ 66 $ 15 $ 16 $ 3 $ 6 $ 1,462 Other (6 ) — — — (1 ) — — (7 ) December 31, 2015 1,264 86 66 15 15 3 6 1,455 Less accumulated amortization (75 ) (5 ) (3 ) (6 ) (1 ) (1 ) (2 ) (93 ) Net carrying amount $ 1,189 $ 81 $ 63 $ 9 $ 14 $ 2 $ 4 $ 1,362 The Company recorded amortization expense of $70 million , $55 million and $30 million during the years ended December 31, 2016 , 2015 and 2014 . Of these amounts, $69 million , $54 million and $29 million for the years ended December 31, 2016 , 2015 and 2014 , respectively, were recorded to contract amortization expense and reduced operating revenues in the consolidated statements of income. The Company estimates the future amortization expense for its intangibles to be $71 million for the next five years through 2021. Out-of-market contracts — The out-of-market contract liability represents the out-of-market value of the PPAs for the Blythe solar project and Spring Canyon wind projects and the out-of-market value of the land lease for Alta Wind XI Holding Company, LLC, as of their respective acquisition dates. The Blythe solar project's liability of $4 million is recorded to other non-current liabilities on the consolidated balance sheet and is amortized to revenue in the consolidated statements of income on a units-of-production basis over the twenty -year term of the agreement. Spring Canyon's liability of $3 million is recorded to other non-current liabilities and is amortized to revenue on a straight-line basis over the twenty-five year term of the agreement. The Alta Wind XI Holding Company, LLC's liability of $5 million is recorded to other non-current liabilities and is amortized to cost of operations on a straight-line basis over the term of the land lease. At December 31, 2016 , accumulated amortization of out-of-market contracts was $3 million and amortization expense was $1 million for the years ended December 31, 2016 and 2015 .

Asset Impairments Asset Impairm

Asset Impairments Asset Impairments (Notes)	12 Months Ended
	Dec. 31, 2016
Asset Impairments [Abstract]
Asset Impairment Charges [Text Block]	Asset Impairments During the fourth quarter of 2016, as the Company updated its estimated cash flows in connection with the preparation and review of the Company's annual budget, the Company determined that the cash flows for the Elbow Creek and Goat Wind projects located in Texas and the Forward project in Pennsylvania were below the carrying value of the related assets, primarily driven by declining merchant power prices in post-contract periods, and that the assets were considered impaired. These projects were acquired in connection with the acquisition of the November 2015 Drop Down Assets and were recorded in the Renewables segment of the Company. The projects were recorded at historical cost at acquisition date as they were related to interests under common control by NRG. The fair value of the facilities was determined using an income approach by applying a discounted cash flow methodology to the long-term budgets for each respective plant. The income approach utilized estimates of discounted future cash flows, which were Level 3 fair value measurement and include key inputs, such as forecasted power prices, operations and maintenance expense, and discount rates. The Company measured the impairment loss as the difference between the carrying amount and the fair value of the assets and recorded impairment losses of $117 million , $60 million and $6 million for Elbow Creek, Goat Wind, and Forward, respectively.

Long-term Debt

Long-term Debt	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Long-term Debt	Long-term Debt The Company's borrowings, including short term and long term portions consisted of the following: December 31, 2016 December 31, 2015 Interest rate % (a) Letters of Credit Outstanding at December 31, 2016 (In millions, except rates) 2026 Senior Notes $ 350 $ — 5.000 2024 Senior Notes 500 500 5.375 2020 Convertible Notes (b) 271 266 3.250 2019 Convertible Notes (c) 335 330 3.500 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 (d) — 306 L+2.500 $ 60 Project-level debt: Alpine, due 2022 145 154 L+1.750 37 Alta Wind I, lease financing arrangement, due 2034 242 252 7.015 16 Alta Wind II, lease financing arrangement, due 2034 191 198 5.696 27 Alta Wind III, lease financing arrangement, due 2034 198 206 6.067 27 Alta Wind IV, lease financing arrangement, due 2034 128 133 5.938 19 Alta Wind V, lease financing arrangement, due 2035 206 213 6.071 30 Alta Realty Investments, due 2031 31 33 7.000 — Alta Wind Asset Management, due 2031 18 19 L+2.375 — Avra Valley, due 2031 57 60 L+1.750 3 Blythe, due 2028 19 21 L+1.625 6 Borrego, due 2025 and 2038 69 72 L+ 2.500/5.650 5 CVSR, due 2037 771 793 2.339 - 3.775 — CVSR Holdco Notes, due 2037 199 — 4.680 13 El Segundo Energy Center, due 2023 443 485 L+1.625 - L+2.250 82 Energy Center Minneapolis, due 2017 and 2025 96 108 5.950 -7.250 — Energy Center Minneapolis Series D Notes, due 2031 125 — 3.550 — Kansas South, due 2031 30 33 L+2.000 4 Laredo Ridge, due 2028 100 104 L+1.875 10 Marsh Landing, due 2017 and 2023 370 418 L+1.750 - L+1.875 22 PFMG and related subsidiaries financing agreement, due 2030 27 29 6.000 — Roadrunner, due 2031 37 40 L+1.625 5 South Trent Wind, due 2020 57 62 L+1.625 10 TA High Desert, due 2020 and 2032 49 52 L+2.500/5.150 8 Tapestry, due 2021 172 181 L+1.625 20 Viento, due 2023 178 189 L+2.750 27 Walnut Creek, due 2023 310 351 L+1.625 41 WCEP Holdings, due 2023 46 46 L+3.000 — Other — 2 various — Subtotal project-level debt 4,314 4,254 Total debt 5,770 5,656 Less current maturities 282 264 Less deferred financing costs 62 63 Total long-term debt $ 5,426 $ 5,329 (a) As of December 31, 2016 , L+ equals 3 month LIBOR plus x%, except for the Alpine term loan, Marsh Landing term loan, Walnut Creek term loan, and NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, where L+ equals 1 month LIBOR plus x% and Kansas South and Viento, where L+ equals 6 month LIBOR plus x%. (b) Net of discount of $16.5 million and $21.5 million as of December 31, 2016 and 2015 , respectively. (c) Net of discount of $10 million and $15 million as of December 31, 2016 and 2015 , respectively. (d) Applicable rate is determined by the Borrower Leverage Ratio, as defined in the credit agreement. 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 arrangement. As of December 31, 2016 , the Company was in compliance with all of the required covenants. NRG Yield Operating LLC 2026 Senior Notes On August 18, 2016, NRG Yield Operating LLC issued $350 million of senior unsecured notes, or the 2026 Senior Notes. The 2026 Senior Notes bear interest at 5.00% and mature on September 15, 2026. Interest on the notes is payable semi-annually on March 15 and September 15 of each year, and interest payments will commence on March 15, 2017. The 2026 Senior Notes are senior unsecured obligations of NRG Yield Operating LLC and are guaranteed by NRG Yield LLC, and by certain of NRG Yield Operating LLC’s wholly owned current and future subsidiaries. A portion of the proceeds of the 2026 Senior Notes were used to repay the Company's revolving credit facility, as described below. NRG Yield Operating LLC 2024 Senior Notes On August 5, 2014, NRG Yield Operating LLC issued $500 million of senior unsecured notes, or the 2024 Senior Notes. The 2024 Senior Notes bear interest at 5.375% and mature in August 2024. Interest on the notes is payable semi-annually on February 15 and August 15 of each year. The 2024 Senior Notes are senior unsecured obligations of NRG Yield Operating LLC and are guaranteed by NRG Yield LLC, and by certain of NRG Yield Operating LLC’s wholly owned current and future subsidiaries. 2020 Convertible Senior Notes The Company has outstanding $287.5 million aggregate principal amount of 3.25% Convertible Senior Notes due 2020, or the 2020 Convertible Notes. The 2020 Convertible Notes are convertible, under certain circumstances, into the Company’s Class C common stock, cash or a combination thereof at an initial conversion price of $27.50 per Class C common share, which is equivalent to a conversion rate of approximately 36.3636 shares of Class C common stock per $1,000 principal amount of notes. Interest on the 2020 Convertible Notes is payable semi-annually in arrears on June 1 and December 1 of each year. The 2020 Convertible Notes mature on June 1, 2020, unless earlier repurchased or converted in accordance with their terms. Prior to the close of business on the business day immediately preceding December 1, 2019, the 2020 Convertible Notes will be convertible only upon the occurrence of certain events and during certain periods, and thereafter, at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. The 2020 Convertible Notes are guaranteed by NRG Yield Operating LLC and NRG Yield LLC. The Company separately accounts for the liability (debt) and equity (conversion option) components of the 2020 Convertible Notes and recognized $23 million as the value for the equity component in 2015 with the offset to debt discount. The debt discount is amortized to interest expense using the effective interest method through June 2020. As of December 31, 2016 , the 2020 Convertible Notes were trading at approximately 97% of their face value, resulting in a total market value of $278 million compared to a carrying value of $271 million . The actual conversion value of the 2020 Convertible Notes is based on the product of the conversion rate and the market price of the Company's Class C common stock, as defined in the Convertible Debt indenture. As of December 31, 2016 , the Company's Class C common stock closed at $15.80 per share, resulting in a pro forma conversion value for the Convertible Notes of approximately $165 million . During the years ended December 31, 2016 and 2015 , the Company recorded the following expense in relation to the 2020 Convertible Notes at the effective rate of 5.10%: (In millions) 2016 2015 Interest expense at 3.25% coupon rate $ 9 $ 5 Debt discount amortization 4 2 Debt issuance costs amortization 1 1 $ 14 $ 8 2019 Convertible Senior Notes The Company has outstanding $345 million aggregate principal amount of 3.50% Convertible Notes due 2019, or the 2019 Convertible Notes. Interest on the 2019 Convertible Notes is payable semi-annually in arrears on February 1 and August 1 of each year. The 2019 Convertible Notes were convertible, under certain circumstances, into the Company’s Class A common stock, cash or a combination thereof at a conversion rate was of approximately 42.9644 shares of Class A common stock per $1,000 principal amount of 2019 Convertible Notes in accordance with the terms of the related indenture. The 2019 Convertible Notes mature on February 1, 2019, unless earlier repurchased or converted in accordance with their terms. Prior to the close of business on the business day immediately preceding August 1, 2018, the 2019 Convertible Notes will be convertible only upon the occurrence of certain events and during certain periods, and thereafter, at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. The 2019 Convertible Notes are guaranteed by NRG Yield Operating LLC and NRG Yield LLC. The Company separately accounts for the liability (debt) and equity (conversion option) components of the 2019 Convertible Notes and recognized $23 million as the value for the equity component in 2014 with the offset to debt discount. The debt discount is amortized to interest expense using the effective interest method through February 2019. As of December 31, 2016 , the 2019 Convertible Notes were trading at approximately 99.6% of their face value, resulting in a total market value of $344 million compared to a carrying value of $335 million . The actual conversion value of the 2019 Convertible Notes is based on the product of the conversion rate and the market price of the Company's Class A common stock, as defined in the Convertible Debt indenture. As of December 31, 2016 , the Company's Class A common stock closed at $15.36 per share, resulting in a pro forma conversion value for the Convertible Notes of approximately $228 million . During the years ended December 31, 2016 and 2015 , the Company recorded the following expense in relation to the 2019 Convertible Notes at the effective rate of 5.00% : (In millions) 2016 2015 Interest expense at 3.5% coupon rate $ 12 $ 12 Debt discount amortization 5 4 Debt issuance costs amortization 2 2 $ 19 $ 18 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility In connection with the Company's initial public offering of Class A common stock in July 2013, as further described in Note 1 , Nature of Business , NRG Yield LLC and NRG Yield Operating LLC entered into a senior secured revolving credit facility, or the Yield Credit Facility, which was amended on June 26, 2015, to, among other things, increase the availability to $495 million . The Company's revolving credit facility can be used for cash or for the issuance of letters of credit. During 2015, the Company borrowed $254 million from the revolving credit facility to finance the acquisition of the November 2015 Drop Down Assets as discussed in Note 3 , Business Acquisitions , as well as fund dividend payments and tax equity contributions. The Company borrowed $60 million from the revolving credit facility and repaid $366 million during the year ended December 31, 2016 . The Company used its pro rata proceeds of $97.5 million from the CVSR Holdco Financing Arrangement in July 2016, a portion of its proceeds from the issuance of the 2026 Senior Notes in August 2015, as well as its cash on hand to repay the outstanding borrowings under the revolving credit facility. As of December 31, 2016 , there were no outstanding borrowings and the Company had $60 million of letters of credit outstanding under the revolving credit facility. Project - level Debt Energy Center Minneapolis LLC Series D Notes On October 31, 2016, NRG Energy Center Minneapolis LLC, a subsidiary of the Company, received proceeds of $125 million from the issuance of 3.55% Series D notes due October 31, 2031, or the Series D Notes, and entered into a shelf facility for the anticipated issuance of an additional $70 million of notes at a 4.80% fixed rate. The Series D Notes will be secured by substantially all of the assets of NRG Energy Center Minneapolis LLC. NRG Thermal LLC has guaranteed the indebtedness and its guarantee is secured by a pledge of the equity interests in all of NRG Thermal LLC’s subsidiaries. NRG Energy Center Minneapolis LLC distributed the proceeds of the Series D Notes to NRG Thermal LLC, which in turn distributed the proceeds to NRG Yield Operating LLC to be utilized for general corporate purposes, including potential acquisitions. CVSR Holdco Notes, due 2037 On July 15, 2016, CVSR Holdco, the indirect owner of the CVSR solar facility, issued $200 million of senior secured notes under the CVSR Holdco Financing Agreement, or 2037 CVSR Holdco Notes, that bear interest at 4.68% and mature on March 31, 2037. Net proceeds were distributed to the Company and NRG based on their respective ownership as of July 15, 2016, and, accordingly, the Company received net proceeds of $97.5 million . As described in Note 3 , Business Acquisitions , on September 1, 2016, the Company acquired the remaining 51.05% of CVSR, and assumed additional debt of $496 million , which represents 51.05% of the CVSR project level debt and 51.05% of the 2037 CVSR Holdco Notes. In connection with the retrospective adjustment of prior periods, as described in Note 1, Nature of Business , the Company now consolidates CVSR and 100% of its debt, consisting of $771 million of project level debt and $200 million of 2037 CVSR Holdco Notes as of September 1, 2016. Avenal On March 18, 2015, Avenal, one of the Company's equity method investments, amended its credit agreement to increase its borrowings by $43 million and to reduce the related interest rate from 6 month LIBOR plus an applicable margin of 2.25% to 6 month LIBOR plus 1.75% from March 18, 2015, through March 17, 2022, 6 month LIBOR plus 2.00% from March 18, 2022, through March 17, 2027, and 6 month LIBOR plus 2.25% from March 18, 2027, through the maturity date. As a result of the credit agreement amendment, the Company received net proceeds of $20 million after fees from its 49.95% ownership in Avenal. Effective September 30, 2015, the Company increased its ownership to 50% by acquiring an additional 0.05% membership interest in Avenal. Lease financing arrangements Alta Wind Holdings (Alta Wind II - V) and Alta I (operating entities) have finance lease obligations issued under lease transactions whereby the respective operating entities sold and leased back undivided interests in specific assets of the project. The sale and related lease transactions are accounted for as financing arrangements as the operating entities have continued involvement with the property. The terms and conditions of each facility lease are substantially similar. Each operating entity makes rental payments as stipulated in the facility lease agreements on a semiannual basis every June 30 and December 30 through the final maturity dates. In addition, the operating entities have a credit agreement with a group of lenders that provides for the issuance of letters of credit to support certain operating and debt service obligations. Certain operations and maintenance, as well as rent reserve requirements are satisfied by letters of credit issued under the NRG Yield Operating agreement. As of December 31, 2016 , $965 million was outstanding under the finance lease obligations, and $119 million of letters of credit were issued under the credit agreement and $23 million were issued under the Yield Credit Facility. Interest Rate Swaps — Project Financings Many of the Company's project subsidiaries entered into interest rate swaps, intended to hedge the risks associated with interest rates on non-recourse project level debt. These swaps amortize in proportion to their respective loans and are floating for fixed where the project subsidiary pays its counterparty the equivalent of a fixed interest payment on a predetermined notional value and will receive quarterly the equivalent of a floating interest payment based on the same notional value. All interest rate swap payments by the project subsidiary and its counterparty are made quarterly and the LIBOR is determined in advance of each interest period. In connection with the acquisition of the Alta Wind Portfolio in 2015, as described in Note 3 , Business Acquisitions , the Company acquired thirty-one additional interest rate swaps, thirty of which were settled during 2015. During 2015, the Company acquired thirty-two additional interest rate swaps in connection with the January 2015 and November 2015 Drop Downs, as described in Note 3 , Business Acquisitions . The following table summarizes the swaps, some of which are forward starting as indicated, related to the Company's project level debt as of December 31, 2016 : % of Principal Fixed Interest Rate Floating Interest Rate Notional Amount at December 31, 2016 (In millions) Effective Date Maturity Date Alpine 85 % 2.744 % 3-Month LIBOR $ 115 various December 31, 2029 Alpine 85 % 2.421 % 3-Month LIBOR 8 June 24, 2014 June 30, 2025 Avra Valley 85 % 2.333 % 3-Month LIBOR 49 November 30, 2012 November 30, 2030 AWAM 100 % 2.47 % 3-Month LIBOR 18 May 22, 2013 May 15, 2031 Blythe 75 % 3.563 % 3-Month LIBOR 14 June 25, 2010 June 25, 2028 Borrego 75 % 1.125 % 3-Month LIBOR 7 April 3, 2013 June 30, 2020 El Segundo 75 % 2.417 % 3-Month LIBOR 330 November 30, 2011 August 31, 2023 Kansas South 75 % 2.368 % 6-Month LIBOR 23 June 28, 2013 December 31, 2030 Laredo Ridge 75 % 2.31 % 3-Month LIBOR 79 March 31, 2011 March 31, 2026 Marsh Landing 75 % 3.244 % 3-Month LIBOR 342 June 28, 2013 June 30, 2023 Roadrunner 75 % 4.313 % 3-Month LIBOR 28 September 30, 2011 December 31, 2029 South Trent 75 % 3.265 % 3-Month LIBOR 43 June 15, 2010 June 14, 2020 South Trent 75 % 4.95 % 3-Month LIBOR 21 June 30, 2020 June 14, 2028 Tapestry 75 % 2.21 % 3-Month LIBOR 155 December 30, 2011 December 21, 2021 Tapestry 50 % 3.57 % 3-Month LIBOR 60 December 21, 2021 December 21, 2029 Viento Funding II 90 % various 6-mo. LIBOR 160 various various Viento Funding II 90 % 4.985 % 6-mo. LIBOR 65 July 11, 2023 June 30, 2028 Walnut Creek Energy 75 % various 3-Month LIBOR 276 June 28, 2013 May 31, 2023 WCEP Holdings 90 % 4.003 % 3-Month LIBOR 46 June 28, 2013 May 31, 2023 Total $ 1,839 Annual Maturities Annual payments based on the maturities of the Company's debt, for the years ending after December 31, 2016 , are as follows: (In millions) 2017 $ 282 2018 292 2019 651 2020 641 2021 439 Thereafter 3,492 Total $ 5,797 Long-Term Debt For a discussion of NRG Yield Inc.’s financing arrangements, see Note 10 , Long-term Debt , to the Company's consolidated financial statements.

Earnings Per Share

Earnings Per Share	12 Months Ended
	Dec. 31, 2016
Earnings (Loss) Per Share Disclosure [Abstract]
Earnings Per Share	Earnings Per Share Basic earnings per common share is computed by dividing net income by the weighted average number of common shares outstanding. Shares issued during the year are weighted for the portion of the year that they were outstanding. Diluted earnings per share is computed in a manner consistent with that of basic earnings per share while giving effect to all potentially dilutive common shares that were outstanding during the period. The number of shares and per share amounts for the prior periods presented below have been retrospectively restated to reflect the Recapitalization as further described in Note 12 , Stockholders' Equity . The reconciliation of the Company's basic and diluted earnings per share is shown in the following table: Year Ended December 31, 2016 Year Ended December 31, 2015 Year Ended December 31, 2014 (In millions, except per share data) (a) Common Class A Common Class C Common Class A Common Class C Common Class A Common Class C Basic and diluted earnings per share attributable to NRG Yield, Inc. common stockholders Net income attributable to NRG Yield, Inc. $ 20 $ 37 $ 14 $ 19 $ 8 $ 8 Weighted average number of common shares outstanding — basic and diluted 35 63 35 49 28 28 Earnings per weighted average common share — basic and diluted $ 0.58 $ 0.58 $ 0.40 $ 0.40 $ 0.30 $ 0.30 (a) Net income attributable to NRG Yield, Inc. and basic and diluted earnings per share might not recalculate due to presenting values in millions rather than whole dollars. The following table summarizes the Company's outstanding equity instruments that are anti-dilutive and were not included in the computation of the Company's diluted earnings per share: Year Ended December 31, 2016 2015 2014 (In millions of shares) 2019 Convertible Notes - Common Class A 15 15 12 2020 Convertible Notes - Common Class C 10 5 —

Stockholders' Equity

Stockholders' Equity	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Attributable to Parent [Abstract]
Stockholders' Equity	Stockholders' Equity On July 22, 2013, in connection with its initial public offering, the Company authorized 500,000,000 shares of Class A common stock, of which 22,511,250 were issued to the public and became outstanding. In return for the issuance of these shares, the Company received $468 million , net of underwriting discounts and commissions of $27 million . In addition, the Company authorized 500,000,000 shares of Class B common stock, of which 42,738,750 were issued to NRG concurrently with the initial public offering and became outstanding. The Company utilized $395 million of the proceeds from the issuance of the Class A common stock to acquire a controlling interest in NRG Yield LLC from NRG. Each share of the Class A common stock and the Class B common stock entitles the holder to one vote on all matters. On July 29, 2014, the Company issued 12,075,000 shares of Class A common stock for net proceeds, after underwriting discount and expenses, of $630 million . The Company utilized the proceeds of the offering to acquire 12,075,000 additional Class A units of NRG Yield LLC. Recapitalization On May 5, 2015, the Company's stockholders approved amendments to the Company's certificate of incorporation that adjusted the Company’s capital structure by creating two new classes of capital stock, Class C common stock and Class D common stock, and distributed shares of Class C and Class D common stock to holders of the Company's outstanding Class A and Class B common stock, respectively, through a stock split. The Recapitalization became effective on May 14, 2015. The Class C common stock and Class D common stock have the same rights and privileges and rank equally, share ratably and are identical in all respects to the shares of Class A common stock and Class B common stock, respectively, as to all matters, except that each share of Class C common stock and Class D common stock is entitled to 1/100th of a vote on all stockholder matters. The par value per share of the Company’s Class A common stock and Class B common stock remains unchanged at $0.01 per share after the effect of the stock split described above. Accordingly, the stock split was accounted for as a stock dividend. The Company recorded a transfer between retained earnings and common stock equal to the par value of each share of Class C common stock and Class D common stock that was issued. The Company also retrospectively adjusted all prior period share and per share amounts in the consolidated financial statements for the effect of the stock dividend, so that all periods are comparable. Class C Common Stock Issuance On June 29, 2015, the Company closed on its offering of 28,198,000 shares of Class C common stock, which included 3,678,000 shares of Class C common stock purchased by the underwriters through the exercise of an over-allotment option. Net proceeds to the Company from the sale of the Class C common stock were $599 million , net of underwriting discounts and commissions of $21 million . The Company utilized the proceeds of the offering to acquire 28,198,000 additional Class C units of NRG Yield LLC and, as a result, it currently owns 53.3% of the economic interests of NRG Yield LLC, with NRG retaining 46.7% of the economic interests of NRG Yield LLC. Dividends to Class A and Class C common stockholders The following table lists the dividends paid on the Company's Class A and Class C common stock during the year ended December 31, 2016 : Fourth Quarter 2016 Third Quarter 2016 Second Quarter 2016 First Quarter 2016 Dividends per Class A share $ 0.25 $ 0.24 $ 0.23 $ 0.225 Dividends per Class C share $ 0.25 $ 0.24 $ 0.23 $ 0.225 Dividends on the Class A and Class C common stock are subject to available capital, market conditions, and compliance with associated laws, regulations and other contractual obligations. The Company expects that, based on current circumstances, comparable cash dividends will continue to be paid in the foreseeable future. On February 15, 2017 , the Company declared a quarterly dividend on its Class A and Class C common stock of $0.26 per share payable on March 15, 2017 , to stockholders of record as of March 1, 2017 . The Company also authorized 10,000,000 shares of preferred stock, par value $0.01 per share. None of the shares of preferred stock have been issued. Distributions to NRG The following table lists the distributions paid to NRG during the year ended December 31, 2016 : Fourth Quarter 2016 Third Quarter 2016 Second Quarter 2016 First Quarter 2016 Distributions per Class B unit $ 0.25 $ 0.24 $ 0.23 $ 0.225 Distributions per Class D unit $ 0.25 $ 0.24 $ 0.23 $ 0.225 The portion of the distributions paid by NRG Yield LLC to NRG is recorded as a reduction to the Company's noncontrolling interest balance. The portion of the distributions paid by NRG Yield LLC to the Company was utilized to fund the dividends to the Class A and Class C common stockholders described above. On February 15, 2017 , NRG Yield LLC declared a quarterly distribution on its Class B and Class D common stock of $0.26 per unit payable to NRG on March 15, 2017 . During 2016, 2015 and 2014, the Company acquired the Drop Down Assets from NRG, as described in Note 3 , Business Acquisitions . The difference between the cash paid and historical value of the CVSR Drop Down of $112 million , as well as $6 million of AOCL, was recorded as a distribution to NRG and reduced the balance of its noncontrolling interest in 2016. The difference between the cash paid and historical value of the January 2015 and November 2015 Drop Down Assets of $109 million , as well as $32 million of AOCL, was recorded as a contribution from NRG and increased the balance of its noncontrolling interest in 2015. The difference between the cash paid and historical value of the June 2014 Drop Down Assets of $113 million was recorded as a distribution to NRG and reduced the balance of its noncontrolling interest in 2014. In addition, as the projects were owned by NRG prior to the Company’s acquisitions, the pre-acquisition earnings of such projects are recorded as attributable to NRG's noncontrolling interest. Prior to the date of acquisition, certain of the projects made distributions to NRG and NRG made contributions into certain projects. These amounts are reflected within the Company’s statement of stockholders’ equity as changes in the noncontrolling interest balance. In addition, NRG maintained a 25% ownership interest in the Class B interests of NRG Wind TE Holdco. This 25% interest is also reflected within the Company’s noncontrolling interest balance.

Segment Reporting

Segment Reporting	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Year ended December 31, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 317 $ 316 $ 195 $ — $ 828 Cost of operations 55 83 139 — 277 Depreciation and amortization 82 133 18 — 233 General and administrative — — — 8 8 Acquisition-related transaction and integration costs — — — 4 4 Operating income (loss) 180 100 38 (12 ) 306 Equity in earnings of unconsolidated affiliates 14 3 — — 17 Other income, net — 5 — 1 6 Loss on debt extinguishment — (1 ) — — (1 ) Interest expense (53 ) (126 ) (7 ) (30 ) (216 ) Income (loss) before income taxes 141 (19 ) 31 (41 ) 112 Income tax expense — — — 4 4 Net Income (Loss) $ 141 $ (19 ) $ 31 $ (45 ) $ 108 Year ended December 31, 2016 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 333 $ 518 $ 170 $ — $ 1,021 Cost of operations 66 126 114 — 306 Depreciation and amortization 80 197 20 — 297 Impairment losses — 183 — — 183 General and administrative — — — 16 16 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 187 12 36 (17 ) 218 Equity in earnings of unconsolidated affiliates 13 24 — — 37 Other income, net 1 2 — — 3 Interest expense (48 ) (141 ) (7 ) (78 ) (274 ) Income (loss) before income taxes 153 (103 ) 29 (95 ) (16 ) Income tax benefit — — — (1 ) (1 ) Net Income (Loss) $ 153 $ (103 ) $ 29 $ (94 ) $ (15 ) Balance Sheet Equity investment in affiliates $ 106 $ 604 $ — $ — $ 710 Capital expenditures (a) 7 2 14 — 23 Total Assets $ 1,993 $ 5,535 $ 426 $ 429 $ 8,383	Year ended December 31, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 336 $ 443 $ 174 $ — $ 953 Cost of operations 59 136 126 — 321 Depreciation and amortization 81 197 19 — 297 General and administrative — — — 12 12 Acquisition-related transaction and integration costs — — — 3 3 Operating income (loss) 196 110 29 (15 ) 320 Equity in earnings of unconsolidated affiliates 14 12 — — 26 Other income, net 1 2 — — 3 Loss on debt extinguishment (7 ) (2 ) — — (9 ) Interest expense (48 ) (147 ) (7 ) (61 ) (263 ) Income (loss) before income taxes 156 (25 ) 22 (76 ) 77 Income tax expense — — — 12 12 Net Income (Loss) $ 156 $ (25 ) $ 22 $ (88 ) $ 65 Balance Sheet Equity investments in affiliates $ 110 $ 587 $ — $ — $ 697 Capital expenditures (a) 4 6 20 — 30 Total Assets $ 2,102 $ 5,970 $ 428 $ 189 $ 8,689
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). The Company generated more than 10% of its revenues from the following customers for the years ended December 31, 2016 , 2015 and 2014 : 2016 2015 2014 Customer Conventional (%) Renewables (%) Conventional (%) Renewables (%) Conventional (%) Renewables (%) SCE 21% 21% 23% 17% 24% 7% PG&E 12% 11% 13% 12% 15% 13% Year ended December 31, 2016 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 333 $ 518 $ 170 $ — $ 1,021 Cost of operations 66 126 114 — 306 Depreciation and amortization 80 197 20 — 297 Impairment losses — 183 — — 183 General and administrative — — — 16 16 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 187 12 36 (17 ) 218 Equity in earnings of unconsolidated affiliates 13 24 — — 37 Other income, net 1 2 — — 3 Interest expense (48 ) (141 ) (7 ) (78 ) (274 ) Income (loss) before income taxes 153 (103 ) 29 (95 ) (16 ) Income tax benefit — — — (1 ) (1 ) Net Income (Loss) $ 153 $ (103 ) $ 29 $ (94 ) $ (15 ) Balance Sheet Equity investment in affiliates $ 106 $ 604 $ — $ — $ 710 Capital expenditures (a) 7 2 14 — 23 Total Assets $ 1,993 $ 5,535 $ 426 $ 429 $ 8,383 (a) Includes accruals. Year ended December 31, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 336 $ 443 $ 174 $ — $ 953 Cost of operations 59 136 126 — 321 Depreciation and amortization 81 197 19 — 297 General and administrative — — — 12 12 Acquisition-related transaction and integration costs — — — 3 3 Operating income (loss) 196 110 29 (15 ) 320 Equity in earnings of unconsolidated affiliates 14 12 — — 26 Other income, net 1 2 — — 3 Loss on debt extinguishment (7 ) (2 ) — — (9 ) Interest expense (48 ) (147 ) (7 ) (61 ) (263 ) Income (loss) before income taxes 156 (25 ) 22 (76 ) 77 Income tax expense — — — 12 12 Net Income (Loss) $ 156 $ (25 ) $ 22 $ (88 ) $ 65 Balance Sheet Equity investments in affiliates $ 110 $ 587 $ — $ — $ 697 Capital expenditures (a) 4 6 20 — 30 Total Assets $ 2,102 $ 5,970 $ 428 $ 189 $ 8,689 (a) Includes accruals. Year ended December 31, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 317 $ 316 $ 195 $ — $ 828 Cost of operations 55 83 139 — 277 Depreciation and amortization 82 133 18 — 233 General and administrative — — — 8 8 Acquisition-related transaction and integration costs — — — 4 4 Operating income (loss) 180 100 38 (12 ) 306 Equity in earnings of unconsolidated affiliates 14 3 — — 17 Other income, net — 5 — 1 6 Loss on debt extinguishment — (1 ) — — (1 ) Interest expense (53 ) (126 ) (7 ) (30 ) (216 ) Income (loss) before income taxes 141 (19 ) 31 (41 ) 112 Income tax expense — — — 4 4 Net Income (Loss) $ 141 $ (19 ) $ 31 $ (45 ) $ 108

Income Taxes

Income Taxes	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Effective Tax Rate The income tax provision consisted of the following amounts: Year Ended December 31, 2016 2015 2014 (In millions, except percentages) Current U.S. Federal $ — $ — $ — State — — — Total — current — — — Deferred U.S. Federal (1 ) 10 2 State — 2 2 Total — deferred (1 ) 12 4 Total income tax (benefit) expense $ (1 ) $ 12 $ 4 Effective tax rate 6.3 % 15.6 % 3.6 % A reconciliation of the U.S. federal statutory rate of 35% to the Company's effective rate is as follows: Year Ended December 31, 2016 2015 2014 (In millions, except percentages) Income Before Income Taxes (16 ) 77 112 Tax at 35% (6 ) 27 39 State taxes, net of federal benefit — 2 1 Investment tax credits (1 ) (1 ) — Impact of non-taxable partnership earnings 5 (15 ) (31 ) Production tax credits, including prior year true-up 4 (4 ) (6 ) Change in state effective tax rate — — 1 Other (3 ) 3 — Income tax (benefit) expense $ (1 ) $ 12 $ 4 Effective income tax rate 6.3 % 15.6 % 3.6 % For the years ended December 31, 2016 , 2015 and 2014 , the overall effective tax rate was different than the statutory rate of 35% primarily due to taxable earnings allocated to NRG resulting from its interest in NRG Yield LLC and production and investment tax credits generated from certain wind and solar assets, respectively. The Company currently owns 53.3% of NRG Yield LLC and consolidates the results due to its controlling interest. The Company records NRG's 46.7% ownership as noncontrolling interest in the financial statements. For tax purposes, NRG Yield LLC is treated as a partnership; therefore, the Company and NRG each record their respective share of taxable income or loss. The temporary differences, which gave rise to the Company's deferred tax assets, consisted of the following: As of December 31, 2016 2015 (In millions) Deferred tax liabilities: Investment in projects $ 3 $ 27 Total deferred tax liabilities 3 27 Deferred tax assets: Production tax credits carryforwards 5 10 Investment tax credits 1 1 U.S. Federal net operating loss carryforwards 226 181 State net operating loss carryforwards 3 5 Total deferred tax assets 235 197 Valuation allowance $ (16 ) $ — Total deferred tax assets, net of valuation allowance $ 219 $ 197 Net deferred noncurrent tax asset $ 216 $ 170 Tax Receivable and Payable As of December 31, 2016 , the Company had a domestic tax receivable of $6 million , which related to federal cash grants for the Borrego project. This amount is fully reserved pending further discussions with the US Treasury Department. Deferred Tax Assets and Valuation Allowance Net deferred tax balance — As of December 31, 2016 and 2015 , NRG recorded a net deferred tax asset of $232 million and $170 million , respectively. The Company believes it is more likely than not that the results of future operations will generate sufficient taxable income which includes the future reversal of existing taxable temporary differences to realize deferred tax assets. The Company considered the profit before tax generated in recent years, as well as projections of future earnings and estimates of taxable income in arriving at this conclusion. The Company believes that $16 million , a deferred tax asset, expected to generate a capital loss, for which there are no existing capital gains or available tax planning strategies to utilize the asset in the future may not be realized, resulting in the recording of a valuation allowance. NOL carryforwards — At December 31, 2016 , the Company had domestic NOLs carryforwards for federal income tax purposes of $226 million and cumulative state NOLs of $3 million tax-effected. Uncertain Tax Positions The Company had no identified uncertain tax positions that require evaluation as of December 31, 2016 .

Related Party Transactions

Related Party Transactions	12 Months Ended
	Dec. 31, 2016
Related Party Transactions [Abstract]
Related Party Transactions Disclosure	Related Party Transactions In addition to the transactions and relationships described elsewhere in the notes to the consolidated financial statements, certain subsidiaries of NRG provide services to the Company's project entities. Amounts due to NRG subsidiaries are recorded as accounts payable — affiliate and amounts due to the Company from NRG subsidiaries are recorded as accounts receivable — affiliate in the Company's balance sheet. The disclosures below summarize the Company's material related party transactions with NRG and its subsidiaries that are included in the Company's operating revenues, operating costs and other income and expense. Power Hedge Contracts by and between Renewable Entities and NRG Texas Power LLC Certain NRG Wind TE Holdco entities, which are subsidiaries in the Renewables segment, entered into power hedge contracts with NRG Texas Power LLC, a subsidiary of NRG, and generated $16 million and $12 million of revenues during the years ended December 31, 2015 and 2014, respectively. Included in the revenues for the years ended December 31, 2015, and 2014, are unrealized losses and gains, respectively, on forward contracts with NRG Texas Power LLC hedging the sale of power from Elbow Creek, extending through the end of 2015, as further described in Note 7 , Accounting for Derivative Instruments and Hedging Activities . Effective October 2015, Elbow Creek entered into a PPA with NRG Power Marketing LLC, or NRG Power Marketing, a wholly-owned subsidiary of NRG, as further described below, and the hedge agreement between Elbow Creek and NRG Texas Power LLC was terminated. PPA by and between Elbow Creek and NRG In October 2015, Elbow Creek, the Company's subsidiary in the Renewables segment, entered into a PPA with NRG Power Marketing for the sale of energy and environmental attributes with the effective date of November 1, 2015, and an expiration date of October 31, 2022. Elbow Creek generated $8 million of revenue during the year ended December 31, 2016 . PPA by and between NRG Energy Center Dover LLC and NRG In February 2016, NRG Energy Center Dover LLC, or NRG Dover, a subsidiary of the Company, entered into a PPA with NRG Power Marketing for the sale of energy and environmental attributes with an effective date of February 1, 2016 and expiration date of December 31, 2018. NRG Dover generated $5 million of revenue during the year ended December 31, 2016 . The agreement in place is in addition to the existing Power Sales and Services Agreement described further below. Power Sales and Services Agreement by and between NRG Energy Center Dover LLC and NRG NRG Dover is party to a Power Sales and Services Agreement with NRG Power Marketing. The agreement is automatically renewed on a month-to-month basis unless terminated by either party upon at least 30 day written notice. Under the agreement, NRG Power Marketing has the exclusive right to (i) manage, market and sell power, (ii) procure fuel and fuel transportation for operation of the Dover generating facility, to include for purposes other than generating power, (iii) procure transmission services required for the sale of power and (iv) procure and market emissions credits for operation of the Dover generating facility. In addition, NRG Power Marketing has the exclusive right and obligation to direct the output from the generating facility, in accordance with and to meet the terms of any power sales contracts executed against the power generation of the Dover facility. Under the agreement, NRG Power Marketing pays NRG Dover gross receipts generated through sales, less costs incurred by NRG Power Marketing related to providing such services as transmission and delivery costs, as well as fuel costs. For the years ended December 31, 2016 , 2015 and 2014 , NRG Dover purchased approximately $1 million , $5 million and $10 million , respectively, of natural gas from NRG Power Marketing under the Power Sales and Services Agreement. Energy Marketing Services Agreement by and between NRG Energy Center Minneapolis LLC and NRG NRG Energy Center Minneapolis LLC, or NRG Minneapolis, a subsidiary of the Company is party to an Energy Marketing Services Agreement with NRG Power Marketing. The agreement commenced in August 2014 and is automatically renewed annually unless terminated by either party upon at least 90 day written notice prior to the end of any term. Under the agreement, NRG Power Marketing will procure fuel and fuel transportation for the operation of the Minneapolis generating facility. For the years ended December 31, 2016 , 2015 and 2014 , NRG Minneapolis purchased approximately $7 million , $8 million and $2 million , respectively, of natural gas from NRG Power Marketing. Operations and Maintenance (O&M) Services Agreements by and between Thermal Entities and NRG On October 1, 2014, NRG entered into Plant O&M Services Agreements with certain wholly-owned subsidiaries of the Company. NRG provides necessary and appropriate services to operate and maintain the subsidiaries' plant operations, businesses and thermal facilities. NRG is to be reimbursed for the provided services, as well as for all reasonable and related expenses and expenditures, and payments to third parties for services and materials rendered to or on behalf of the parties to the agreements. NRG is not entitled to any management fee or mark-up under the agreements. Prior to October 1, 2014, NRG provided the same services to Thermal entities on an informal basis. For each of the years ended December 31, 2016 and 2015 , total fees incurred under the agreements were $29 million . For the year ended December 31, 2014 , total fees incurred were $27 million . There was a balance of $20 million and $29 million due to NRG in accounts payable — affiliate as of December 31, 2016 , and 2015 , respectively. As of December 31, 2016 , $11 million of the balance was recorded in the current liabilities of the consolidated balance sheet and $9 million was recorded in non-current liabilities of the consolidated balance sheet. O&M Services Agreements by and between GenConn and NRG GenConn incurs fees under two O&M agreements with wholly-owned subsidiaries of NRG. The fees incurred under the agreements were $5 million , $4 million and $6 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. O&M Services Agreements by and between El Segundo and NRG El Segundo Operations El Segundo incurs fees under an O&M agreement with NRG El Segundo Operations, Inc., a wholly-owned subsidiary of NRG. Under the O&M agreement, NRG El Segundo Operations, Inc. manages, operates and maintains the El Segundo facility for an initial term of ten years following the commercial operations date. For each of the years ended December 31, 2016 , 2015 and 2014 , the costs incurred under the agreement were approximately $4 million . There was a balance of $1 million due to NRG El Segundo in accounts payable — affiliate as of December 31, 2016 and 2015 . Administrative Services Agreement by and between Marsh Landing and GenOn Energy Services, LLC and related Assignment and Assumption Agreement Marsh Landing was a party to an administrative services agreement with GenOn Energy Services, LLC, a wholly owned subsidiary of NRG, through December 18, 2016. Under the agreement, GenOn Energy Services, LLC provided processing and invoice payment services on behalf of Marsh Landing. Marsh Landing reimbursed GenOn Energy Services, LLC for the amounts it paid. The Company reimbursed costs under this agreement of approximately $14 million for the year ended December 31, 2016, and $13 million for the years ended December 31, 2015 and 2014 , respectively. For the year ended December 31, 2014 , $2 million was capitalized. There was a balance of $1 million and $6 million due to GenOn Energy Services, LLC in accounts payable — affiliate as of December 31, 2016 and 2015 , respectively. Marsh Landing had the right to terminate the agreement for convenience upon thirty days prior written notice. In lieu of a termination of the agreement, Marsh Landing requested that GenOn Energy Services LLC enter into an assignment and assumption agreement with NRG West Coast LLC, a wholly owned subsidiary of NRG. The administrative services agreement was assigned to NRG West Coast LLC on December 19, 2016. Administrative Services Agreement by and between CVSR and NRG CVSR was a party to an administrative services agreement with NRG Energy Services, a wholly-owned subsidiary of NRG, which was subsequently assigned to NRG Renew Operations & Maintenance LLC, or RENOM, on July 15, 2015. The Company reimbursed a total of $4 million and $7 million to NRG Energy Services for the expenses incurred for the years ended December 31, 2015 and 2014, respectively. See below for further discussions of the costs incurred by CVSR under the administrative services agreement with RENOM in 2016. Administrative Services Agreement by and between the Company and NRG Renew Operations & Maintenance LLC Various wholly-owned subsidiaries of the Company in the Renewables segment are party to an administrative services agreement with RENOM, a wholly-owned subsidiary of NRG, which provides O&M services on behalf of these entities. The Company incurred total expenses for these services in the amount of $13 million and $7 million for the years ended December 31, 2016 and 2015 , respectively. There was a balance of $5 million and $1 million due to RENOM as of December 31, 2016 and 2015 , respectively. O&M Services Agreements by and between Walnut Creek and NRG Walnut Creek incurs fees under an O&M agreement with NRG Energy Services LLC, a wholly-owned subsidiary of NRG. Under the O&M agreement, NRG Energy Services LLC manages, operates and maintains the Walnut Creek facility and is reimbursed for the services provided. The Company incurred total expenses for these services in the amount of $3 million for each of the years ended December 31, 2016 and 2015 and $2 million for the year ended December 31, 2014 . Management Services Agreement by and between the Company and NRG NRG provides the Company with various operational, management, and administrative services, which include human resources, accounting, tax, legal, information systems, treasury, and risk management, as set forth in the Management Services Agreement. As of December 31, 2016 , the base management fee was approximately $7.5 million per year, subject to an inflation-based adjustment annually, at an inflation factor based on the year-over-year U.S. consumer price index. The fee is also subject to adjustments following the consummation of future acquisitions and as a result of a change in the scope of services provided under the Management Services Agreement. During the year ended December 31, 2016 , the fee was increased by approximately $0.5 million per year, primarily due to the acquisition of the CVSR Drop Down. In addition to the base management fee, the Company is also responsible for any expenses that are directly incurred and paid for by NRG on behalf of the Company. Costs incurred under this agreement were approximately $10 million , $8 million , and $6 million for the years ended December 31, 2016 , 2015 , and 2014 , respectively. There was a balance of $3 million in accounts payable — affiliate due to NRG as of December 31, 2016 . Administrative Services Agreements by and between Wind TE Holdco LLC and NRG NRG Asset Services LLC, a wholly-owned subsidiary of NRG, provides support services to NRG Wind TE Holdco LLC project entities pursuant to various support services agreements. The agreements provide for administrative and support services and reimbursements of certain insurance, consultant and credit costs. For the years ended December 31, 2016 , 2015 and 2014 , the costs incurred under the agreements were $2 million , $3 million and $1 million , respectively. Accounts Payable to NRG Repowering Holdings LLC During 2013, NRG Repowering Holdings, LLC, a wholly-owned subsidiary of NRG, made payments to BA Leasing BSC, LLC, or BA Leasing, of $18 million , which were expected to be repaid with the proceeds of the cash grant received by BA Leasing with respect to the PFMG DG Solar Projects, in connection with a sale-leaseback arrangement between the PFMG DG Solar Projects and BA Leasing. As of December 31, 2014 , PFMG DG Solar Projects had a corresponding receivable for the reimbursement of the cash grant from BA Leasing and related payable to NRG Repowering Holdings, LLC. In the first quarter of 2014, the PFMG DG Solar Projects received $11 million from BA Leasing and reduced the remaining receivable with an offset to the deferred liability recorded in connection with the sale - leaseback arrangement. The PFMG DG Solar Projects utilized the $11 million to repay NRG Repowering Holdings LLC. There was a balance of $7 million in accounts payable — affiliate as of December 31, 2015 which was settled in October 2016 with an offset to noncontrolling interest in the equity section of the consolidated balance sheet. EPC Agreement by and between NECP and NRG On October 31, 2016, NRG Business Services LLC, a subsidiary of NRG, and NECP, a wholly owned subsidiary of the Company, entered into an EPC agreement for the construction of a 73 MWt district energy system for NECP to provide 150 kpph of steam, 6,750 tons of chilled water and 7.5 MW of emergency backup power service to UPMC Mercy. The initial term of the energy services agreement with UPMC Mercy will be for a period of twenty years from the service commencement date. Pursuant to the terms of the EPC agreement, NECP agreed to pay NRG Business Services LLC $79 million , subject to adjustment based upon certain conditions in the EPC agreement, upon substantial completion of the project. The project is expected to reach COD in the first quarter of 2018. On January 5, 2017, the parties amended the EPC Agreement, based on a customer change order, to increase the capacity of the district energy system from 73 MWt to 80 MWt, which also increased the payment from $79 million to $87 million .

Commitments and Contingencies

Commitments and Contingencies	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies Operating Lease Commitments The Company leases certain facilities and equipment under operating leases, some of which include escalation clauses, expiring on various dates through 2048. The effects of these scheduled rent increases, leasehold incentives, and rent concessions are recognized on a straight-line basis over the lease term unless another systematic and rational allocation basis is more representative of the time pattern in which the leased property is physically employed. Lease expense under operating leases was $15 million , $10 million , and $9 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. Future minimum lease commitments under operating leases for the years ending after December 31, 2016 , are as follows: Period (In millions) 2017 $ 9 2018 9 2019 10 2020 9 2021 9 Thereafter 152 Total $ 198 Gas and Transportation Commitments The Company has entered into contractual arrangements to procure power, fuel and associated transportation services. For the years ended December 31, 2016 , 2015 and 2014 , the Company purchased $32 million , $40 million and $55 million , respectively, under such arrangements. As further described in Note 15 , Related Party Transactions , these balances include intercompany purchases in the amount of $8 million , $13 million , and $12 million , respectively. As of December 31, 2016 , the Company's commitments under such outstanding agreements are estimated as follows: Period (In millions) 2017 $ 13 2018 5 2019 2 2020 3 2021 3 Thereafter 19 Total $ 45 Contingencies 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. 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 v. NRG Yield, Inc. — 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, CA. 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 NRG Yield, Inc.'s June 22, 2015 Class C common stock offering. Plaintiffs seek compensatory damages, rescission, attorney’s fees and costs. On August 3, 2016, the court approved a stipulation entered into by the parties. The stipulation provided that the plaintiffs would file an amended complaint by August 19, 2016, which they did on August 18, 2016. The defendants filed demurrers and a motion challenging jurisdiction on October 18, 2016. On February 24, 2017, the court approved the parties' stipulation which provides the plaintiffs' opposition is due on June 15, 2017 and defendants' reply is due on August 14, 2017. Ahmed v. NRG Energy, Inc. and the NRG Yield Board of Directors — On September 15, 2016, plaintiffs filed a putative class action lawsuit against NRG Energy, Inc., the directors of NRG Yield, Inc., and other parties in the Delaware Chancery Court. The complaint alleges that the defendants breached their respective fiduciary duties with regard to the recapitalization of NRG Yield, Inc. common stock in 2015. The plaintiffs generally seek economic damages, attorney’s fees and injunctive relief. The defendants filed a motion to dismiss the lawsuit on December 21, 2016. Plaintiffs filed their objection to the motion to dismiss on February 15, 2017. Oral argument is scheduled for June 20, 2017. Commitments, Contingencies and Guarantees See Note 14 , Income Taxes , and Note 16 , Commitments and Contingencies , to the Company's consolidated financial statements for a detailed discussion of NRG Yield, Inc.’s commitments and contingencies.

Unaudited Quarterly Financial D

Unaudited Quarterly Financial Data	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Unaudited Quarterly Financial Data	Unaudited Quarterly Data Refer to Note 2 , Summary of Significant Accounting Policies , and Note 3 , Business Acquisitions , for a description of the effect of unusual or infrequently occurring events during the quarterly periods. Summarized unaudited quarterly financial data is as follows: Quarter Ended December 31, September 30, June 30, March 31, 2016 (In millions, except per share data) Operating Revenues $ 232 $ 272 $ 283 $ 234 Operating (Loss) Income (99 ) 117 128 72 Net (Loss) Income (126 ) 47 63 1 Net (Loss) Income Attributable to NRG Yield, Inc. $ (13 ) $ 33 $ 32 $ 5 Weighted average number of Class A common shares outstanding — basic 35 35 35 35 Weighted average number of Class A common shares outstanding — diluted 35 49 49 35 Weighted average number of Class C common shares outstanding — basic 63 63 63 63 Weighted average number of Class C common shares outstanding — diluted 63 73 73 63 (Loss) Earnings per Weighted Average Class A and Class C Common Share - Basic (0.14 ) 0.34 0.33 0.05 (Loss) Earnings per Weighted Average Class A Common Share - Diluted (0.14 ) 0.30 0.29 0.05 (Loss) Earnings per Weighted Average Class C Common Share - Diluted $ (0.14 ) $ 0.32 $ 0.31 $ 0.05 Quarter Ended December 31, September 30, June 30, March 31, 2015 (In millions, except per share data) Operating Revenues $ 224 $ 256 $ 259 $ 214 Operating Income 70 101 99 50 Net Income (Loss) 12 32 42 (21 ) Net Income (Loss) Attributable to NRG Yield, Inc. 11 17 10 (5 ) Weighted average number of Class A common shares outstanding - basic and diluted 35 35 35 35 Weighted average number of Class C common shares outstanding - basic and diluted 63 63 35 35 Earnings (Loss) per Weighted Average Class A and Class C Common Share - Basic and Diluted $ 0.12 $ 0.18 $ 0.15 $ (0.07 )

Yield, Inc. (Parent) Footnotes

Yield, Inc. (Parent) Footnotes (Notes)	12 Months Ended
	Dec. 31, 2016
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Organization, Consolidation and Presentation of Financial Statements Disclosure [Text Block]	Background and Basis of Presentation Background The Company was formed by NRG as a Delaware corporation on December 20, 2012 and closed its initial public offering on July 22, 2013. In connection with its initial public offering, the Company's shares of Class A common stock began trading on the New York Stock Exchange under the symbol “NYLD.” Effective May 14, 2015, the Company completed a stock split in connection with which each outstanding share of Class A common stock was split into one share of Class A common stock and one share of Class C common stock, and each outstanding share of Class B common stock was split into one share of Class B common stock and one share of Class D common stock. The stock split is referred to as the Recapitalization and all references to share or per share amounts in the accompanying consolidated financial statements and applicable disclosures have been retrospectively adjusted to reflect the Recapitalization. Following the Recapitalization, the Company's Class A common stock continued trading on the New York Stock Exchange under the new ticker symbol "NYLD.A" and the Class C common stock began trading under the ticker symbol "NYLD". NRG, through its holdings of Class B common stock and Class D common stock, has a 55.1% voting interest in the Company and receives distributions from NRG Yield LLC through its ownership of Class B units and Class D units. The holders of the Company's issued and outstanding shares of Class A common stock and Class C common stock are entitled to dividends as declared and have 44.9% of the voting power in the Company. The Company is the sole managing member of NRG Yield LLC and operates and controls all of its business and affairs and consolidates the financial results of NRG Yield LLC and its subsidiaries. NRG Yield LLC is a holding company for the companies that directly and indirectly own and operate the Company's business. As of December 31, 2016 , the Company and NRG have 53.3% and 46.7% economic interests in NRG Yield LLC, respectively. As a result of the current ownership of the Class B common stock and Class D common stock, NRG continues at the present time to control the Company, and the Company in turn, as the sole managing member of NRG Yield LLC, controls NRG Yield LLC and its subsidiaries. Basis of Presentation The condensed parent-only company financial statements have been prepared in accordance with Rule 12-04 of Regulation S-X, as the restricted net assets of NRG Yield, Inc.’s subsidiaries exceed 25% of the consolidated net assets of NRG Yield, Inc. The parent's 100% investment in its subsidiaries has been recorded using the equity basis of accounting in the accompanying condensed parent-only financial statements. These statements should be read in conjunction with the consolidated financial statements and notes thereto of NRG Yield, Inc.
Long-term Debt	Long-term Debt The Company's borrowings, including short term and long term portions consisted of the following: December 31, 2016 December 31, 2015 Interest rate % (a) Letters of Credit Outstanding at December 31, 2016 (In millions, except rates) 2026 Senior Notes $ 350 $ — 5.000 2024 Senior Notes 500 500 5.375 2020 Convertible Notes (b) 271 266 3.250 2019 Convertible Notes (c) 335 330 3.500 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 (d) — 306 L+2.500 $ 60 Project-level debt: Alpine, due 2022 145 154 L+1.750 37 Alta Wind I, lease financing arrangement, due 2034 242 252 7.015 16 Alta Wind II, lease financing arrangement, due 2034 191 198 5.696 27 Alta Wind III, lease financing arrangement, due 2034 198 206 6.067 27 Alta Wind IV, lease financing arrangement, due 2034 128 133 5.938 19 Alta Wind V, lease financing arrangement, due 2035 206 213 6.071 30 Alta Realty Investments, due 2031 31 33 7.000 — Alta Wind Asset Management, due 2031 18 19 L+2.375 — Avra Valley, due 2031 57 60 L+1.750 3 Blythe, due 2028 19 21 L+1.625 6 Borrego, due 2025 and 2038 69 72 L+ 2.500/5.650 5 CVSR, due 2037 771 793 2.339 - 3.775 — CVSR Holdco Notes, due 2037 199 — 4.680 13 El Segundo Energy Center, due 2023 443 485 L+1.625 - L+2.250 82 Energy Center Minneapolis, due 2017 and 2025 96 108 5.950 -7.250 — Energy Center Minneapolis Series D Notes, due 2031 125 — 3.550 — Kansas South, due 2031 30 33 L+2.000 4 Laredo Ridge, due 2028 100 104 L+1.875 10 Marsh Landing, due 2017 and 2023 370 418 L+1.750 - L+1.875 22 PFMG and related subsidiaries financing agreement, due 2030 27 29 6.000 — Roadrunner, due 2031 37 40 L+1.625 5 South Trent Wind, due 2020 57 62 L+1.625 10 TA High Desert, due 2020 and 2032 49 52 L+2.500/5.150 8 Tapestry, due 2021 172 181 L+1.625 20 Viento, due 2023 178 189 L+2.750 27 Walnut Creek, due 2023 310 351 L+1.625 41 WCEP Holdings, due 2023 46 46 L+3.000 — Other — 2 various — Subtotal project-level debt 4,314 4,254 Total debt 5,770 5,656 Less current maturities 282 264 Less deferred financing costs 62 63 Total long-term debt $ 5,426 $ 5,329 (a) As of December 31, 2016 , L+ equals 3 month LIBOR plus x%, except for the Alpine term loan, Marsh Landing term loan, Walnut Creek term loan, and NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, where L+ equals 1 month LIBOR plus x% and Kansas South and Viento, where L+ equals 6 month LIBOR plus x%. (b) Net of discount of $16.5 million and $21.5 million as of December 31, 2016 and 2015 , respectively. (c) Net of discount of $10 million and $15 million as of December 31, 2016 and 2015 , respectively. (d) Applicable rate is determined by the Borrower Leverage Ratio, as defined in the credit agreement. 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 arrangement. As of December 31, 2016 , the Company was in compliance with all of the required covenants. NRG Yield Operating LLC 2026 Senior Notes On August 18, 2016, NRG Yield Operating LLC issued $350 million of senior unsecured notes, or the 2026 Senior Notes. The 2026 Senior Notes bear interest at 5.00% and mature on September 15, 2026. Interest on the notes is payable semi-annually on March 15 and September 15 of each year, and interest payments will commence on March 15, 2017. The 2026 Senior Notes are senior unsecured obligations of NRG Yield Operating LLC and are guaranteed by NRG Yield LLC, and by certain of NRG Yield Operating LLC’s wholly owned current and future subsidiaries. A portion of the proceeds of the 2026 Senior Notes were used to repay the Company's revolving credit facility, as described below. NRG Yield Operating LLC 2024 Senior Notes On August 5, 2014, NRG Yield Operating LLC issued $500 million of senior unsecured notes, or the 2024 Senior Notes. The 2024 Senior Notes bear interest at 5.375% and mature in August 2024. Interest on the notes is payable semi-annually on February 15 and August 15 of each year. The 2024 Senior Notes are senior unsecured obligations of NRG Yield Operating LLC and are guaranteed by NRG Yield LLC, and by certain of NRG Yield Operating LLC’s wholly owned current and future subsidiaries. 2020 Convertible Senior Notes The Company has outstanding $287.5 million aggregate principal amount of 3.25% Convertible Senior Notes due 2020, or the 2020 Convertible Notes. The 2020 Convertible Notes are convertible, under certain circumstances, into the Company’s Class C common stock, cash or a combination thereof at an initial conversion price of $27.50 per Class C common share, which is equivalent to a conversion rate of approximately 36.3636 shares of Class C common stock per $1,000 principal amount of notes. Interest on the 2020 Convertible Notes is payable semi-annually in arrears on June 1 and December 1 of each year. The 2020 Convertible Notes mature on June 1, 2020, unless earlier repurchased or converted in accordance with their terms. Prior to the close of business on the business day immediately preceding December 1, 2019, the 2020 Convertible Notes will be convertible only upon the occurrence of certain events and during certain periods, and thereafter, at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. The 2020 Convertible Notes are guaranteed by NRG Yield Operating LLC and NRG Yield LLC. The Company separately accounts for the liability (debt) and equity (conversion option) components of the 2020 Convertible Notes and recognized $23 million as the value for the equity component in 2015 with the offset to debt discount. The debt discount is amortized to interest expense using the effective interest method through June 2020. As of December 31, 2016 , the 2020 Convertible Notes were trading at approximately 97% of their face value, resulting in a total market value of $278 million compared to a carrying value of $271 million . The actual conversion value of the 2020 Convertible Notes is based on the product of the conversion rate and the market price of the Company's Class C common stock, as defined in the Convertible Debt indenture. As of December 31, 2016 , the Company's Class C common stock closed at $15.80 per share, resulting in a pro forma conversion value for the Convertible Notes of approximately $165 million . During the years ended December 31, 2016 and 2015 , the Company recorded the following expense in relation to the 2020 Convertible Notes at the effective rate of 5.10%: (In millions) 2016 2015 Interest expense at 3.25% coupon rate $ 9 $ 5 Debt discount amortization 4 2 Debt issuance costs amortization 1 1 $ 14 $ 8 2019 Convertible Senior Notes The Company has outstanding $345 million aggregate principal amount of 3.50% Convertible Notes due 2019, or the 2019 Convertible Notes. Interest on the 2019 Convertible Notes is payable semi-annually in arrears on February 1 and August 1 of each year. The 2019 Convertible Notes were convertible, under certain circumstances, into the Company’s Class A common stock, cash or a combination thereof at a conversion rate was of approximately 42.9644 shares of Class A common stock per $1,000 principal amount of 2019 Convertible Notes in accordance with the terms of the related indenture. The 2019 Convertible Notes mature on February 1, 2019, unless earlier repurchased or converted in accordance with their terms. Prior to the close of business on the business day immediately preceding August 1, 2018, the 2019 Convertible Notes will be convertible only upon the occurrence of certain events and during certain periods, and thereafter, at any time until the close of business on the second scheduled trading day immediately preceding the maturity date. The 2019 Convertible Notes are guaranteed by NRG Yield Operating LLC and NRG Yield LLC. The Company separately accounts for the liability (debt) and equity (conversion option) components of the 2019 Convertible Notes and recognized $23 million as the value for the equity component in 2014 with the offset to debt discount. The debt discount is amortized to interest expense using the effective interest method through February 2019. As of December 31, 2016 , the 2019 Convertible Notes were trading at approximately 99.6% of their face value, resulting in a total market value of $344 million compared to a carrying value of $335 million . The actual conversion value of the 2019 Convertible Notes is based on the product of the conversion rate and the market price of the Company's Class A common stock, as defined in the Convertible Debt indenture. As of December 31, 2016 , the Company's Class A common stock closed at $15.36 per share, resulting in a pro forma conversion value for the Convertible Notes of approximately $228 million . During the years ended December 31, 2016 and 2015 , the Company recorded the following expense in relation to the 2019 Convertible Notes at the effective rate of 5.00% : (In millions) 2016 2015 Interest expense at 3.5% coupon rate $ 12 $ 12 Debt discount amortization 5 4 Debt issuance costs amortization 2 2 $ 19 $ 18 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility In connection with the Company's initial public offering of Class A common stock in July 2013, as further described in Note 1 , Nature of Business , NRG Yield LLC and NRG Yield Operating LLC entered into a senior secured revolving credit facility, or the Yield Credit Facility, which was amended on June 26, 2015, to, among other things, increase the availability to $495 million . The Company's revolving credit facility can be used for cash or for the issuance of letters of credit. During 2015, the Company borrowed $254 million from the revolving credit facility to finance the acquisition of the November 2015 Drop Down Assets as discussed in Note 3 , Business Acquisitions , as well as fund dividend payments and tax equity contributions. The Company borrowed $60 million from the revolving credit facility and repaid $366 million during the year ended December 31, 2016 . The Company used its pro rata proceeds of $97.5 million from the CVSR Holdco Financing Arrangement in July 2016, a portion of its proceeds from the issuance of the 2026 Senior Notes in August 2015, as well as its cash on hand to repay the outstanding borrowings under the revolving credit facility. As of December 31, 2016 , there were no outstanding borrowings and the Company had $60 million of letters of credit outstanding under the revolving credit facility. Project - level Debt Energy Center Minneapolis LLC Series D Notes On October 31, 2016, NRG Energy Center Minneapolis LLC, a subsidiary of the Company, received proceeds of $125 million from the issuance of 3.55% Series D notes due October 31, 2031, or the Series D Notes, and entered into a shelf facility for the anticipated issuance of an additional $70 million of notes at a 4.80% fixed rate. The Series D Notes will be secured by substantially all of the assets of NRG Energy Center Minneapolis LLC. NRG Thermal LLC has guaranteed the indebtedness and its guarantee is secured by a pledge of the equity interests in all of NRG Thermal LLC’s subsidiaries. NRG Energy Center Minneapolis LLC distributed the proceeds of the Series D Notes to NRG Thermal LLC, which in turn distributed the proceeds to NRG Yield Operating LLC to be utilized for general corporate purposes, including potential acquisitions. CVSR Holdco Notes, due 2037 On July 15, 2016, CVSR Holdco, the indirect owner of the CVSR solar facility, issued $200 million of senior secured notes under the CVSR Holdco Financing Agreement, or 2037 CVSR Holdco Notes, that bear interest at 4.68% and mature on March 31, 2037. Net proceeds were distributed to the Company and NRG based on their respective ownership as of July 15, 2016, and, accordingly, the Company received net proceeds of $97.5 million . As described in Note 3 , Business Acquisitions , on September 1, 2016, the Company acquired the remaining 51.05% of CVSR, and assumed additional debt of $496 million , which represents 51.05% of the CVSR project level debt and 51.05% of the 2037 CVSR Holdco Notes. In connection with the retrospective adjustment of prior periods, as described in Note 1, Nature of Business , the Company now consolidates CVSR and 100% of its debt, consisting of $771 million of project level debt and $200 million of 2037 CVSR Holdco Notes as of September 1, 2016. Avenal On March 18, 2015, Avenal, one of the Company's equity method investments, amended its credit agreement to increase its borrowings by $43 million and to reduce the related interest rate from 6 month LIBOR plus an applicable margin of 2.25% to 6 month LIBOR plus 1.75% from March 18, 2015, through March 17, 2022, 6 month LIBOR plus 2.00% from March 18, 2022, through March 17, 2027, and 6 month LIBOR plus 2.25% from March 18, 2027, through the maturity date. As a result of the credit agreement amendment, the Company received net proceeds of $20 million after fees from its 49.95% ownership in Avenal. Effective September 30, 2015, the Company increased its ownership to 50% by acquiring an additional 0.05% membership interest in Avenal. Lease financing arrangements Alta Wind Holdings (Alta Wind II - V) and Alta I (operating entities) have finance lease obligations issued under lease transactions whereby the respective operating entities sold and leased back undivided interests in specific assets of the project. The sale and related lease transactions are accounted for as financing arrangements as the operating entities have continued involvement with the property. The terms and conditions of each facility lease are substantially similar. Each operating entity makes rental payments as stipulated in the facility lease agreements on a semiannual basis every June 30 and December 30 through the final maturity dates. In addition, the operating entities have a credit agreement with a group of lenders that provides for the issuance of letters of credit to support certain operating and debt service obligations. Certain operations and maintenance, as well as rent reserve requirements are satisfied by letters of credit issued under the NRG Yield Operating agreement. As of December 31, 2016 , $965 million was outstanding under the finance lease obligations, and $119 million of letters of credit were issued under the credit agreement and $23 million were issued under the Yield Credit Facility. Interest Rate Swaps — Project Financings Many of the Company's project subsidiaries entered into interest rate swaps, intended to hedge the risks associated with interest rates on non-recourse project level debt. These swaps amortize in proportion to their respective loans and are floating for fixed where the project subsidiary pays its counterparty the equivalent of a fixed interest payment on a predetermined notional value and will receive quarterly the equivalent of a floating interest payment based on the same notional value. All interest rate swap payments by the project subsidiary and its counterparty are made quarterly and the LIBOR is determined in advance of each interest period. In connection with the acquisition of the Alta Wind Portfolio in 2015, as described in Note 3 , Business Acquisitions , the Company acquired thirty-one additional interest rate swaps, thirty of which were settled during 2015. During 2015, the Company acquired thirty-two additional interest rate swaps in connection with the January 2015 and November 2015 Drop Downs, as described in Note 3 , Business Acquisitions . The following table summarizes the swaps, some of which are forward starting as indicated, related to the Company's project level debt as of December 31, 2016 : % of Principal Fixed Interest Rate Floating Interest Rate Notional Amount at December 31, 2016 (In millions) Effective Date Maturity Date Alpine 85 % 2.744 % 3-Month LIBOR $ 115 various December 31, 2029 Alpine 85 % 2.421 % 3-Month LIBOR 8 June 24, 2014 June 30, 2025 Avra Valley 85 % 2.333 % 3-Month LIBOR 49 November 30, 2012 November 30, 2030 AWAM 100 % 2.47 % 3-Month LIBOR 18 May 22, 2013 May 15, 2031 Blythe 75 % 3.563 % 3-Month LIBOR 14 June 25, 2010 June 25, 2028 Borrego 75 % 1.125 % 3-Month LIBOR 7 April 3, 2013 June 30, 2020 El Segundo 75 % 2.417 % 3-Month LIBOR 330 November 30, 2011 August 31, 2023 Kansas South 75 % 2.368 % 6-Month LIBOR 23 June 28, 2013 December 31, 2030 Laredo Ridge 75 % 2.31 % 3-Month LIBOR 79 March 31, 2011 March 31, 2026 Marsh Landing 75 % 3.244 % 3-Month LIBOR 342 June 28, 2013 June 30, 2023 Roadrunner 75 % 4.313 % 3-Month LIBOR 28 September 30, 2011 December 31, 2029 South Trent 75 % 3.265 % 3-Month LIBOR 43 June 15, 2010 June 14, 2020 South Trent 75 % 4.95 % 3-Month LIBOR 21 June 30, 2020 June 14, 2028 Tapestry 75 % 2.21 % 3-Month LIBOR 155 December 30, 2011 December 21, 2021 Tapestry 50 % 3.57 % 3-Month LIBOR 60 December 21, 2021 December 21, 2029 Viento Funding II 90 % various 6-mo. LIBOR 160 various various Viento Funding II 90 % 4.985 % 6-mo. LIBOR 65 July 11, 2023 June 30, 2028 Walnut Creek Energy 75 % various 3-Month LIBOR 276 June 28, 2013 May 31, 2023 WCEP Holdings 90 % 4.003 % 3-Month LIBOR 46 June 28, 2013 May 31, 2023 Total $ 1,839 Annual Maturities Annual payments based on the maturities of the Company's debt, for the years ending after December 31, 2016 , are as follows: (In millions) 2017 $ 282 2018 292 2019 651 2020 641 2021 439 Thereafter 3,492 Total $ 5,797 Long-Term Debt For a discussion of NRG Yield Inc.’s financing arrangements, see Note 10 , Long-term Debt , to the Company's consolidated financial statements.
Commitments and Contingencies	Commitments and Contingencies Operating Lease Commitments The Company leases certain facilities and equipment under operating leases, some of which include escalation clauses, expiring on various dates through 2048. The effects of these scheduled rent increases, leasehold incentives, and rent concessions are recognized on a straight-line basis over the lease term unless another systematic and rational allocation basis is more representative of the time pattern in which the leased property is physically employed. Lease expense under operating leases was $15 million , $10 million , and $9 million for the years ended December 31, 2016 , 2015 and 2014 , respectively. Future minimum lease commitments under operating leases for the years ending after December 31, 2016 , are as follows: Period (In millions) 2017 $ 9 2018 9 2019 10 2020 9 2021 9 Thereafter 152 Total $ 198 Gas and Transportation Commitments The Company has entered into contractual arrangements to procure power, fuel and associated transportation services. For the years ended December 31, 2016 , 2015 and 2014 , the Company purchased $32 million , $40 million and $55 million , respectively, under such arrangements. As further described in Note 15 , Related Party Transactions , these balances include intercompany purchases in the amount of $8 million , $13 million , and $12 million , respectively. As of December 31, 2016 , the Company's commitments under such outstanding agreements are estimated as follows: Period (In millions) 2017 $ 13 2018 5 2019 2 2020 3 2021 3 Thereafter 19 Total $ 45 Contingencies 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. 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 v. NRG Yield, Inc. — 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, CA. 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 NRG Yield, Inc.'s June 22, 2015 Class C common stock offering. Plaintiffs seek compensatory damages, rescission, attorney’s fees and costs. On August 3, 2016, the court approved a stipulation entered into by the parties. The stipulation provided that the plaintiffs would file an amended complaint by August 19, 2016, which they did on August 18, 2016. The defendants filed demurrers and a motion challenging jurisdiction on October 18, 2016. On February 24, 2017, the court approved the parties' stipulation which provides the plaintiffs' opposition is due on June 15, 2017 and defendants' reply is due on August 14, 2017. Ahmed v. NRG Energy, Inc. and the NRG Yield Board of Directors — On September 15, 2016, plaintiffs filed a putative class action lawsuit against NRG Energy, Inc., the directors of NRG Yield, Inc., and other parties in the Delaware Chancery Court. The complaint alleges that the defendants breached their respective fiduciary duties with regard to the recapitalization of NRG Yield, Inc. common stock in 2015. The plaintiffs generally seek economic damages, attorney’s fees and injunctive relief. The defendants filed a motion to dismiss the lawsuit on December 21, 2016. Plaintiffs filed their objection to the motion to dismiss on February 15, 2017. Oral argument is scheduled for June 20, 2017. Commitments, Contingencies and Guarantees See Note 14 , Income Taxes , and Note 16 , Commitments and Contingencies , to the Company's consolidated financial statements for a detailed discussion of NRG Yield, Inc.’s commitments and contingencies.
Dividends [Text Block]	Dividends Cash distributions paid to NRG Yield, Inc. by its subsidiary, NRG Yield LLC, were $92 million , $69 million , and $41 million for the years ended December 31, 2016 , 2015 , and 2014 , respectively.

Summary of Significant Accoun31

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Policies)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Basis of Presentation	The Company's consolidated financial statements have been prepared in accordance with GAAP. The ASC is the source of authoritative GAAP to be applied by nongovernmental entities. In addition, the rules and interpretative releases of the SEC under authority of federal securities laws are also sources of authoritative GAAP for SEC registrants.
Principles of Consolidation	The consolidated financial statements include the Company's accounts and operations and those of its subsidiaries in which it has a controlling interest. All significant intercompany transactions and balances have been eliminated in consolidation. The usual condition for a controlling financial interest is ownership of a majority of the voting interests of an entity. However, a controlling financial interest may also exist through arrangements that do not involve controlling voting interests. As such, the Company applies the guidance of ASC 810, Consolidations, or ASC 810, to determine when an entity that is insufficiently capitalized or not controlled through its voting interests, referred to as a variable interest entity, or VIE, should be consolidated.
Cash and Cash Equivalents	Cash and Cash Equivalents Cash and cash equivalents include highly liquid investments with an original maturity of three months or less at the time of purchase. Cash and cash equivalents held at project subsidiaries was $105 million and $93 million as of December 31, 2016 and 2015 , respectively.
Restricted Cash	Restricted Cash Restricted cash consists primarily of funds held to satisfy the requirements of certain debt agreements and funds held within the Company's projects that are restricted in their use. Of these funds as of December 31, 2016 , approximately $25 million is designated for current debt service payments, $13 million is designated to fund operating expenses and $37 million is designated for distributions to the Company, with the remaining $90 million restricted for reserves including debt service, performance obligations and other reserves, as well as capital expenditures.
Trade Receivables and Allowance for Doubtful Accounts	Trade Receivables and Allowance for Doubtful Accounts Trade receivables are reported on the balance sheet at the invoiced amount adjusted for any write-offs and the allowance for doubtful accounts. The allowance for doubtful accounts is reviewed periodically based on amounts past due and significance. The allowance for doubtful accounts was immaterial as of December 31, 2016 and 2015 . Notes Receivable Notes receivable consist of receivables related to the financing of required network upgrades. The notes issued with respect to network upgrades will be repaid within a 5 -year period following the date each facility reached commercial operations.
Inventory	Inventory Inventory consists principally of spare parts and fuel oil. Spare parts inventory is valued at weighted average cost, unless evidence indicates that the weighted average cost will not be recovered with a normal profit in the ordinary course of business. Fuel oil inventory is valued at the lower of weighted average cost or market. The Company removes fuel inventories as they are used in the production of steam, chilled water or electricity. Spare parts inventory are removed when they are used for repairs, maintenance or capital projects.
Property, Plant and Equipment	Property, Plant and Equipment Property, plant and equipment are stated at cost or, in the case of third party business acquisitions, fair value; however impairment adjustments are recorded whenever events or changes in circumstances indicate that their carrying values may not be recoverable. See Note 3 , Business Acquisitions , for more information on acquired property, plant and equipment. Significant additions or improvements extending asset lives are capitalized as incurred, while repairs and maintenance that do not improve or extend the life of the respective asset are charged to expense as incurred. Depreciation is computed using the straight-line method over the estimated useful lives. Certain assets and their related accumulated depreciation amounts are adjusted for asset retirements and disposals with the resulting gain or loss included in cost of operations in the consolidated statements of operations.
Asset Impairments	Asset Impairments Long-lived assets that are held and used are reviewed for impairment whenever events or changes in circumstances indicate carrying values may not be recoverable. Such reviews are performed in accordance with ASC 360. An impairment loss is indicated if the total future estimated undiscounted cash flows expected from an asset are less than its carrying value. An impairment charge is measured by the difference between an asset's carrying amount and fair value with the difference recorded in operating costs and expenses in the statements of operations. Fair values are determined by a variety of valuation methods, including appraisals, sales prices of similar assets and present value techniques. For further discussion of the Company's long-lived asset impairments, refer to Note 9 , Asset Impairments . Investments accounted for by the equity method are reviewed for impairment in accordance with ASC 323, Investments-Equity Method and Joint Ventures , which requires that a loss in value of an investment that is an other-than-temporary decline should be recognized. The Company identifies and measures losses in the value of equity method investments based upon a comparison of fair value to carrying value.
Debt Issuance Costs	Debt Issuance Costs Debt issuance costs are capitalized and amortized as interest expense on a basis which approximates the effective interest method over the term of the related debt. Debt issuance costs related to the long term debt are presented as a direct deduction from the carrying amount of the related debt in both the current and prior periods. Debt issuance costs related to the senior secured revolving credit facility line of credit are recorded as a non-current asset on the balance sheet and are amortized over the term of the loan.
Intangible Assets	Intangible Assets Intangible assets represent contractual rights held by the Company. The Company recognizes specifically identifiable intangible assets including power purchase agreements, leasehold improvements, customer relationships, customer contracts, and development rights when specific rights and contracts are acquired. These intangible assets are amortized primarily on a straight-line basis.
Income Taxes	Income Taxes The Company accounts for income taxes using the liability method in accordance with ASC 740, Income Taxes , or ASC 740, which requires that the Company use the asset and liability method of accounting for deferred income taxes and provide deferred income taxes for all significant temporary differences. The Company has two categories of income tax expense or benefit — current and deferred, as follows: • Current income tax expense or benefit consists solely of current taxes payable less applicable tax credits, and • Deferred income tax expense or benefit is the change in the net deferred income tax asset or liability, excluding amounts charged or credited to accumulated other comprehensive income. The Company reports some of its revenues and expenses differently for financial statement purposes than for income tax return purposes, resulting in temporary and permanent differences between the Company's financial statements and income tax returns. The tax effects of such temporary differences are recorded as either deferred income tax assets or deferred income tax liabilities in the Company's consolidated balance sheets. The Company measures its deferred income tax assets and deferred income tax liabilities using income tax rates that are currently in effect. The Company believes it is more likely than not that the results of future operations will generate sufficient taxable income which includes the future reversal of existing taxable temporary differences to realize deferred tax assets, net of valuation allowances. In arriving at this conclusion to utilize projections of future profit before tax in its estimate of future taxable income, the Company considered the profit before tax generated in recent years. A valuation allowance is recorded to reduce the net deferred tax assets to an amount that is more-likely-than-not to be realized. The Company accounts for uncertain tax positions in accordance with ASC 740, which applies to all tax positions related to income taxes. Under ASC 740, tax benefits are recognized when it is more-likely-than-not that a tax position will be sustained upon examination by the authorities. The benefit recognized from a position that has surpassed the more-likely-than-not threshold is the largest amount of benefit that is more than 50% likely to be realized upon settlement. The Company recognizes interest and penalties accrued related to uncertain tax benefits as a component of income tax expense. In accordance with ASC 740 and as discussed further in Note 14 , Income Taxes , changes to existing net deferred tax assets or valuation allowances or changes to uncertain tax benefits, are recorded to income tax expense.
Revenue Recognition	Revenue Recognition Thermal Revenues Steam and chilled water revenue is recognized 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. 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. Power Purchase Agreements, or PPAs The majority of the Company’s revenues are obtained through PPAs or other contractual agreements, which are accounted for as operating leases under ASC 840. 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. Certain of these leases have no minimum lease payments and all of the rental income under these leases is recorded as contingent rent on an actual basis when the electricity is delivered. The contingent rental income recognized in the years ended December 31, 2016 , 2015 , and 2014 was $553 million , $416 million , and $296 million , respectively.
Derivative Financial Instruments	Derivative Financial Instruments The Company accounts for derivative financial instruments under ASC 815, Derivatives and Hedging , or ASC 815, which requires the Company to record all derivatives on the balance sheet at fair value unless they qualify for a NPNS exception. Changes in the fair value of non-hedge derivatives are immediately recognized in earnings. Changes in the fair value of derivatives accounted for as hedges, if elected for hedge accounting, are either: • Recognized in earnings as an offset to the changes in the fair value of the related hedged assets, liabilities and firm commitments; or • Deferred and recorded as a component of accumulated OCI until the hedged transactions occur and are recognized in earnings. The Company's primary derivative instruments are power purchase or sale contracts used to mitigate variability in earnings due to fluctuations in market prices, fuels purchase contracts used to control customer reimbursable fuel cost, and interest rate instruments used to mitigate variability in earnings due to fluctuations in interest rates. On an ongoing basis, the Company assesses the effectiveness of all derivatives that are designated as hedges for accounting purposes in order to determine that each derivative continues to be highly effective in offsetting changes in fair values or cash flows of hedged items. Internal analyses that measure the statistical correlation between the derivative and the associated hedged item determine the effectiveness of such a contract designated as a hedge. If it is determined that the derivative instrument is not highly effective as a hedge, hedge accounting will be discontinued prospectively. In this case, the gain or loss previously deferred in accumulated OCI would be frozen until the underlying hedged item is delivered unless the transaction being hedged is no longer probable of occurring in which case the amount in OCI would be immediately reclassified into earnings. If the derivative instrument is terminated, the effective portion of this derivative deferred in accumulated OCI will be frozen until the underlying hedged item is delivered. Revenues and expenses on contracts that qualify for the NPNS exception are recognized when the underlying physical transaction is delivered. While these contracts are considered derivative financial instruments under ASC 815, they are not recorded at fair value, but on an accrual basis of accounting. If it is determined that a transaction designated as NPNS no longer meets the scope exception, the fair value of the related contract is recorded on the balance sheet and immediately recognized through earnings.
Concentrations of Credit Risk	Concentrations of Credit Risk Financial instruments which potentially subject the Company to concentrations of credit risk consist primarily of accounts receivable, notes receivable and derivative instruments, which are concentrated within entities engaged in the energy and financial industry. These industry concentrations may impact the overall exposure to credit risk, either positively or negatively, in that the customers may be similarly affected by changes in economic, industry or other conditions. In addition, many of the Company's projects have only one customer. However, the Company believes that the credit risk posed by industry concentration is offset by the diversification and creditworthiness of its customer base. See Note 6 , Fair Value of Financial Instruments , for a further discussion of derivative concentrations and Note 13 , Segment Reporting , for concentration of counterparties.
Fair Value of Financial Instruments	Fair Value of Financial Instruments The carrying amount of cash and cash equivalents, restricted cash, accounts receivable, accounts receivable - affiliate, accounts payable, current portion of account payable - affiliate, and accrued expenses and other current liabilities approximate fair value because of the short-term maturity of these instruments. See Note 6 , Fair Value of Financial Instruments , for a further discussion of fair value of financial instruments.
Asset Retirement Obligations	Asset Retirement Obligations Asset retirement obligations, or AROs, are accounted for in accordance with ASC 410-20, Asset Retirement Obligations, or ASC 410-20. Retirement obligations associated with long-lived assets included within the scope of ASC 410-20 are those for which a legal obligation exists under enacted laws, statutes, and written or oral contracts, including obligations arising under the doctrine of promissory estoppel, and for which the timing and/or method of settlement may be conditional on a future event. ASC 410-20 requires an entity to recognize the fair value of a liability for an ARO in the period in which it is incurred and a reasonable estimate of fair value can be made. Upon initial recognition of a liability for an ARO, the asset retirement cost is capitalized by increasing the carrying amount of the related long-lived asset by the same amount. Over time, the liability is accreted to its future value, while the capitalized cost is depreciated over the useful life of the related asset. The Company's AROs are primarily related to the future dismantlement of equipment on leased property and environmental obligations related to site closures and fuel storage facilities. The Company records AROs as part of other non-current liabilities on its balance sheet. The following table represents the balance of ARO obligations as of December 31, 2016 and 2015 , along with the additions and accretion related to the Company's ARO obligations for the year ended December 31, 2016 : (In millions) Balance as of December 31, 2015 $ 43 Revisions in estimates for current obligations 2 Accretion — expense 3 Balance as of December 31, 2016 $ 48
Guarantees	Guarantees The Company enters into various contracts that include indemnification and guarantee provisions as a routine part of its business activities. Examples of these contracts include operation and maintenance agreements, service agreements, commercial sales arrangements and other types of contractual agreements with vendors and other third parties, as well as affiliates. These contracts generally indemnify the counterparty for tax, environmental liability, litigation and other matters, as well as breaches of representations, warranties and covenants set forth in these agreements. Because many of the guarantees and indemnities the Company issues to third parties and affiliates do not limit the amount or duration of its obligations to perform under them, there exists a risk that the Company may have obligations in excess of the amounts agreed upon in the contracts mentioned above. For those guarantees and indemnities that do not limit the liability exposure, the Company may not be able to estimate what the liability would be, until a claim is made for payment or performance, due to the contingent nature of these contracts.
Investments Accounted for by the Equity Method	Investments Accounted for by the Equity Method The Company has investments in various energy projects accounted for by the equity method, four of which are VIEs, where the Company is not a primary beneficiary, and two of which are owned by a subsidiary that is consolidated as a VIE, as described in Note 5 , Investments Accounted for by the Equity Method and Variable Interest Entities . The equity method of accounting is applied to these investments in affiliates because the ownership structure prevents the Company from exercising a controlling influence over the operating and financial policies of the projects. Under this method, equity in pre-tax income or losses of the investments is reflected as equity in earnings of unconsolidated affiliates. Distributions from equity method investments that represent earnings on the Company's investment are included within cash flows from operating activities and distributions from equity method investments that represent a return of the Company's investment are included within cash flows from investing activities.
Leases	Sale Leaseback Arrangements The Company is party to sale-leaseback arrangements that provide for the sale of certain assets to a third party and simultaneous leaseback to the Company. In accordance with ASC 840-40, Sale-Leaseback Transactions , if the seller-lessee retains, through the leaseback, substantially all of the benefits and risks incident to the ownership of the property sold, the sale-leaseback transaction is accounted for as a financing arrangement. An example of this type of continuing involvement would include an option to repurchase the assets or the buyer-lessor having the option to sell the assets back to the Company. This provision is included in most of the Company’s sale-leaseback arrangements. As such, the Company accounts for these arrangements as financings. Under the financing method, the Company does not recognize as income any of the sale proceeds received from the lessor that contractually constitutes payment to acquire the assets subject to these arrangements. Instead, the sale proceeds received are accounted for as financing obligations and leaseback payments made by the Company are allocated between interest expense and a reduction to the financing obligation. Interest on the financing obligation is calculated using the Company’s incremental borrowing rate at the inception of the arrangement on the outstanding financing obligation. Judgment is required to determine the appropriate borrowing rate for the arrangement and in determining any gain or loss on the transaction that would be recorded either at the end of or over the lease term.
Business Combinations	Business Combinations The Company accounts for its business combinations in accordance with ASC 805, Business Combinations, or ASC 805. For third party acquisitions, ASC 805 requires an acquirer to recognize and measure in its financial statements the identifiable assets acquired, the liabilities assumed, and any noncontrolling interest in the acquiree at fair value at the acquisition date. It also recognizes and measures the goodwill acquired or a gain from a bargain purchase in the business combination and determines what information to disclose to enable users of an entity's financial statements to evaluate the nature and financial effects of the business combination. In addition, transaction costs are expensed as incurred. For acquisitions that relate to entities under common control, ASC 805 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 of from the date the entities were under common control (if later than the beginning of the financial statement period). The difference between the cash paid and historical value of the entities' equity is recorded as a distribution/contribution from/to NRG with the offset to noncontrolling interest. Transaction costs are expensed as incurred.
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 amount of assets and liabilities and disclosures of contingent assets and liabilities as of the date of the consolidated financial statements. They also impact the reported amount of net earnings during the reporting period. Actual results could be different from these estimates. In recording transactions and balances resulting from business operations, the Company uses estimates based on the best information available. Estimates are used for such items as plant depreciable lives, tax provisions, uncollectible accounts, environmental liabilities, acquisition accounting and legal costs incurred in connection with recorded loss contingencies, among others. In addition, estimates are used to test long-lived assets for impairment and to determine the fair value of impaired assets. As better information becomes available or actual amounts are determinable, the recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates.
Tax Equity Arrangements	Tax Equity Arrangements Certain portions of the Company’s noncontrolling interests in subsidiaries represent third-party interests in the net assets under certain tax equity arrangements, which are consolidated by the Company, that have been entered into to finance the cost of wind facilities eligible for certain tax credits. Additionally, certain portions of the Company’s investments in unconsolidated affiliates reflect the Company’s interests in tax equity arrangements, that are not consolidated by the Company, that have been entered into to finance the cost of distributed solar energy systems under operating leases or PPAs eligible for certain tax credits. The Company has determined that the provisions in the contractual agreements of these structures represent substantive profit sharing arrangements. Further, the Company has determined that the appropriate methodology for calculating the noncontrolling interest and investment in unconsolidated affiliates that reflects the substantive profit sharing arrangements is a balance sheet approach utilizing the hypothetical liquidation at book value, or HLBV, method. Under the HLBV method, the amounts reported as noncontrolling interests and investment in unconsolidated affiliates represent the amounts the investors to the tax equity arrangements would hypothetically receive at each balance sheet date under the liquidation provisions of the contractual agreements, assuming the net assets of the funding structures were liquidated at their recorded amounts determined in accordance with GAAP. The investors’ interests in the results of operations of the funding structures are determined as the difference in noncontrolling interests and investment in unconsolidated affiliates at the start and end of each reporting period, after taking into account any capital transactions between the structures and the funds’ investors. The calculations utilized to apply the HLBV method include estimated calculations of taxable income or losses for each reporting period.
Reclassifications	Reclassifications Certain prior year amounts have been reclassified for comparative purposes.
Recent Accounting Developments	Recent Accounting Developments ASU 2016-18 — In November 2016, the FASB issued ASU No. 2016-18, Statement of Cash Flows (Topic 230) , Restricted Cash, or ASU No. 2016-18. The amendments of ASU No. 2016-18 were issued to address the diversity in classification and presentation of changes in restricted cash and restricted cash equivalents on the statement of cash flows which is currently not addressed under Topic 230. The amendments of ASU No. 2016-18 would require an entity to include amounts generally described as restricted cash and restricted cash equivalents with cash and cash equivalents when reconciling the beginning of period and end of period total amounts on the statement of cash flows. The amendments of ASU No. 2016-18 are effective for annual reporting periods beginning after December 15, 2017, and interim periods within those annual periods. Early adoption is permitted and the adoption of ASU No. 2016-18 should be applied retrospectively. The Company is currently evaluating the impact of the standard on the Company’s statement of cash flows. ASU 2016-16 — In October 2016, the FASB issued ASU No. 2016-16, Income Taxes (Topic 740) , Intra-Entity Transfers of Assets Other Than Inventory, or ASU No. 2016-16. The amendments of ASU No. 2016-16 were issued to improve the accounting for the income tax consequences of intra-entity transfers of assets other than inventory. Current GAAP prohibits the recognition of current and deferred income taxes for an intra-entity asset transfer until the asset has been sold to an outside party which has resulted in diversity in practice and increased complexity within financial reporting. The amendments of ASU No. 2016-16 would require an entity to recognize the income tax consequences of an intra-entity transfer of an asset other than inventory when the transfer occurs and do not require new disclosure requirements. The amendments of ASU No. 2016-16 are effective for annual reporting periods beginning after December 15, 2017, and interim periods within those annual periods. Early adoption is permitted and the adoption of ASU No. 2016-16 should be applied on a modified retrospective basis through a cumulative-effect adjustment directly to retained earnings as of the beginning of the period of adoption. The Company is currently evaluating the impact of the standard on the Company’s results of operations, cash flows and financial position. ASU 2016-15 — In August 2016, the FASB issued ASU No. 2016-15, Statement of Cash Flows (Topic 230) , Classification of Certain Cash Receipts and Cash Payments, or ASU No. 2016-15. The amendments of ASU No. 2016-15 were issued to address eight specific cash flow issues for which stakeholders have indicated to the FASB that a diversity in practice existed in how entities were presenting and classifying these items in the statement of cash flows. The issues addressed by ASU No. 2016-15 include but are not limited to the classification of debt prepayment and debt extinguishment costs, payments made for contingent consideration for a business combination, proceeds from the settlement of insurance proceeds, distributions received from equity method investees and separately identifiable cash flows and the application of the predominance principle. The amendments of ASU No. 2016-15 are effective for public entities for fiscal years beginning after December 15, 2017 and interim periods in those fiscal years. Early adoption is permitted, including adoption in an interim fiscal period with all amendments adopted in the same period. The adoption of ASU No. 2016-15 is required to be applied retrospectively. The Company is currently evaluating the impact of the standard on the Company's statement of cash flows. ASU 2016-07 — In March 2016, the FASB issued ASU No. 2016-07, Investments - Equity Method and Joint Ventures (Topic 323), or ASU No. 2016-07. The amendments of ASU No. 2016-07 eliminate the requirement that when an investment qualifies for use of the equity method as a result of an increase in the level of ownership interest or degree of influence, an investor must adjust the investment, results of operations, and retained earnings retroactively on a step-by-step basis as if the equity method had been in effect during all previous periods that the investment had been held. The amendments require that the equity method investor add the cost of acquiring the additional interest in the investee to the current basis of the investor's previously held interest and adopt the equity method of accounting with no retroactive adjustment to the investment. In addition, ASU No. 2016-07 requires that an entity that has an available-for-sale equity security that becomes qualified for the equity method of accounting recognize through earnings the unrealized holding gain or loss in accumulated other comprehensive income at the date the investment becomes qualified for use of the equity method. The Company adopted this standard effective January 1, 2017. The adoption of ASU No. 2016-07 is required to be applied prospectively. The Company does not expect the standard to have a material impact on its results of operations, cash flows and financial position. ASU 2016-02 — In 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 expects to adopt the standard effective January 1, 2019 utilizing the required modified retrospective approach for the earliest period presented. The Company 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. As this review is still in process, it is currently not practicable to quantify the impact of adopting the ASU at this time. ASU 2016-01 — In January 2016, the FASB issued ASU No. 2016-01, Financial Instruments - Overall (Subtopic 825-10): Recognition and Measurement of Financial Assets and Financial Liabilities , or ASU No. 2016-01. The amendments of ASU No. 2016-01 eliminate available-for-sale classification of equity investments and require that equity investments (except those accounted for under the equity method of accounting, or those that result in consolidation of the investee) to be generally measured at fair value with changes in fair value recognized in net income. Further, the amendments require that financial assets and financial liabilities to be presented separately in the notes to the financial statements, grouped by measurement category and form of financial asset. The guidance in ASU No. 2016-01 is effective for financial statements issued for fiscal years beginning after December 15, 2017, and interim periods within those annual periods. The Company is currently evaluating the impact of the standard on the Company's results of operations, cash flows and financial position. ASU 2015-16 — In September 2015, the FASB issued ASU No. 2015-16, Business Combinations (Topic 805): Simplifying the Accounting for Measurement-Period Adjustments , or ASU No. 2015-16. The amendments of ASU No. 2015-16 require that an acquirer recognize measurement period adjustments to the provisional amounts recognized in a business combination in the reporting period during which the adjustments are determined. Additionally, the amendments of ASU No. 2015-16 require the acquirer to record in the same period's financial statements the effect on earnings of changes in depreciation, amortization or other income effects, if any, as a result of the measurement period adjustment, calculated as if the accounting had been completed at the acquisition date as well as disclosing on either the face of the income statement or in the notes the portion of the amount recorded in current period earnings that would have been recorded in previous reporting periods. The guidance in ASU No. 2015-16 is effective for financial statements issued for fiscal years beginning after December 15, 2015, and interim periods within those fiscal years. The amendments should be applied prospectively. The Company adopted ASU No. 2015-16 for the year ended December 31, 2016, and the adoption did not have a material impact on the Company's results of operations, cash flows and financial position. ASU 2014-09 — In May 2014, the FASB issued ASU No. 2014-09, Revenue from Contracts with Customers (Topic 606), or ASU No. 2014-09, which was further amended through various updates issued by the FASB thereafter. The amendments of ASU No. 2014-09 completed the joint effort between the FASB and the IASB, to develop a common revenue standard for GAAP and IFRS, and to improve financial reporting. The guidance under Topic 606 provides that an entity should recognize revenue to depict the transfer of goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled to in exchange for the goods or services provided and establishes a five step model to be applied by an entity in evaluating its contracts with customers. The Company expects to adopt the standard effective January 1, 2018 and apply the guidance retrospectively to contracts at the date of adoption. The Company will recognize the cumulative effect of applying Topic 606 at the date of initial application, as prescribed under the modified retrospective transition method. The Company also expects to elect the practical expedient available under Topic 606 for measuring progress toward complete satisfaction of a performance obligation and for disclosure requirements of remaining performance obligations. The practical expedient allows an entity to recognize revenue in the amount to which the entity has the right to invoice such that the entity has a right to the consideration in an amount that corresponds directly with the value to the customer for performance completed to date by the entity. The majority of the Company's revenues are obtained through PPAs, which are currently accounted for as operating leases. In connection with the implementation of Topic 842, as described above, the Company expects to elect certain of the practical expedients permitted, including the expedient that permits the Company to retain its existing lease assessment and classification. As leases are excluded from the scope of Topic 606, the Company expects the standard to have an immaterial impact on the Company's results of operations, cash flows and financial position; however, the Company continues to assess the impact in connection with its plan of adoption.

Segment Reporting Segment Repor

Segment Reporting Segment Reporting (Policies)	12 Months Ended
	Dec. 31, 2016
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)	12 Months Ended
	Dec. 31, 2016
Nature of Business Disclosure [Abstract]
IPO of NRG Yield	The following table represents the structure of the Company as of December 31, 2016 :
The Company's operating assets are comprised of the following projects:	he 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 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 CVSR 100 % 250 Pacific Gas and Electric 2038 Desert Sunlight 250 25 % 63 Southern California Edison 2035 Desert Sunlight 300 25 % 75 Pacific Gas and Electric 2040 Kansas South 100 % 20 Pacific Gas and Electric 2033 Roadrunner 100 % 20 El Paso Electric 2031 TA High Desert 100 % 20 Southern California Edison 2033 610 Distributed Solar AZ DG Solar Projects 100 % 5 Various 2025 - 2033 PFMG DG Solar Projects 51 % 4 Various 2032 9 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) 74.3 % 16 Corn Belt Power Cooperative 2027 Elbow Creek (b) 75 % 92 NRG Power Marketing LLC 2022 Elkhorn Ridge (b) 50.3 % 41 Nebraska Public Power District 2029 Forward (b) 75 % 22 Constellation NewEnergy, Inc. 2017 Goat Wind (b) 74.9 % 113 Dow Pipeline Company 2025 Hardin (b) 74.3 % 11 Interstate Power and Light Company 2027 Laredo Ridge 100 % 80 Nebraska Public Power District 2031 Lookout (b) 75 % 29 Southern Maryland Electric Cooperative 2030 Odin (b) 74.9 % 15 Missouri River Energy Services 2028 Pinnacle 100 % 55 Maryland Department of General Services and University System of Maryland 2031 San Juan Mesa (b) 56.3 % 68 Southwestern Public Service Company 2025 Sleeping Bear (b) 75 % 71 Public Service Company of Oklahoma 2032 South Trent 100 % 101 AEP Energy Partners 2029 Spanish Fork (b) 75 % 14 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 Projects Percentage Ownership Net Capacity (MW) (a) Offtake Counterparty Expiration Taloga 100 % 130 Oklahoma Gas & Electric 2031 Wildorado (b) 74.9 % 121 Southwestern Public Service Company 2027 1,999 Thermal Thermal equivalent MWt (c) 100 % 1,319 Various Various NRG Energy Center Dover LLC 100 % 103 NRG Power Marketing LLC 2018 Thermal generation 100 % 20 Various Various 1,442 Total net capacity (excluding equivalent MWt) (d) 4,686 (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 December 31, 2016 . (b) Projects are part of tax equity arrangements. (c) 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. (d) NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Summary of Significant Accoun34

Summary of Significant Accounting Policies Summary of Significant Accounting Policies (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting Policies [Abstract]
Schedule of Asset Retirement Obligations [Table Text Block]	The following table represents the balance of ARO obligations as of December 31, 2016 and 2015 , along with the additions and accretion related to the Company's ARO obligations for the year ended December 31, 2016 : (In millions) Balance as of December 31, 2015 $ 43 Revisions in estimates for current obligations 2 Accretion — expense 3 Balance as of December 31, 2016 $ 48

Business Acquisitions Business

Business Acquisitions Business Acquisitions (Tables)	12 Months Ended
	Dec. 31, 2016
CVSR [Member]
Business Acquisition [Line Items]
Schedule of Recognized Identified Assets Acquired and Liabilities Assumed [Table Text Block]	The following is the summary of historical net liabilities assumed in connection with the CVSR Drop Down as of September 1, 2016: CVSR (In millions) Current assets $ 95 Property, plant and equipment 826 Non-current assets 13 Total assets 934 Debt (a) 966 Other current and non-current liabilities 12 Total liabilities 978 Net liabilities assumed (44 ) Accumulated other comprehensive loss (25 ) Historical net liabilities assumed $ (19 ) (a) Net of deferred financing costs of $5 million .
Alta Wind Portfolio [Member]
Business Acquisition [Line Items]
Business Acquisition, Purchase Price [Table Text Block]	The purchase price of $923 million was allocated as follows: Acquisition Date Fair Value at December 31, 2014 Measurement period adjustments Revised Acquisition Date Assets (In millions) Cash $ 22 $ — $ 22 Current and non-current assets 49 (2 ) 47 Property, plant and equipment 1,304 6 1,310 Intangible assets 1,177 (6 ) 1,171 Total assets acquired 2,552 (2 ) 2,550 Liabilities Debt 1,591 — 1,591 Current and non-current liabilities 38 (2 ) 36 Total liabilities assumed 1,629 (2 ) 1,627 Net assets acquired $ 923 $ — $ 923

Property, Plant and Equipment (

Property, Plant and Equipment (Tables)	12 Months Ended
	Dec. 31, 2016
Property, Plant and Equipment [Abstract]
Schedule of Property, Plant and Equipment	The Company’s major classes of property, plant, and equipment were as follows: December 31, 2016 December 31, 2015 Depreciable Lives (In millions) Facilities and equipment $ 6,215 $ 6,480 2 - 40 Years Land and improvements 171 171 Construction in progress (a) 25 9 Total property, plant and equipment 6,411 6,660 Accumulated depreciation (951 ) (782 ) Net property, plant and equipment $ 5,460 $ 5,878

Investments Accounted for by 37

Investments Accounted for by the Equity Method and Variable Interest Entities (Tables)	12 Months Ended
	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Schedule of Variable Interest Entities [Table Text Block]	Summarized financial information for the Company's consolidated VIEs consisted of the following as of December 31, 2016 : (In millions) NRG Wind TE Holdco Alta TE Holdco Spring Canyon Other current and non-current assets $ 193 $ 17 $ 4 Property, plant and equipment 441 461 100 Intangible assets 2 274 — Total assets 636 752 104 Current and non-current liabilities 209 9 6 Total liabilities 209 9 6 Noncontrolling interest 139 107 67 Net assets less noncontrolling interests $ 288 $ 636 $ 31
Schedule of Equity Method Investments [Line Items]
Summarized financial information of equity method investment	The following table summarizes the Company's equity method investments as of December 31, 2016 : Name Economic Interest Investment Balance (In millions) Desert Sunlight 25% $282 GenConn (a) 50% 106 Elkhorn Ridge (b) 50.3% 85 San Juan Mesa (b) 56.3% 74 NRG DGPV Holdco 1 LLC (c) 95% 75 NRG DGPV Holdco 2 LLC (c) 95% 24 NRG RPV Holdco 1 LLC (c) 95% 71 Avenal 50% (7) Total equity investments in affiliates $710 (a) GenConn is a variable interest entity. (b) San Juan Mesa and Elkhorn Ridge are part of the Wind TE Holdco tax equity structure, as described below. San Juan Mesa and Elkhorn Ridge are owned 75% and 66.7% , respectively, by Wind TE Holdco. The Company owns 75% of the Class B interests in Wind TE Holdco. (c) Economic interest based on cash to be distributed. NRG DGPV Holdco 1 LLC, NRG DGPV Holdco 2 LLC, and NRG RPV Holdco 1 LLC are tax equity structures and VIEs. The related allocations are described below.
Entities that are not consolidated [Member]
Schedule of Equity Method Investments [Line Items]
Summarized financial information of equity method investment	The following tables present summarized financial information for the Company's significant equity method investments: Year Ended December 31, 2016 2015 2014 Income Statement Data: (In millions) GenConn Operating revenues $ 72 $ 78 $ 82 Operating income 38 40 40 Net income 26 28 28 Desert Sunlight Operating revenues $ 211 $ 206 Operating income 129 124 Net income 80 73 As of December 31, 2016 2015 Balance Sheet Data: (In millions) GenConn Current assets $ 36 $ 36 Non-current assets 389 416 Current liabilities 16 16 Non-current liabilities 196 215 Desert Sunlight Current assets $ 281 $ 310 Non-current assets 1,401 1,435 Current liabilities 64 82 Non-current liabilities 1,043 1,086

Fair Value of Financial Instr38

Fair Value of Financial Instruments (Tables)	12 Months Ended
	Dec. 31, 2016
Fair Value Disclosures [Abstract]
Estimated carrying values and fair values of the Company's recorded financial instruments	The estimated carrying amounts and fair values of the Company’s recorded financial instruments not carried at fair market value are as follows: As of December 31, 2016 As of December 31, 2015 Carrying Amount Fair Value Carrying Amount Fair Value (In millions) Assets: Notes receivable, including current portion 30 30 47 47 Liabilities: Long-term debt, including current portion 5,770 5,769 5,656 5,538
Fair Value, Option, Quantitative Disclosures [Table Text Block]	The following table presents the level within the fair value hierarchy for long-term debt, including current portion as of December 31, 2016 and 2015 : As of December 31, 2016 As of December 31, 2015 Level 2 Level 3 Level 2 Level 3 (In millions) Long-term debt, including current portion $ 1,455 $ 4,314 $ 978 $ 4,560
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis [Table Text Block]	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 December 31, 2016 As of December 31, 2016 As of December 31, 2015 Fair Value (a) Fair Value (a) Fair Value (a) (In millions) Level 1 Level 2 Level 2 Derivative assets: Commodity contracts $ 1 $ 1 $ — Interest rate contracts — 1 — Total assets $ 1 $ 2 — Derivative liabilities: Commodity contracts $ — $ 1 2 Interest rate contracts — 71 98 Total liabilities $ — $ 72 $ 100 (a) There were no assets or liabilities classified as Level 1 as of December 31, 2015 . There were no assets or liabilities classified Level 3 as of December 31, 2016 and 2015 .

Accounting for Derivative Ins39

Accounting for Derivative Instruments and Hedging Activities (Tables)	12 Months Ended
	Dec. 31, 2016
Accounting for Derivative Instruments and Hedging Activities Disclosure [Abstract]
Net notional volume buy/(sell) of NRG Yield's open derivative transactions broken out by commodity	The following table summarizes the net notional volume buy/(sell) of the Company's open derivative transactions broken out by commodity as of December 31, 2016 and 2015 : Total Volume December 31, 2016 December 31, 2015 Commodity Units (In millions) Natural Gas MMBtu 3 4 Interest Dollars $ 1,839 $ 1,991
Fair value within the derivative instrument valuation on the balance sheets	The following table summarizes the fair value within the derivative instrument valuation on the balance sheet: Fair Value Derivative Assets Derivative Liabilities December 31, 2016 December 31, 2016 December 31, 2015 (In millions) Derivatives Designated as Cash Flow Hedges: Interest rate contracts current $ — $ 26 $ 34 Interest rate contracts long-term 1 39 56 Total Derivatives Designated as Cash Flow Hedges 1 65 90 Derivatives Not Designated as Cash Flow Hedges : Interest rate contracts current — 2 3 Interest rate contracts long-term — 4 5 Commodity contracts current 2 1 2 Total Derivatives Not Designated as Cash Flow Hedges 2 7 10 Total Derivatives $ 3 $ 72 $ 100
Offsetting of derivatives by counterparty master agreement level and collateral received or paid	The following table summarizes the offsetting of derivatives by counterparty master agreement level as of December 31, 2016 : Gross Amounts Not Offset in the Statement of Financial Position As of December 31, 2016 Gross Amounts of Recognized Assets/Liabilities Derivative Instruments Net Amount Commodity contracts: (In millions) Derivative assets $ 2 $ — $ 2 Derivative liabilities (1 ) — (1 ) Total commodity contracts 1 — 1 Interest rate contracts: Derivative assets 1 (1 ) — Derivative liabilities (71 ) 1 (70 ) Total interest rate contracts (70 ) — (70 ) Total derivative instruments $ (69 ) $ — $ (69 )
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, net of tax: Year ended December 31, 2016 2015 2014 (In millions) Accumulated OCL beginning balance $ (83 ) $ (76 ) $ (16 ) Reclassified from accumulated OCL to income due to realization of previously deferred amounts 13 14 14 Mark-to-market of cash flow hedge accounting contracts — (21 ) (74 ) Accumulated OCL ending balance, net of income tax benefit of $16, $16 and $6, respectively $ (70 ) $ (83 ) $ (76 ) Accumulated OCL attributable to noncontrolling interests (42 ) (56 ) (67 ) Accumulated OCL attributable to NRG Yield, Inc. $ (28 ) $ (27 ) $ (9 ) Losses expected to be realized from OCL during the next 12 months, net of income tax benefit of $3 $ 16 Amounts reclassified from accumulated OCL into income and amounts recognized in income from the ineffective portion of cash flow hedges are recorded to interest expense. There was no ineffectiveness for the years ended December 31, 2016 , 2015 and 2014 . Accounting guidelines require a high degree of correlation between the derivative and the hedged item throughout the period in order to qualify as a cash flow hedge. As of December 31, 2016 , the Company's regression analysis for Viento Funding II interest rate swaps, while positively correlated, did not meet the required threshold for cash flow hedge accounting. As a result, the Company de-designated the Viento Funding II cash flow hedges as of December 31, 2016 , and will prospectively mark these derivatives to market through the income statement.

Intangible Assets (Tables)

Intangible Assets (Tables)	12 Months Ended
	Dec. 31, 2016
Goodwill and Intangible Assets Disclosure [Abstract]
Summary of the components of the Company's intangible assets subject to amortization	The following tables summarize the components of intangible assets subject to amortization: Year ended December 31, 2016 PPAs Leasehold Rights Customer Customer Contracts Emission Allowances Development Other Total (In millions) January 1, 2016 $ 1,264 $ 86 $ 66 $ 15 $ 15 $ 3 $ 6 $ 1,455 Other — — — — (6 ) — — (6 ) December 31, 2016 1,264 86 66 15 9 3 6 1,449 Less accumulated amortization (138 ) (9 ) (4 ) (7 ) (2 ) (1 ) (2 ) (163 ) Net carrying amount $ 1,126 $ 77 $ 62 $ 8 $ 7 $ 2 $ 4 $ 1,286 Year ended December 31, 2015 PPAs Leasehold Rights Customer Relationships Customer Contracts Emission Allowances Development Rights Other Total (In millions) January 1, 2015 $ 1,270 $ 86 $ 66 $ 15 $ 16 $ 3 $ 6 $ 1,462 Other (6 ) — — — (1 ) — — (7 ) December 31, 2015 1,264 86 66 15 15 3 6 1,455 Less accumulated amortization (75 ) (5 ) (3 ) (6 ) (1 ) (1 ) (2 ) (93 ) Net carrying amount $ 1,189 $ 81 $ 63 $ 9 $ 14 $ 2 $ 4 $ 1,362

Long-term Debt (Tables)

Long-term Debt (Tables)	12 Months Ended
	Dec. 31, 2016
Debt Disclosure [Abstract]
Schedule of Effective Interest Rate [Table Text Block]	During the years ended December 31, 2016 and 2015 , the Company recorded the following expense in relation to the 2019 Convertible Notes at the effective rate of 5.00% : (In millions) 2016 2015 Interest expense at 3.5% coupon rate $ 12 $ 12 Debt discount amortization 5 4 Debt issuance costs amortization 2 2 $ 19 $ 18
Schedule of long-term debt	The Company's borrowings, including short term and long term portions consisted of the following: December 31, 2016 December 31, 2015 Interest rate % (a) Letters of Credit Outstanding at December 31, 2016 (In millions, except rates) 2026 Senior Notes $ 350 $ — 5.000 2024 Senior Notes 500 500 5.375 2020 Convertible Notes (b) 271 266 3.250 2019 Convertible Notes (c) 335 330 3.500 NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 (d) — 306 L+2.500 $ 60 Project-level debt: Alpine, due 2022 145 154 L+1.750 37 Alta Wind I, lease financing arrangement, due 2034 242 252 7.015 16 Alta Wind II, lease financing arrangement, due 2034 191 198 5.696 27 Alta Wind III, lease financing arrangement, due 2034 198 206 6.067 27 Alta Wind IV, lease financing arrangement, due 2034 128 133 5.938 19 Alta Wind V, lease financing arrangement, due 2035 206 213 6.071 30 Alta Realty Investments, due 2031 31 33 7.000 — Alta Wind Asset Management, due 2031 18 19 L+2.375 — Avra Valley, due 2031 57 60 L+1.750 3 Blythe, due 2028 19 21 L+1.625 6 Borrego, due 2025 and 2038 69 72 L+ 2.500/5.650 5 CVSR, due 2037 771 793 2.339 - 3.775 — CVSR Holdco Notes, due 2037 199 — 4.680 13 El Segundo Energy Center, due 2023 443 485 L+1.625 - L+2.250 82 Energy Center Minneapolis, due 2017 and 2025 96 108 5.950 -7.250 — Energy Center Minneapolis Series D Notes, due 2031 125 — 3.550 — Kansas South, due 2031 30 33 L+2.000 4 Laredo Ridge, due 2028 100 104 L+1.875 10 Marsh Landing, due 2017 and 2023 370 418 L+1.750 - L+1.875 22 PFMG and related subsidiaries financing agreement, due 2030 27 29 6.000 — Roadrunner, due 2031 37 40 L+1.625 5 South Trent Wind, due 2020 57 62 L+1.625 10 TA High Desert, due 2020 and 2032 49 52 L+2.500/5.150 8 Tapestry, due 2021 172 181 L+1.625 20 Viento, due 2023 178 189 L+2.750 27 Walnut Creek, due 2023 310 351 L+1.625 41 WCEP Holdings, due 2023 46 46 L+3.000 — Other — 2 various — Subtotal project-level debt 4,314 4,254 Total debt 5,770 5,656 Less current maturities 282 264 Less deferred financing costs 62 63 Total long-term debt $ 5,426 $ 5,329 (a)
Summary of swaps related to the Company's project level debt	he following table summarizes the swaps, some of which are forward starting as indicated, related to the Company's project level debt as of December 31, 2016 : % of Principal Fixed Interest Rate Floating Interest Rate Notional Amount at December 31, 2016 (In millions) Effective Date Maturity Date Alpine 85 % 2.744 % 3-Month LIBOR $ 115 various December 31, 2029 Alpine 85 % 2.421 % 3-Month LIBOR 8 June 24, 2014 June 30, 2025 Avra Valley 85 % 2.333 % 3-Month LIBOR 49 November 30, 2012 November 30, 2030 AWAM 100 % 2.47 % 3-Month LIBOR 18 May 22, 2013 May 15, 2031 Blythe 75 % 3.563 % 3-Month LIBOR 14 June 25, 2010 June 25, 2028 Borrego 75 % 1.125 % 3-Month LIBOR 7 April 3, 2013 June 30, 2020 El Segundo 75 % 2.417 % 3-Month LIBOR 330 November 30, 2011 August 31, 2023 Kansas South 75 % 2.368 % 6-Month LIBOR 23 June 28, 2013 December 31, 2030 Laredo Ridge 75 % 2.31 % 3-Month LIBOR 79 March 31, 2011 March 31, 2026 Marsh Landing 75 % 3.244 % 3-Month LIBOR 342 June 28, 2013 June 30, 2023 Roadrunner 75 % 4.313 % 3-Month LIBOR 28 September 30, 2011 December 31, 2029 South Trent 75 % 3.265 % 3-Month LIBOR 43 June 15, 2010 June 14, 2020 South Trent 75 % 4.95 % 3-Month LIBOR 21 June 30, 2020 June 14, 2028 Tapestry 75 % 2.21 % 3-Month LIBOR 155 December 30, 2011 December 21, 2021 Tapestry 50 % 3.57 % 3-Month LIBOR 60 December 21, 2021 December 21, 2029 Viento Funding II 90 % various 6-mo. LIBOR 160 various various Viento Funding II 90 % 4.985 % 6-mo. LIBOR 65 July 11, 2023 June 30, 2028 Walnut Creek Energy 75 % various 3-Month LIBOR 276 June 28, 2013 May 31, 2023 WCEP Holdings 90 % 4.003 % 3-Month LIBOR 46 June 28, 2013 May 31, 2023 Total $ 1,839
Schedule of annual payments based on the maturities of NRG Yield's debt	nnual payments based on the maturities of the Company's debt, for the years ending after December 31, 2016 , are as follows: (In millions) 2017 $ 282 2018 292 2019 651 2020 641 2021 439 Thereafter 3,492 Total $ 5,797

Earnings Per Share (Tables)

Earnings Per Share (Tables)	12 Months Ended
	Dec. 31, 2016
Earnings (Loss) Per Share Disclosure [Abstract]
Reconciliation of NRG's basic earnings per share to diluted earnings per share	The reconciliation of the Company's basic and diluted earnings per share is shown in the following table: Year Ended December 31, 2016 Year Ended December 31, 2015 Year Ended December 31, 2014 (In millions, except per share data) (a) Common Class A Common Class C Common Class A Common Class C Common Class A Common Class C Basic and diluted earnings per share attributable to NRG Yield, Inc. common stockholders Net income attributable to NRG Yield, Inc. $ 20 $ 37 $ 14 $ 19 $ 8 $ 8 Weighted average number of common shares outstanding — basic and diluted 35 63 35 49 28 28 Earnings per weighted average common share — basic and diluted $ 0.58 $ 0.58 $ 0.40 $ 0.40 $ 0.30 $ 0.30

Stockholders' Equity Stockholde

Stockholders' Equity Stockholders' Equity (Tables)	12 Months Ended
	Dec. 31, 2016
Stockholders' Equity Attributable to Parent [Abstract]
Schedule of Distributions Paid [Table Text Block]	The following table lists the distributions paid to NRG during the year ended December 31, 2016 : Fourth Quarter 2016 Third Quarter 2016 Second Quarter 2016 First Quarter 2016 Distributions per Class B unit $ 0.25 $ 0.24 $ 0.23 $ 0.225 Distributions per Class D unit $ 0.25 $ 0.24 $ 0.23 $ 0.225
Schedule of Dividends Paid [Table Text Block]	The following table lists the dividends paid on the Company's Class A and Class C common stock during the year ended December 31, 2016 : Fourth Quarter 2016 Third Quarter 2016 Second Quarter 2016 First Quarter 2016 Dividends per Class A share $ 0.25 $ 0.24 $ 0.23 $ 0.225 Dividends per Class C share $ 0.25 $ 0.24 $ 0.23 $ 0.225

Segment Reporting (Tables)

Segment Reporting (Tables)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Segment Reporting [Abstract]
Schedule of Revenue by Major Customers by Reporting Segments [Table Text Block]	The Company generated more than 10% of its revenues from the following customers for the years ended December 31, 2016 , 2015 and 2014 : 2016 2015 2014 Customer Conventional (%) Renewables (%) Conventional (%) Renewables (%) Conventional (%) Renewables (%) SCE 21% 21% 23% 17% 24% 7% PG&E 12% 11% 13% 12% 15% 13%
Schedule of Segment Reporting Information, by Segment	Year ended December 31, 2014 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 317 $ 316 $ 195 $ — $ 828 Cost of operations 55 83 139 — 277 Depreciation and amortization 82 133 18 — 233 General and administrative — — — 8 8 Acquisition-related transaction and integration costs — — — 4 4 Operating income (loss) 180 100 38 (12 ) 306 Equity in earnings of unconsolidated affiliates 14 3 — — 17 Other income, net — 5 — 1 6 Loss on debt extinguishment — (1 ) — — (1 ) Interest expense (53 ) (126 ) (7 ) (30 ) (216 ) Income (loss) before income taxes 141 (19 ) 31 (41 ) 112 Income tax expense — — — 4 4 Net Income (Loss) $ 141 $ (19 ) $ 31 $ (45 ) $ 108 Year ended December 31, 2016 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 333 $ 518 $ 170 $ — $ 1,021 Cost of operations 66 126 114 — 306 Depreciation and amortization 80 197 20 — 297 Impairment losses — 183 — — 183 General and administrative — — — 16 16 Acquisition-related transaction and integration costs — — — 1 1 Operating income (loss) 187 12 36 (17 ) 218 Equity in earnings of unconsolidated affiliates 13 24 — — 37 Other income, net 1 2 — — 3 Interest expense (48 ) (141 ) (7 ) (78 ) (274 ) Income (loss) before income taxes 153 (103 ) 29 (95 ) (16 ) Income tax benefit — — — (1 ) (1 ) Net Income (Loss) $ 153 $ (103 ) $ 29 $ (94 ) $ (15 ) Balance Sheet Equity investment in affiliates $ 106 $ 604 $ — $ — $ 710 Capital expenditures (a) 7 2 14 — 23 Total Assets $ 1,993 $ 5,535 $ 426 $ 429 $ 8,383	Year ended December 31, 2015 (In millions) Conventional Generation Renewables Thermal Corporate Total Operating revenues $ 336 $ 443 $ 174 $ — $ 953 Cost of operations 59 136 126 — 321 Depreciation and amortization 81 197 19 — 297 General and administrative — — — 12 12 Acquisition-related transaction and integration costs — — — 3 3 Operating income (loss) 196 110 29 (15 ) 320 Equity in earnings of unconsolidated affiliates 14 12 — — 26 Other income, net 1 2 — — 3 Loss on debt extinguishment (7 ) (2 ) — — (9 ) Interest expense (48 ) (147 ) (7 ) (61 ) (263 ) Income (loss) before income taxes 156 (25 ) 22 (76 ) 77 Income tax expense — — — 12 12 Net Income (Loss) $ 156 $ (25 ) $ 22 $ (88 ) $ 65 Balance Sheet Equity investments in affiliates $ 110 $ 587 $ — $ — $ 697 Capital expenditures (a) 4 6 20 — 30 Total Assets $ 2,102 $ 5,970 $ 428 $ 189 $ 8,689

Income Taxes (Tables)

Income Taxes (Tables)	12 Months Ended
	Dec. 31, 2016
Income Tax Disclosure [Abstract]
Income tax provision from continuing operations	The income tax provision consisted of the following amounts: Year Ended December 31, 2016 2015 2014 (In millions, except percentages) Current U.S. Federal $ — $ — $ — State — — — Total — current — — — Deferred U.S. Federal (1 ) 10 2 State — 2 2 Total — deferred (1 ) 12 4 Total income tax (benefit) expense $ (1 ) $ 12 $ 4 Effective tax rate 6.3 % 15.6 % 3.6 %
Reconciliation of the U.S. federal statutory rate to the Company's effective rate	A reconciliation of the U.S. federal statutory rate of 35% to the Company's effective rate is as follows: Year Ended December 31, 2016 2015 2014 (In millions, except percentages) Income Before Income Taxes (16 ) 77 112 Tax at 35% (6 ) 27 39 State taxes, net of federal benefit — 2 1 Investment tax credits (1 ) (1 ) — Impact of non-taxable partnership earnings 5 (15 ) (31 ) Production tax credits, including prior year true-up 4 (4 ) (6 ) Change in state effective tax rate — — 1 Other (3 ) 3 — Income tax (benefit) expense $ (1 ) $ 12 $ 4 Effective income tax rate 6.3 % 15.6 % 3.6 %
Company's deferred tax assets and liabilities	The temporary differences, which gave rise to the Company's deferred tax assets, consisted of the following: As of December 31, 2016 2015 (In millions) Deferred tax liabilities: Investment in projects $ 3 $ 27 Total deferred tax liabilities 3 27 Deferred tax assets: Production tax credits carryforwards 5 10 Investment tax credits 1 1 U.S. Federal net operating loss carryforwards 226 181 State net operating loss carryforwards 3 5 Total deferred tax assets 235 197 Valuation allowance $ (16 ) $ — Total deferred tax assets, net of valuation allowance $ 219 $ 197 Net deferred noncurrent tax asset $ 216 $ 170

Commitments and Contingencies (

Commitments and Contingencies (Tables)	12 Months Ended
	Dec. 31, 2016
Commitments and Contingencies Disclosure [Abstract]
Long-term Purchase Commitment [Table Text Block]	As of December 31, 2016 , the Company's commitments under such outstanding agreements are estimated as follows: Period (In millions) 2017 $ 13 2018 5 2019 2 2020 3 2021 3 Thereafter 19 Total $ 45
Future minimum lease commitments under operating leases	Future minimum lease commitments under operating leases for the years ending after December 31, 2016 , are as follows: Period (In millions) 2017 $ 9 2018 9 2019 10 2020 9 2021 9 Thereafter 152 Total $ 198

Unaudited Quarterly Financial47

Unaudited Quarterly Financial Data (Tables)	12 Months Ended
	Dec. 31, 2016
Quarterly Financial Information Disclosure [Abstract]
Summary of Unaudited Quarterly Financial Data	Summarized unaudited quarterly financial data is as follows: Quarter Ended December 31, September 30, June 30, March 31, 2016 (In millions, except per share data) Operating Revenues $ 232 $ 272 $ 283 $ 234 Operating (Loss) Income (99 ) 117 128 72 Net (Loss) Income (126 ) 47 63 1 Net (Loss) Income Attributable to NRG Yield, Inc. $ (13 ) $ 33 $ 32 $ 5 Weighted average number of Class A common shares outstanding — basic 35 35 35 35 Weighted average number of Class A common shares outstanding — diluted 35 49 49 35 Weighted average number of Class C common shares outstanding — basic 63 63 63 63 Weighted average number of Class C common shares outstanding — diluted 63 73 73 63 (Loss) Earnings per Weighted Average Class A and Class C Common Share - Basic (0.14 ) 0.34 0.33 0.05 (Loss) Earnings per Weighted Average Class A Common Share - Diluted (0.14 ) 0.30 0.29 0.05 (Loss) Earnings per Weighted Average Class C Common Share - Diluted $ (0.14 ) $ 0.32 $ 0.31 $ 0.05 Quarter Ended December 31, September 30, June 30, March 31, 2015 (In millions, except per share data) Operating Revenues $ 224 $ 256 $ 259 $ 214 Operating Income 70 101 99 50 Net Income (Loss) 12 32 42 (21 ) Net Income (Loss) Attributable to NRG Yield, Inc. 11 17 10 (5 ) Weighted average number of Class A common shares outstanding - basic and diluted 35 35 35 35 Weighted average number of Class C common shares outstanding - basic and diluted 63 63 35 35 Earnings (Loss) per Weighted Average Class A and Class C Common Share - Basic and Diluted $ 0.12 $ 0.18 $ 0.15 $ (0.07 )

Nature of Business (Details)

Nature of Business (Details) - MW		Jul. 29, 2014	Dec. 31, 2016	Aug. 31, 2016	Nov. 02, 2015	Jun. 30, 2015
Nature of Business
Power Generation Capacity, Megawatts	[1],[2]		4,686
Megawatts Thermal Equivalent, Available Under right-to-use Provisions			134
Power Generation Capacity, Megawatts, including portion attributable to noncontrolling interest	[1],[2]		4,692
Conventional Generation [Member]
Nature of Business
Power Generation Capacity, Megawatts	[1]		1,945
Utility-Scale Solar
Nature of Business
Power Generation Capacity, Megawatts	[1]		610
Distributed Solar
Nature of Business
Power Generation Capacity, Megawatts	[1]		9
Wind Farms [Member]
Nature of Business
Power Generation Capacity, Megawatts	[1]		1,999
Thermal [Member]
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		1,442
Steam and Chilled Water Capacity, Megawatts Thermal Equivalent	[1],[3]		1,319
NRG Energy Center Dover [Member]
Nature of Business
Percentage of Ownership			100.00%
Thermal [Member] | Thermal [Member]
Nature of Business
Power Generation Capacity, Megawatts	[1]		20
NRG Yield LLC | NRG Yield, Inc. [Member]
Nature of Business
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Voting Interest			44.90%
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest		53.30%	53.30%
NRG Yield LLC | NRG
Nature of Business
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Voting Interest			55.10%
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest		46.70%	46.70%
GenConn Middletown [Member] | 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
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%			49.95%
Power Generation Capacity, Megawatts	[1]		23
Avra Valley [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		26
NRG Solar Blythe LLC [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		21
Borrego [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		26
NRG Solar Roadrunner LLC [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		20
CVSR [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		250
RE Kansas South [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
Desert Sunlight [Member] | Utility-Scale Solar
Nature of Business
Percentage of Ownership			25.00%
AZ DG Solar Projects | Distributed Solar
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		5
PFMG DG Solar Projects | Distributed Solar
Nature of Business
Percentage of Ownership			51.00%
Power Generation Capacity, Megawatts	[1]		4
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	[3]		100.00%
Power Generation Capacity, Megawatts	[1],[3]		137
Alta XI [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership	[3]		100.00%
Power Generation Capacity, Megawatts	[1],[3]		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			75.00%
Power Generation Capacity, Megawatts	[1],[4]		14
Laredo Ridge [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		80
Lookout [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			75.00%
Power Generation Capacity, Megawatts	[1],[4]		29
Odin Wind Farm [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			74.90%
Power Generation Capacity, Megawatts	[1],[4]		15
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
San Juan Mesa Wind Project, LLC [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			56.30%
Power Generation Capacity, Megawatts	[1],[4]		68
Sleeping Bear [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			75.00%
Power Generation Capacity, Megawatts	[1],[4]		71
Buffalo Bear [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			100.00%
Power Generation Capacity, Megawatts	[1]		19
Crosswinds [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			74.30%
Power Generation Capacity, Megawatts	[1],[4]		16
Elbow Creek [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			75.00%
Power Generation Capacity, Megawatts	[1],[4]		92
Forward [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			75.00%
Power Generation Capacity, Megawatts	[1],[4]		22
Goat Wind [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			74.90%
Power Generation Capacity, Megawatts	[1],[4]		113
Elkhorn Ridge Wind, LLC [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			50.30%
Power Generation Capacity, Megawatts	[1],[4]		41
Hardin [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			74.30%
Power Generation Capacity, Megawatts	[1],[4]		11
Spring Canyon [Member] | Wind Farms [Member]
Nature of Business
Power Generation Capacity, Megawatts attributed to noncontrolling interest			6
Spring Canyon II [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			90.10%
Power Generation Capacity, Megawatts	[1],[4]		29
Spring Canyon III [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			90.10%
Power Generation Capacity, Megawatts	[1],[4]		25
Wildorado [Member] | Wind Farms [Member]
Nature of Business
Percentage of Ownership			74.90%
Power Generation Capacity, Megawatts	[1],[4]		121
NRG Energy Center Dover [Member] | Thermal [Member]
Nature of Business
Power Generation Capacity, Megawatts	[1]		103
CVSR [Member]
Nature of Business
Equity Method Investment, Ownership Percentage				48.95%
November 2015 Drop Down Assets [Member] | Wind Farms [Member]
Nature of Business
Power Generation Capacity, Megawatts					814
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
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.
[3]	c) 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.
[4]	(b) Projects are part of tax equity arrangements.

Summary of Significant Accoun49

Summary of Significant Accounting Policies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Summary of Significant Accounting Policies [Line Items]
Asset Retirement Obligation, Accretion Expense	$ 3
Income Taxes, Threshold Percentage	50.00%
Contingent Rental Income Associated with PPAs	$ 553	$ 416	$ 296
Asset Retirement Obligation	48	43
Deferred Tax Assets, Net	216	170
Proceeds from renewable energy grants	0	0	$ 422
Asset Retirement Obligation, Revision of Estimate	2
Project Level Subsidiaries [Member]
Summary of Significant Accounting Policies [Line Items]
Other Cash Equivalents, at Carrying Value	105	$ 93
Long-Term Debt, Current [Member]
Summary of Significant Accounting Policies [Line Items]
Restricted Cash and Cash Equivalents	25
Operating Expense [Member]
Summary of Significant Accounting Policies [Line Items]
Restricted Cash and Cash Equivalents	13
Cash Distribution [Member]
Summary of Significant Accounting Policies [Line Items]
Restricted Cash and Cash Equivalents	37
Reserves [Member]
Summary of Significant Accounting Policies [Line Items]
Restricted Cash and Cash Equivalents	$ 90

Business Acquisitions Busines50

Business Acquisitions Business Acquisitions - CVSR (Details) - USD ($) $ in Millions	Sep. 02, 2016	Sep. 30, 2016	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Sep. 01, 2016	Aug. 31, 2016
Business Acquisition [Line Items]
Long-term Debt			$ 5,770	$ 5,656
Current assets			645	416
Property, Plant and Equipment, Net			5,460	5,878
Assets			8,383	8,689
Liabilities			6,013	5,951
Accumulated other comprehensive loss			(28)	(27)	$ (9)
Debt Issuance Costs, Net			62	63
Acquisition-related transaction and integration costs			1	3	$ 4
CVSR [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage							48.95%
Business Acquisition, Percentage of Voting Interests Acquired						51.05%
Payments to Acquire Businesses, Gross	$ 78.5
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt						$ 496
Business Combination, Indemnification Assets, Amount as of Acquisition Date						67
Current assets						95
Property, Plant and Equipment, Net						826
Non-current assets						13
Assets						934
Long-term Debt and Capital Lease Obligations, Including Current Maturities						966
Other Liabilities						12
Liabilities						978
Net Assets						44
Accumulated other comprehensive loss						(25)
Net Assets, excluding Accumulated Other Comprehensive Income (Loss)						(19)
Debt Issuance Costs, Net						5
Acquisition-related transaction and integration costs			1
Business Combination, Pro Forma Information, Revenue of Acquiree since Acquisition Date, Actual		$ 22
Business Combination, Pro Forma Information, Earnings or Loss of Acquiree since Acquisition Date, Actual		$ 2
CVSR Financing Agreement [Member]
Business Acquisition [Line Items]
Long-term Debt			771	793
CVSR Financing Agreement [Member] | CVSR [Member]
Business Acquisition [Line Items]
Long-term Debt						771
CVSR Holdco due 2037 [Member]
Business Acquisition [Line Items]
Long-term Debt			$ 199	$ 0
CVSR Holdco due 2037 [Member] | CVSR [Member]
Business Acquisition [Line Items]
Long-term Debt						$ 200

Business Acquisitions Busines51

Business Acquisitions Business Acquisitions - November 2015 Drop Down Assets (Details)		Feb. 19, 2016USD ($)	Nov. 03, 2015USD ($)	Dec. 31, 2016MW	Nov. 02, 2015USD ($)MW
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts | MW	[1],[2]			4,686
November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Number of Facilities					12
Payments to Acquire Businesses, Gross		$ 207,000,000	$ 209,000,000
Business Acquisition, Consideration Transferred, Working Capital		$ 2,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets			30,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			669,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Assets			177,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets			876,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt			193,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Other Current and Non-Current Liabilities			32,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			225,000,000
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			282,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net			$ 369,000,000
Wind Farms [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts | MW	[1]			1,999
Wind Farms [Member] | November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts | MW					814
Financial Institutions [Member] | November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Taxable Income Allocation, Pre-Flip			99.00%
Taxable Income Allocation, Post-Flip			8.53%
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			$ 159,000,000
Pre-Flip Point [Member] | November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Percentage of Cash Available for Distributions			75.00%
Post-Flip Point [Member] | November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Percentage of Cash Available for Distributions			68.60%
Pre-determined Date Through Flip Point If Flip Has Not Occured [Member] | Financial Institutions [Member] | November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Percentage of Cash Available for Distributions			100.00%
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Business Acquisitions Busines52

Business Acquisitions Business Acquisitions - Desert Sunlight/Spring Canyon/Fuel Cell (Details)		Jun. 30, 2015	Jun. 29, 2015USD ($)	May 08, 2015	Apr. 30, 2015	Dec. 31, 2016MW	May 07, 2015
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1],[2]					4,686
Utility-Scale Solar [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]					610
Wind Farms [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]					1,999
Wind Farms [Member] | Spring Canyon [Member]
Business Acquisition [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired							90.10%
Wind Farms [Member] | Spring Canyon II [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts						32
Wind Farms [Member] | Spring Canyon III [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts						28
Thermal [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]					1,442
Desert Sunlight [Member]
Business Acquisition [Line Items]
Number of Facilities | $			2
Power Generation Capacity, Megawatts						550
Payments to Acquire Equity Method Investments | $			$ 285,000,000
Desert Sunlight [Member] | Utility-Scale Solar [Member]
Business Acquisition [Line Items]
Equity Method Investment, Ownership Percentage						25.00%
Supply Commitment [Member] | Spring Canyon [Member]
Business Acquisition [Line Items]
Weighted average remaining amortization period (in years)				24 years
Supply Commitment [Member] | UB Fuel Cell [Member]
Business Acquisition [Line Items]
Weighted average remaining amortization period (in years)					12 years
Supply Commitment [Member] | Southern California Edison [Member] | Desert Sunlight [Member]
Business Acquisition [Line Items]
Weighted average remaining amortization period (in years)		20 years
Supply Commitment [Member] | Pacific Gas and Electric [Member] | Desert Sunlight [Member]
Business Acquisition [Line Items]
Weighted average remaining amortization period (in years)		25 years
UB Fuel Cell [Member] | Thermal [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts						1.4
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Business Acquisitions Busines53

Business Acquisitions Business Acquisitions - January 2015 Drop Down Assets (Details) $ in Millions		Jan. 02, 2015USD ($)	Dec. 31, 2016MW	Feb. 19, 2016USD ($)	Nov. 02, 2015MW
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1],[2]		4,686
November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Acquisition, Consideration Transferred, Working Capital | $				$ 2
January 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Business Combination, Consideration Transferred | $		$ 489
Business Acquisition, Consideration Transferred, Working Capital | $		9
Business Combination, Consideration Transferred, Liabilities Incurred | $		737
Business Combination, Separately Recognized Transactions, Net Gains and Losses | $		61
AOCI Including Portion Attributable to Noncontrolling Interest, before Tax | $		$ 23
Wind Farms [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		1,999
Wind Farms [Member] | November 2015 Drop Down Assets [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts					814
Wind Farms [Member] | Laredo Ridge [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		80
Wind Farms [Member] | Buffalo Bear [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		19
Wind Farms [Member] | Taloga [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		130
Wind Farms [Member] | Pinnacle [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		55
Conventional Generation [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		1,945
Conventional Generation [Member] | Walnut Creek [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts	[1]		485
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Business Acquisitions Busines54

Business Acquisitions Business Acquisitions - Alta Wind (Details) $ / shares in Units, $ in Millions		Aug. 12, 2014USD ($)MW	Aug. 05, 2014USD ($)	Jul. 29, 2014USD ($)shares	Jul. 22, 2013USD ($)shares	Dec. 31, 2014USD ($)	Dec. 31, 2016USD ($)MW	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Jul. 30, 2014$ / shares
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts | MW	[1],[2]						4,686
Proceeds from the issuance of common stock					$ 468		$ 0	$ 599	$ 630
Business Combination, Acquisition Related Costs							1	$ 3	$ 4
Alta Wind Portfolio [Member]
Business Acquisition [Line Items]
Number of Facilities		7
Payments to Acquire Businesses, Gross		$ 923
Business Combination, Consideration Transferred		870
Business Acquisition, Consideration Transferred, Working Capital		53
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt		1,591
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		22
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Cash						$ 0
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current and Non-Current Assets		49
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Other Assets						(2)
Business Acquisition, Purchase Price Allocation, Other Assets, Adjusted		47
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		1,304
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Property, Plant, and Equipment						6
Business Acquisition, Purchase Price Allocation, Property, Plant and Equipment, Adjusted		1,310
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Finite-Lived Intangibles		1,177
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Intangibles						(6)
Business Acquisition, Purchase Price Allocation, Intangible Assets, Other than Goodwill, Adjusted		1,171
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		2,552
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Total Assets						(2)
Business Acquisition, Purchase Price Allocation, Assets Acquired, Adjusted		2,550
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Noncurrent Liabilities Longterm Debt						0
Business Acquisition, Purchase Price Allocation, Noncurrent Liabilities, Long-term Debt, Adjusted		1,591
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current and Non-Current Liabilities		38
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Current and Noncurrent Liabilities						(2)
Business Acquisition, Purchase Price Allocation, Current and Non-current Liabilities, Adjusted		36
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		1,629
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Financial Liabilities						(2)
Business Acquisition, Purchase Price Allocation, Liabilities Assumed, Adjusted		1,627
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Net		923
Business Combination, Provisional Information, Initial Accounting Incomplete, Adjustment, Net Assets Acquired						$ 0
Business Acquisition, Purchase Price Allocation, Assets Acquired (Liabilities Assumed), Net Adjusted		$ 923
Business Combination, Acquisition Related Costs							$ 2
Alta Wind Holdings [Member]
Business Acquisition [Line Items]
Power Generation Capacity, Megawatts | MW		947
Public Shareholders [Member] | Common Class A [Member]
Business Acquisition [Line Items]
Sale of Stock, Number of Shares Issued in Transaction | shares				12,075,000	22,511,250
Share Price | $ / shares										$ 54
Proceeds from the issuance of common stock				$ 630
5.375% Senior Notes due in 2024 [Member]
Business Acquisition [Line Items]
Debt Instrument, Interest Rate, Stated Percentage							5.375%
5.375% Senior Notes due in 2024 [Member] | NRG Yield Operating LLC [Member]
Business Acquisition [Line Items]
Proceeds from Issuance of Senior Long-term Debt			$ 500
Debt Instrument, Interest Rate, Stated Percentage			5.375%
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Business Acquisitions Busines55

Business Acquisitions Business Acquisitions - June 2014 Drop Down Assets (Details) - June 2014 Drop Down Assets [Member] $ in Millions	Jun. 30, 2014USD ($)
Business Acquisition [Line Items]
Business Combination, Consideration Transferred	$ 357
Business Acquisitions, Consideration Transferred, Purchase Price	349
Business Acquisition, Consideration Transferred, Working Capital	8
Business Combination, Consideration Transferred, Liabilities Incurred	$ 612

Property, Plant and Equipment56

Property, Plant and Equipment (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Property, Plant and Equipment
Property, plant and equipment, gross	$ 6,411	$ 6,660
Under construction	25	9
Less accumulated depreciation	(951)	(782)
Property, Plant and Equipment, Net	5,460	5,878
Prepaid Long Term Service Agreement	20
Support Equipment and Facilities [Member]
Property, Plant and Equipment
Property, plant and equipment, gross	6,215	6,480
Land and improvements
Property, Plant and Equipment
Property, plant and equipment, gross	$ 171	$ 171
Minimum [Member] | Support Equipment and Facilities [Member]
Property, Plant and Equipment
Property, plant and equipment, useful life	2 years
Maximum [Member] | Support Equipment and Facilities [Member]
Property, Plant and Equipment
Property, plant and equipment, useful life	40 years

Investments Accounted for by 57

Investments Accounted for by the Equity Method and Variable Interest Entities Investments Accounted for by the Equity Method and Variable Interest Entities - 2017 Drop Downs (Details) $ in Millions		Feb. 24, 2017USD ($)MW	Dec. 31, 2016MW
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts	[1],[2]		4,686
Subsequent Event [Member] | NRG [Member] | Agua Caliente [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Ownership		51.00%
Subsequent Event [Member] | NRG [Member] | Utah Portfolio [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions		50.00%
Subsequent Event [Member] | Scenario, Plan [Member] | Agua Caliente [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage		16.00%
Percentage of NRG's Ownership		31.00%
Power Generation Capacity, Megawatts		46
Power Purchase Agreement Period		25 years
Remaining Power Purchase Agreement term		22 years
Subsequent Event [Member] | Scenario, Plan [Member] | Utah Portfolio [Member]
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts		265
Remaining Power Purchase Agreement term		20 years
Subsequent Event [Member] | Scenario, Plan [Member] | 2017 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Business Combination, Consideration Transferred | $		$ 130
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Investments Accounted for by 58

Investments Accounted for by the Equity Method and Variable Interest Entities Investments Accounted for by the Equity Method and Variable Interest Entities - Summary Table (Details) - USD ($) $ in Millions		Jun. 29, 2015	Dec. 31, 2016	Dec. 31, 2015
Schedule of Equity Method Investments [Line Items]
Equity Method Investments			$ 710	$ 697
Retained Earnings, Undistributed Earnings from Equity Method Investees			30
Desert Sunlight [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments			$ 282
Payments to Acquire Equity Method Investments		$ 285
Business Acquisition, Consideration Transferred, Working Capital		$ 171
GCE Holding LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	[1]		50.00%
Equity Method Investments	[1]		$ 106
Retained Earnings, Undistributed Earnings from Equity Method Investees				$ 39
Elkhorn Ridge Wind, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			66.70%
Percentage of Ownership	[2]		50.30%
Equity Method Investments	[2]		$ 85
San Juan Mesa Wind Project, LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			75.00%
Percentage of Ownership	[2]		56.30%
Equity Method Investments	[2]		$ 74
NRG DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Ownership	[3]		95.00%
Equity Method Investments	[3]		$ 75
NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Ownership	[3]		95.00%
Equity Method Investments	[3]		$ 24
NRG RPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Ownership			95.00%
Equity Method Investments	[3]		$ 71
Avenal [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			50.00%
Equity Method Investments			$ (7)
Utility-Scale Solar [Member] | Desert Sunlight [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			25.00%
[1]	GenConn is a variable interest entity.
[2]	San Juan Mesa and Elkhorn Ridge are part of the Wind TE Holdco tax equity structure, as described below. San Juan Mesa and Elkhorn Ridge are owned 75% and 66.7%, respectively, by Wind TE Holdco. The Company owns 75% of the Class B interests in Wind TE Holdco.
[3]	NRG DGPV Holdco 1 LLC, NRG DGPV Holdco 2 LLC, and NRG RPV Holdco 1 LLC are tax equity structures and VIEs. The related allocations are described below.

Investments Accounted for by 59

Investments Accounted for by the Equity Method and Variable Interest Entities Investments Accounted for by the Equity Method and Variable Interest Entities - Not consolidated entities (Details) $ in Millions		1 Months Ended	3 Months Ended								12 Months Ended
		Apr. 30, 2010	Dec. 31, 2016USD ($)MW	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)MW	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Jul. 15, 2016	Sep. 22, 2010USD ($)
Schedule of Equity Method Investments [Line Items]
Pro-Rate Share of Debt Held by Unconsolidated Affiliates			$ 453								$ 453
Power Generation Capacity, Megawatts | MW	[1],[2]		4,686								4,686
Long-term Debt			$ 5,770				$ 5,656				$ 5,770	$ 5,656
Total operating revenues			232	$ 272	$ 283	$ 234	224	$ 256	$ 259	$ 214	1,021	953	$ 828
Operating Income			(99)	117	128	72	70	101	99	50	218	320	306
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest			(126)	$ 47	$ 63	$ 1	12	$ 32	$ 42	$ (21)	(15)	65	108
Current assets			645				416				645	416
Liabilities, Current			459				489				459	489
Liabilities, Noncurrent			$ 5,554				5,462				$ 5,554	5,462
Avenal [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			50.00%								50.00%
Power Generation Capacity, Megawatts | MW			45								45
Power Purchase Agreement Period		20 years
Notes and Loans Payable															$ 35
Debt Instrument, Interest Rate, Stated Percentage															4.50%
GCE Holding LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage	[3]		50.00%								50.00%
Total operating revenues											$ 72	78	82
Operating Income											38	40	40
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest											26	28	$ 28
Current assets			$ 36				36				36	36
Non-current assets			389				416				389	416
Liabilities, Current			16				16				16	16
Liabilities, Noncurrent			$ 196				215				$ 196	215
Desert Sunlight [Member]
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts | MW			550								550
Long-term Debt			$ 1,100								$ 1,100
Total operating revenues											211	206
Operating Income											129	124
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest											80	73
Current assets			281				310				281	310
Non-current assets			1,401				1,435				1,401	1,435
Liabilities, Current			64				82				64	82
Liabilities, Noncurrent			$ 1,043				1,086				$ 1,043	1,086
NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt							21					21
Desert Sunlight [Member] | Desert Sunlight [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt							1,100					1,100
EurusEnergy [Member] | Avenal [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investment, Ownership Percentage			50.00%								50.00%
SyndicateofBanks [Member] | Avenal [Member]
Schedule of Equity Method Investments [Line Items]
Long-term Debt			$ 134				143				$ 134	143			$ 209
CVSR Financing Agreement [Member]
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage														4.68%
Long-term Debt			$ 771				793				$ 771	793
Fixed Rate Notes [Member] | GCE Holding LLC [Member]
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.73%								4.73%
Long-term Debt			$ 212				$ 220				$ 212	$ 220
Line of Credit Facility, Maximum Borrowing Capacity			$ 237								$ 237
Working Capital Facility [Member] | GCE Holding LLC [Member]
Schedule of Equity Method Investments [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			1.875%								1.875%
Line of Credit Facility, Maximum Borrowing Capacity			$ 35								$ 35
Working Capital Facility [Member] | GenConn Facility [Member]
Schedule of Equity Method Investments [Line Items]
Line of Credit Facility, Fair Value of Amount Outstanding			$ 14								$ 14
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.
[3]	GenConn is a variable interest entity.

Investments Accounted for by 60

Investments Accounted for by the Equity Method and Variable Interest Entities Investments Accounted for by the Equity Method and Variable Interest Entities - VIEs that are consolidated (Details)		Feb. 19, 2016USD ($)	Nov. 03, 2015USD ($)	Jun. 30, 2015USD ($)	Dec. 31, 2016USD ($)MW	Dec. 31, 2015USD ($)	Nov. 02, 2015USD ($)MW	May 07, 2015
Schedule of Equity Method Investments [Line Items]
Other Assets					$ 2,278,000,000	$ 2,395,000,000
Power Generation Capacity, Megawatts | MW	[1],[2]				4,686
Property, Plant and Equipment, Net					$ 5,460,000,000	5,878,000,000
Assets					8,383,000,000	8,689,000,000
Liabilities					$ 6,013,000,000	$ 5,951,000,000
November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired							75.00%
Number of Facilities							12
Payments to Acquire Businesses, Gross		$ 207,000,000	$ 209,000,000
Business Acquisition, Consideration Transferred, Working Capital		$ 2,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment			669,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities			225,000,000
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			$ 282,000,000
Wind Farms [Member]
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts | MW	[1]				1,999
Wind Farms [Member] | November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts | MW							814
Wind Farms [Member] | Spring Canyon [Member]
Schedule of Equity Method Investments [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired								90.10%
Wind Farms [Member] | Spring Canyon II [Member]
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts | MW					32
Wind Farms [Member] | Spring Canyon III [Member]
Schedule of Equity Method Investments [Line Items]
Power Generation Capacity, Megawatts | MW					28
Financial Institutions [Member] | November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Taxable Income Allocation, Pre-Flip			99.00%
Taxable Income Allocation, Post-Flip			8.53%
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			$ 159,000,000
Pre-Flip Point [Member] | November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions			75.00%
Post-Flip Point [Member] | November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions			68.60%
Pre-determined Date Through Flip Point If Flip Has Not Occured [Member] | Financial Institutions [Member] | November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions			100.00%
November 2015 Drop Down Assets [Member]
Schedule of Equity Method Investments [Line Items]
Other Assets					$ 193,000,000
Property, Plant and Equipment, Net					441,000,000
Intangible Assets, Net (Excluding Goodwill)					2,000,000
Assets					636,000,000
Liabilities					209,000,000
Noncontrolling Interest in Variable Interest Entity					139,000,000
Net Assets					288,000,000
Alta X and XI TE Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Other Assets					17,000,000
Property, Plant and Equipment, Net					461,000,000
Intangible Assets, Net (Excluding Goodwill)					274,000,000
Assets					752,000,000
Liabilities					9,000,000
Noncontrolling Interest in Variable Interest Entity					107,000,000
Net Assets					$ 636,000,000
Alta X and XI TE Holdco [Member] | Financial Institutions [Member]
Schedule of Equity Method Investments [Line Items]
Taxable Income Allocation, Pre-Flip					99.00%
Taxable Income Allocation, Post-Flip					5.00%
Proceeds from Noncontrolling Interests				$ 119,000,000
Alta X and XI TE Holdco [Member] | Post-Flip Point [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					97.12%
Alta X and XI TE Holdco [Member] | Pre-determined Date Through Flip Point If Flip Has Not Occured [Member] | Financial Institutions [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					100.00%
Alta X and XI TE Holdco [Member] | First Year [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					100.00%
Alta X and XI TE Holdco [Member] | Second Year through Flip Point [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					94.34%
Spring Canyon [Member]
Schedule of Equity Method Investments [Line Items]
Other Assets					$ 4,000,000
Property, Plant and Equipment, Net					100,000,000
Intangible Assets, Net (Excluding Goodwill)					0
Assets					104,000,000
Liabilities					6,000,000
Noncontrolling Interest in Variable Interest Entity					67,000,000
Net Assets					$ 31,000,000
Spring Canyon [Member] | Pre-Flip Point [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					65.19%
Spring Canyon [Member] | Pre-Flip Point [Member] | Financial Institutions [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					34.81%
Spring Canyon [Member] | Post-Flip Point [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					95.00%
Spring Canyon [Member] | Post-Flip Point [Member] | Financial Institutions [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of Cash Available for Distributions					5.00%
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Investments Accounted for by 61

Investments Accounted for by the Equity Method and Variable Interest Entities Investments Accounted for by the Equity Method and Variable Interest Entities - VIEs that are not consolidated (Details) $ in Millions		Feb. 29, 2016USD ($)generatingunitMW	May 08, 2015generatingunitMW	Dec. 31, 2016USD ($)generatingunitMW	Sep. 30, 2016USD ($)	Jun. 30, 2016USD ($)	Mar. 31, 2016USD ($)	Dec. 31, 2015USD ($)	Sep. 30, 2015USD ($)	Jun. 30, 2015USD ($)	Mar. 31, 2015USD ($)	Dec. 31, 2016USD ($)generatingunitMW	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Aug. 05, 2016USD ($)
Schedule of Equity Method Investments [Line Items]
Current assets				$ 645				$ 416				$ 645	$ 416
Revenues				232	$ 272	$ 283	$ 234	224	$ 256	$ 259	$ 214	1,021	953	$ 828
Equity Method Investments				$ 710				697				$ 710	697
Power Generation Capacity, Megawatts | MW	[1],[2]			4,686								4,686
Liabilities, Current				$ 459				489				$ 459	489
Liabilities, Noncurrent				5,554				5,462				5,554	5,462
Operating Income				(99)	117	128	72	70	101	99	50	218	320	306
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest				(126)	$ 47	$ 63	$ 1	12	$ 32	$ 42	$ (21)	(15)	65	108
NRG DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	[3]			75								75
GCE Holding LLC [Member]
Schedule of Equity Method Investments [Line Items]
Current assets				36				36				36	36
Revenues												72	78	82
Equity Method Investments	[4]			106								106
Non-current assets				389				416				389	416
Liabilities, Current				16				16				16	16
Liabilities, Noncurrent				196				$ 215				196	215
Operating Income												38	40	40
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest												26	$ 28	$ 28
NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	[3]			24								24
NRG DGPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	[3]			99								99
NRG RPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments	[3]			$ 71								$ 71
Tax Equity Financed Portfolio of Leases - Community Solar [Member] | NRG DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Number of Solar Leases in Portfolio | generatingunit			10
Power Generation Capacity, Megawatts | MW			8
Remaining Lease Term			19 years
Tax Equity Financed Portfolio of Leases - Commercial PV 1 [Member] | NRG DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Number of Solar Leases in Portfolio | generatingunit			12
Power Generation Capacity, Megawatts | MW			37
Remaining Lease Term			18 years
Tax Equity Financed Portfolio of Leases - Commercial PV 1 [Member] | NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Number of Solar Leases in Portfolio | generatingunit		18
Power Generation Capacity, Megawatts | MW		28
Remaining Lease Term		21 years
Tax Equity Financed Portfolio of Leases - Commercial PV 2 [Member] | NRG DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Number of Solar Leases in Portfolio | generatingunit			3
Power Generation Capacity, Megawatts | MW			1
Remaining Lease Term			20 years
Tax Equity Financed Portfolio of Leases - Commercial PV 2 [Member] | NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Number of Solar Leases in Portfolio | generatingunit		21
Power Generation Capacity, Megawatts | MW		18
Remaining Lease Term		20 years
Existing Portfolio of Leases [Member] | NRG RPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Number of Solar Leases in Portfolio | generatingunit				2,200								2,200
Power Generation Capacity, Megawatts | MW				15								15
Remaining Lease Term												19 years
Tax Equity Financed Portfolio of Leases [Member] | NRG RPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Capital Contributions From Partners in Equity Method Investment				$ 59								$ 59
Number of Solar Leases in Portfolio | generatingunit				5,400								5,400
Power Generation Capacity, Megawatts | MW				31								31
Maximum [Member] | Tax Equity Financed Portfolio of Leases [Member] | NRG DGPV Holdco 1 [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments				$ 100								$ 100
Maximum [Member] | Tax Equity Financed Portfolio of Leases [Member] | NRG DGPV Holdco 2 [Member]
Schedule of Equity Method Investments [Line Items]
Equity Method Investments				50								50
Maximum [Member] | Tax Equity Financed Portfolio of Leases [Member] | NRG RPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Capital Contributions From Partners in Equity Method Investment		$ 150		60								$ 60			$ 100
Remaining Lease Term												19 years
NRG [Member] | NRG DGPV Holdco [Member]
Schedule of Equity Method Investments [Line Items]
Due to Related Parties, Current				$ 14								$ 14
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.
[3]	NRG DGPV Holdco 1 LLC, NRG DGPV Holdco 2 LLC, and NRG RPV Holdco 1 LLC are tax equity structures and VIEs. The related allocations are described below.
[4]	GenConn is a variable interest entity.

Fair Value of Financial Instr62

Fair Value of Financial Instruments Fair Value of Financial Instruments - Balance Sheet Grouping (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financing Receivable, Net	$ 30	$ 47
Long-term Debt and Capital Lease Obligations, Including Current Maturities	5,769	5,538
Reported Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Financing Receivable, Net	30	47
Long-term Debt and Capital Lease Obligations, Including Current Maturities	5,770	5,656
Fair Value, Inputs, Level 2 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	1,455	978
Fair Value, Inputs, Level 3 [Member] | Estimate of Fair Value Measurement [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Long-term Debt and Capital Lease Obligations, Including Current Maturities	$ 4,314	$ 4,560

Fair Value of Financial Instr63

Fair Value of Financial Instruments Fair Value of Financial Instruments - Recurring Fair Value Measurements (Details) - USD ($)		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Fair Value, Measurement with Unobservable Inputs Reconciliation, Recurring Basis, Asset Transfers Into Level 3		$ 0
Derivative Assets		3,000,000
Derivative Liabilities		72,000,000	$ 100,000,000
Fair Value, Net Derivative Asset (Liability) Measured on Recurring Basis, Unobservable Inputs Reconciliation, Transfers into Level 3		0
Fair Value, Assets, Level 1 to Level 2 Transfers, Amount		0	0
Fair Value, Assets, Level 2 to Level 1 Transfers, Amount		0	0
Fair Value, Liabilities, Level 1 to Level 2 Transfers, Amount		0	0
Fair Value, Liabilities, Level 2 to Level 1 Transfers, Amount		0	0
Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets	[1]	1,000,000
Fair Value, Inputs, Level 2 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets	[1]	2,000,000	0
Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets (Liabilities), at Fair Value, Net		0	0
Derivative Liabilities	[1]	0
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
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 Liabilities	[1]	72,000,000	100,000,000
Commodity contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		2,000,000
Derivative Liabilities		1,000,000
Commodity contracts | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		1,000,000
Derivative Liabilities		0
Commodity contracts | 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 Assets		1,000,000	0
Derivative Liabilities		1,000,000	2,000,000
Interest Rate Contract [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		1,000,000
Derivative Liabilities		71,000,000
Interest Rate Contract [Member] | Fair Value, Measurements, Recurring [Member] | Fair Value, Inputs, Level 1 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Assets		0
Derivative Liabilities		0
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 Assets		1,000,000	0
Derivative Liabilities		$ 71,000,000	$ 98,000,000
[1]	There were no assets or liabilities classified as Level 1 as of December 31, 2015. There were no assets or liabilities classified Level 3 as of December 31, 2016 and 2015.

Fair Value of Financial Instr64

Fair Value of Financial Instruments Fair Value of Financial Instruments - Derivative FV Measurement and Credit Risk (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
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	$ 1
Concentration Risk, Credit Risk, Financial Instrument, Maximum Exposure	$ 2,600
Estimated Counterparty Credit Risk Exposure to Certain Counterparties, Period	5 years

Accounting for Derivative Ins65

Accounting for Derivative Instruments and Hedging Activities Accounting for Derivative Instruments and Hedging Activities - FV of Derivatives (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Derivative [Line Items]
Derivative Liabilities	$ 72	$ 100
Derivative Assets	3
Derivative, Collateral, Obligation to Return Cash	0	0
Derivative, Collateral, Right to Reclaim Cash	0	0
Fair Value of Gross Derivative Assets/(Liabilities), Net	(69)
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset	0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral	(69)
Natural Gas [Member] | MMbtu [Member]
Derivative [Line Items]
Derivative, Notional Amount	3	4
Interest [Member] | Dollars
Derivative [Line Items]
Derivative, Notional Amount	1,839	1,991
Derivatives Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	65	90
Derivative Assets	1
Derivatives Not Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	7	10
Derivative Assets	2
Commodity contracts
Derivative [Line Items]
Derivative Liabilities	1
Derivative Assets	2
Derivative Asset, Fair Value, Gross Liability	0
Derivative instruments — affiliate	2
Derivative Liability, Fair Value, Gross Asset	0
Derivative Liability	1
Fair Value of Gross Derivative Assets/(Liabilities), Net	1
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset	0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral	1
Interest rate contracts current | Derivatives Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	26	34
Derivative Assets	0
Interest rate contracts current | Derivatives Not Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	2	3
Derivative Assets	0
Interest rate contracts long-term | Derivatives Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	39	56
Derivative Assets	1
Interest rate contracts long-term | Derivatives Not Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	4	5
Derivative Assets	0
Commodity contracts current | Derivatives Not Designated as Cash Flow Hedges
Derivative [Line Items]
Derivative Liabilities	1	$ 2
Derivative Assets	2
Interest Rate Contract [Member]
Derivative [Line Items]
Derivative Liabilities	71
Derivative Assets	1
Derivative Asset, Fair Value, Gross Liability	1
Derivative instruments — affiliate	0
Derivative Liability, Fair Value, Gross Asset	1
Derivative Liability	70
Fair Value of Gross Derivative Assets/(Liabilities), Net	(70)
Derivative Asset Fair Value Gross Liability Net Of Derivative Liability Fair Value Gross Asset	0
Derivative Asset, Fair Value, Amount Offset Against Collateral Net Of Derivative Liability, Fair Value, Amount Offset Against Collateral	$ (70)

Accounting for Derivative Ins66

Accounting for Derivative Instruments and Hedging Activities Accounting for Derivative Instruments and Hedging Activities - AOCI (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	$ (70)	$ (83)	$ (76)	$ (16)
Derivative Instruments, Gain (Loss) Reclassified from Accumulated OCI into Income, Effective Portion, Net	13	14	14
Other Comprehensive Income (Loss), Derivatives Qualifying as Hedges, Net of Tax	0	(21)	(74)
Accumulated other comprehensive loss	(28)	(27)	(9)
Loss expected to be realized from OCI during the next 12 months, net of tax	16
Accumulated Other Comprehensive Income (Loss), Cumulative Change in Gain (Loss) from Cash Flow Hedges, Tax Amount	16	16	6
Cash Flow Hedge Gain (Loss) to be Reclassified within Twelve Months, Tax	4
Noncontrolling Interest [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Accumulated Other Comprehensive Loss	$ (42)	$ (56)	$ (67)

Accounting for Derivative Ins67

Accounting for Derivative Instruments and Hedging Activities Accounting for Derivative Instruments and Hedging Activities - Impact of Statement of Operations (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss) on derivatives	$ 13	$ (7)	$ (60)
Interest Rate Contract [Member] | Interest Expense [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss) on derivatives	$ 2	16	(22)
Commodity contracts | Sales [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized gain/(loss) on derivatives		$ (2)	$ 2

Intangible Assets (Details)

Intangible Assets (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Finite-Lived Intangible Assets
Gross amount at the end of the period	$ 1,449	$ 1,455	$ 1,462
Gross amount at the beginning of the period	1,455	1,462
Less accumulated amortization	(163)	(93)
Net carrying amount	1,286	1,362
Amortization of Intangible Assets	$ 70	55	30
Finite-Lived Intangible Asset, Useful Life	20 years
Finite-Lived Intangible Assets, Other Changes	$ (6)	(7)
Contra Revenue Intangibles Amortization	69	54	29
Accumulated Amortization of Out of Market Contracts	3
Estimated amortization related to the Company's finite-lived intangible assets
Estimated intangible assets amortization, 2016	71
Estimated intangible assets amortization, 2017	71
Estimated intangible assets amortization, 2018	71
Estimated intangible assets amortization, 2019	71
Estimated intangible assets amortization, 2020	71
Customer Contracts
Finite-Lived Intangible Assets
Gross amount at the end of the period	15	15	15
Gross amount at the beginning of the period	15	15
Less accumulated amortization	(7)	(6)
Net carrying amount	8	9
Finite-Lived Intangible Assets, Other Changes	0	0
Customer Relationships
Finite-Lived Intangible Assets
Gross amount at the end of the period	66	66	66
Gross amount at the beginning of the period	66	66
Less accumulated amortization	(4)	(3)
Net carrying amount	62	63
Finite-Lived Intangible Assets, Other Changes	0	0
Supply Commitment Arrangement [Domain]
Finite-Lived Intangible Assets
Gross amount at the end of the period	1,264	1,264	1,270
Gross amount at the beginning of the period	1,264	1,270
Less accumulated amortization	(138)	(75)
Net carrying amount	1,126	1,189
Finite-Lived Intangible Assets, Other Changes	0	(6)
Other Intangible Assets [Member]
Finite-Lived Intangible Assets
Gross amount at the end of the period	6	6	6
Gross amount at the beginning of the period	6	6
Less accumulated amortization	(2)	(2)
Net carrying amount	4	4
Finite-Lived Intangible Assets, Other Changes	0	0
Emission Allowances [Member]
Finite-Lived Intangible Assets
Gross amount at the end of the period	9	15	16
Gross amount at the beginning of the period	15	16
Less accumulated amortization	(2)	(1)
Net carrying amount	7	14
Finite-Lived Intangible Assets, Other Changes	(6)	(1)
Research and Development Expense [Member]
Finite-Lived Intangible Assets
Gross amount at the end of the period	3	3	3
Gross amount at the beginning of the period	3	3
Less accumulated amortization	(1)	(1)
Net carrying amount	2	2
Finite-Lived Intangible Assets, Other Changes	0	0
Leasehold Rights [Member]
Finite-Lived Intangible Assets
Gross amount at the end of the period	86	86	$ 86
Gross amount at the beginning of the period	86	86
Less accumulated amortization	(9)	(5)
Net carrying amount	77	81
Finite-Lived Intangible Assets, Other Changes	0	$ 0
Out of Market Contracts [Member]
Finite-Lived Intangible Assets
Amortization	1
NRG Solar Blythe LLC [Member]
Finite-Lived Intangible Assets
Out of Market Contracts	4
Spring Canyon [Member]
Finite-Lived Intangible Assets
Out of Market Contracts	$ 3
Finite-Lived Intangible Asset, Useful Life	25 years
Alta Wind XI [Member]
Finite-Lived Intangible Assets
Out of Market Contracts	$ 5

Asset Impairments Asset Impai69

Asset Impairments Asset Impairments(Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment losses	$ 183	$ 0	$ 0
Elbow Creek [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment losses	117
Goat Wind [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment losses	60
Forward [Member]
Impaired Long-Lived Assets Held and Used [Line Items]
Impairment losses	$ 6

Long-term Debt Long-term Debt -

Long-term Debt Long-term Debt - Summary Table (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2016	Dec. 31, 2015	Oct. 31, 2016	Jul. 15, 2016
Debt Instrument [Line Items]
Long-term Debt		$ 5,770	$ 5,656
Debt Issuance Costs, Net		62	63
Long-term Debt, Excluding Current Maturities		5,426	5,329
Pro-Rate Share of Debt Held by Unconsolidated Affiliates		453
Current portion of long-term debt		282	264
Other Debt [Member]
Debt Instrument [Line Items]
Long-term Debt		0	2
Project [Domain]
Debt Instrument [Line Items]
Long-term Debt		4,314	4,254
3.25% Convertible Notes due 2020 [Member]
Debt Instrument [Line Items]
Interest Expense at Effective Rate		14	8
Long-term Debt		$ 271	266
Debt Instrument, Interest Rate, Stated Percentage		3.25%
Debt Instrument, Unamortized Discount		$ 16.5	21.5
3.5% Convertible Notes due 2019 [Member]
Debt Instrument [Line Items]
Interest Expense at Effective Rate		19	18
Long-term Debt		$ 335	330
Debt Instrument, Interest Rate, Stated Percentage		3.50%
Debt Instrument, Unamortized Discount		$ 10	15
5.375% Senior Notes due in 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.375%
Senior Notes		$ 500	500
5.00% Senior Notes due in 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.00%
Senior Notes		$ 350	0
NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		1 month LIBOR
Debt Instrument, Basis Spread on Variable Rate	[1]	2.50%
Long-term Debt		$ 0	306
Alpine Financing Agreement, due 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Long-term Debt		$ 145	154
Alta Wind I, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 242	252
Debt Instrument, Interest Rate, Stated Percentage		7.015%
Alta Wind II, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 191	198
Debt Instrument, Interest Rate, Stated Percentage		5.696%
Alta Wind III, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 198	206
Debt Instrument, Interest Rate, Stated Percentage		6.067%
Alta Wind IV, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 128	133
Debt Instrument, Interest Rate, Stated Percentage		5.938%
Alta Wind V, lease financing arrangement, due 2035 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 206	213
Debt Instrument, Interest Rate, Stated Percentage		6.071%
Alta Realty Investments, due 2031 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 31	33
Debt Instrument, Interest Rate, Stated Percentage		7.00%
Alta Wind Asset Management, due 2031 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3 month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.375%
Long-term Debt		$ 18	19
Avra Valley Financing Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 57	60
NRG Solar Blythe LLC Credit Agreement Due 2028 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.625%
Long-term Debt		$ 19	21
Borrego Financing Agreement, due 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.50%
Long-term Debt		$ 69	72
Borrego Financing Agreement, due 2038 [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		5.65%
West Holdings Credit Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 443	485
NRG Energy Center Minneapolis LLC Senior Secured Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		96	108
NRG Energy Center Minneapolis Series D Notes [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 125	$ 0
Debt Instrument, Interest Rate, Stated Percentage		3.55%		3.55%
Kansas South Facility, due 2031 [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.00%
Long-term Debt		$ 30	$ 33
Laredo Ridge Wind, LLC, due in 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.875%
Long-term Debt		$ 100	104
Marsh Landing Term Loan Facility [Member]
Debt Instrument [Line Items]
Long-term Debt		370	418
PFMG Financing Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 27	29
Debt Instrument, Interest Rate, Stated Percentage		6.00%
Roadrunner Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.625%
Long-term Debt		$ 37	$ 40
Kansas South Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		6 month LIBOR
South Trent Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.625%
Long-term Debt		$ 57	$ 62
Avra Valley [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.75%
High Desert Facility [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 49	$ 52
Tapestry Wind LLC due in 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.625%
Long-term Debt		$ 172	181
Viento Funding II, Inc., due in 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.75%
Long-term Debt		$ 178	189
Walnut Creek Energy, LLC, due in 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		1 month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.625%
Long-term Debt		$ 310	351
WCEP Holdings, LLC, due in 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		3.00%
Long-term Debt		$ 46	$ 46
Marsh Landing Tranche B due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.875%
Marsh Landing Tranche A due December 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.75%
NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.95%
NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		7.25%
High Desert Facility, due 2033 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		3-Month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.50%
TA - High Desert, due 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		5.15%
CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 771	$ 793
Debt Instrument, Interest Rate, Stated Percentage					4.68%
CVSR Holdco due 2037 [Member]
Debt Instrument [Line Items]
Long-term Debt		$ 199	$ 0
Debt Instrument, Interest Rate, Stated Percentage		4.68%
Letter of Credit [Member] | NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		$ 60
Letter of Credit [Member] | Alpine Financing Agreement, due 2022 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		37
Letter of Credit [Member] | Alta Wind I, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		16
Letter of Credit [Member] | Alta Wind II, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		27
Letter of Credit [Member] | Alta Wind III, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		27
Letter of Credit [Member] | Alta Wind IV, lease financing arrangement, due 2034 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		19
Letter of Credit [Member] | Alta Wind V, lease financing arrangement, due 2035 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		30
Letter of Credit [Member] | Alta Realty Investments, due 2031 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		0
Letter of Credit [Member] | Alta Wind Asset Management, due 2031 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		0
Letter of Credit [Member] | Avra Valley Financing Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		3
Letter of Credit [Member] | NRG Solar Blythe LLC Credit Agreement Due 2028 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		6
Letter of Credit [Member] | Borrego Financing Agreement, due 2024 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		5
Letter of Credit [Member] | West Holdings Credit Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		82
Letter of Credit [Member] | NRG Energy Center Minneapolis LLC Senior Secured Notes [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		0
Letter of Credit [Member] | NRG Energy Center Minneapolis Series D Notes [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		0
Letter of Credit [Member] | Kansas South Facility, due 2031 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		4
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		22
Letter of Credit [Member] | PFMG Financing Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		0
Letter of Credit [Member] | Roadrunner Financing Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		5
Letter of Credit [Member] | South Trent Financing Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		10
Letter of Credit [Member] | High Desert Facility [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		8
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] | Viento Funding II, Inc., due in 2023 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		27
Letter of Credit [Member] | Walnut Creek Energy, LLC, due in 2023 [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		41
Letter of Credit [Member] | WCEP Holdings LLC [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount		0
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
Minimum [Member] | Alpine [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate
Minimum [Member] | Alpine Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.75%
Minimum [Member] | West Holdings Credit Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		1 month LIBOR
Debt Instrument, Basis Spread on Variable Rate
Minimum [Member] | West Holdings Credit Agreement due 2023 Tranche A [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		1.625%
Minimum [Member] | West Holdings Credit Agreement due 2023 Tranche B [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate		2.25%
Minimum [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		2.339%
Maximum [Member] | Alpine [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate
Maximum [Member] | Alpine Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate
Maximum [Member] | West Holdings Credit Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Basis Spread on Variable Rate
Maximum [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		3.775%
[1]	(d) Applicable rate is determined by the Borrower Leverage Ratio, as defined in the credit agreement.

Long-term Debt Long-term Debt71

Long-term Debt Long-term Debt - Corporate Debt (Details)	Aug. 18, 2016USD ($)	Jul. 15, 2016USD ($)	Jun. 30, 2015	May 15, 2015	Aug. 05, 2014USD ($)	Dec. 31, 2016USD ($)$ / shares	Dec. 31, 2015USD ($)	Dec. 31, 2014USD ($)	Jun. 29, 2015USD ($)$ / shares	Mar. 31, 2014USD ($)	Feb. 11, 2014USD ($)
Debt Instrument [Line Items]
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt						$ 23,000,000	$ 23,000,000	$ 23,000,000
Long-term Debt						5,770,000,000	5,656,000,000
3.25% Convertible Notes due 2020 [Member]
Debt Instrument [Line Items]
Convertible Debt									$ 287,500,000
Interest Expense, Debt						9,000,000	5,000,000
Amortization of Debt Discount (Premium)						4,000,000	2,000,000
Amortization of Financing Costs						1,000,000	1,000,000
Interest Expense at Effective Rate						$ 14,000,000	8,000,000
Debt Instrument, Interest Rate, Stated Percentage						3.25%
Debt Instrument, Convertible, Conversion Price | $ / shares									$ 27.50
Debt Instrument, Convertible, Conversion Ratio			36.3636
Debt Instrument, Face Amount									$ 1,000
Adjustments to Additional Paid in Capital, Equity Component of Convertible Debt						$ 23,000,000
Percent of face value						96.625%
Long-term Debt, Fair Value						$ 278,000,000
Long-term Debt						271,000,000	266,000,000
Conversion Value of Convertible Debt						$ 165,000,000
3.5% Convertible Notes due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Effective Percentage						5.00%
Convertible Debt										$ 345,000,000
Interest Expense, Debt						$ 12,000,000	12,000,000
Amortization of Debt Discount (Premium)						5,000,000	4,000,000
Amortization of Financing Costs						2,000,000	2,000,000
Interest Expense at Effective Rate						$ 19,000,000	18,000,000
Debt Instrument, Interest Rate, Stated Percentage						3.50%
Debt Instrument, Convertible, Conversion Ratio				42.9644
Percent of face value						99.625%
Long-term Debt, Fair Value						$ 344,000,000
Long-term Debt						335,000,000	330,000,000
Conversion Value of Convertible Debt						$ 228,000,000
5.00% Senior Notes due in 2026 [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Unsecured Debt	$ 350,000,000
Debt Instrument, Interest Rate, Stated Percentage						5.00%
Senior Notes						$ 350,000,000	0
Convertible Debt [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount											$ 1,000
5.375% Senior Notes due in 2024 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage						5.375%
Senior Notes						$ 500,000,000	500,000,000
NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Long-term Debt						0	306,000,000
Line of Credit Facility, Maximum Borrowing Capacity						495,000,000
Proceeds from Issuance of Debt						60,000,000
Line of Credit Facility, Fair Value of Amount Outstanding						0
Repayments of Debt						366,000,000
CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage		4.68%
Long-term Debt						771,000,000	793,000,000
Proceeds from Issuance of Debt		$ 200,000,000
Proceeds from Debt, Net of Issuance Costs		$ 97,500,000
Letter of Credit [Member] | NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount						60,000,000
Letter of Credit [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Letters of Credit Outstanding, Amount						$ 0
November 2015 Drop Down Assets [Member] | NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Debt							$ 254,000,000
NRG Yield Operating LLC [Member] | 5.375% Senior Notes due in 2024 [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Senior Long-term Debt					$ 500,000,000
Debt Instrument, Interest Rate, Stated Percentage					5.375%
Common Class C [Member]
Debt Instrument [Line Items]
Common Stock Closing Price | $ / shares						$ 15.80
Common Class A [Member]
Debt Instrument [Line Items]
Common Stock Closing Price | $ / shares						$ 15.36

Long-term Debt Long-term Debt72

Long-term Debt Long-term Debt - Thermal/CVSR (Details) - USD ($) $ in Millions	Oct. 31, 2016	Jul. 15, 2016	Dec. 31, 2016	Sep. 01, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Long-term Debt			$ 5,770		$ 5,656
NRG Energy Center Minneapolis Series D Notes [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Debt	$ 125
Debt Instrument, Interest Rate, Stated Percentage	3.55%		3.55%
Long-term Debt			$ 125		0
CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Proceeds from Issuance of Debt		$ 200
Debt Instrument, Interest Rate, Stated Percentage		4.68%
Long-term Debt			$ 771		793
CVSR Holdco due 2037 [Member]
Debt Instrument [Line Items]
Debt Instrument, Interest Rate, Stated Percentage			4.68%
Long-term Debt			$ 199		$ 0
CVSR [Member]
Debt Instrument [Line Items]
Business Acquisition, Percentage of Voting Interests Acquired				51.05%
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt				$ 496
CVSR [Member] | CVSR Financing Agreement [Member]
Debt Instrument [Line Items]
Long-term Debt				771
CVSR [Member] | CVSR Holdco due 2037 [Member]
Debt Instrument [Line Items]
Long-term Debt				$ 200

Long-term Debt Long-term Debt73

Long-term Debt Long-term Debt - Avenal/Lease financing arrangements (Details) - USD ($) $ in Millions		Mar. 18, 2015	Dec. 31, 2016	Dec. 31, 2015	Jun. 30, 2015
Debt Instrument [Line Items]
Long-term Debt			$ 5,770	$ 5,656
NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis			1 month LIBOR
Debt Instrument, Basis Spread on Variable Rate	[1]		2.50%
Long-term Debt			$ 0	$ 306
Letter of Credit [Member] | Alta Wind I - V Lease financing arrangement [Member]
Debt Instrument [Line Items]
Long-term Debt			119
Alta Wind I - V Lease financing arrangement [Member]
Debt Instrument [Line Items]
Long-term Debt			$ 965
Avenal [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 43
Proceeds from Debt, Net of Issuance Costs		$ 20
Equity Method Investment, Ownership Percentage			50.00%
September 22, 2010 to March 18, 2015 [Member] | Avenal [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		6 month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.25%
March 18, 2015 to March 17, 2022 [Member] | Avenal [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		6 month LIBOR
Debt Instrument, Basis Spread on Variable Rate		1.75%
March 18, 2022 to March 17, 2027 [Member] | Avenal [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		6 month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.00%
March 18, 2027 through Maturity [Member] | Avenal [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis		6 month LIBOR
Debt Instrument, Basis Spread on Variable Rate		2.25%
Alta Wind I - V Lease financing arrangement [Member] | Revolving Credit Facility [Member] | NRG Yield Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Letters of Credit, Issued Amount			$ 23
Utility-Scale Solar [Member] | Avenal [Member]
Debt Instrument [Line Items]
Equity Method Investment, Ownership Percentage			50.00%		49.95%
[1]	(d) Applicable rate is determined by the Borrower Leverage Ratio, as defined in the credit agreement.

Long-term Debt Long-term Debt74

Long-term Debt Long-term Debt - Swaps/Maturities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2016USD ($)
Debt Instrument [Line Items]
2,016	$ 282
2,017	292
2,018	651
2,019	641
2,020	439
Thereafter	3,492
Long-term Debt, Gross	5,797
Interest Rate Swap [Member]
Debt Instrument [Line Items]
Derivative, Notional Amount	$ 1,839
Interest Rate Swap [Member] | NRG Solar Alpine LLC [Member] | Maturity - December 31, 2029 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	85.00%
Derivative, Fixed Interest Rate	2.744%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 115
Interest Rate Swap [Member] | NRG Solar Alpine LLC [Member] | Maturity - June 30, 2025 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	85.00%
Derivative, Fixed Interest Rate	2.421%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 8
Interest Rate Swap [Member] | NRG Solar Avra Valley [Member] | Maturity - November 30, 2030 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	85.00%
Derivative, Fixed Interest Rate	2.333%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 49
Interest Rate Swap [Member] | NRG Solar Blythe LLC [Member] | Maturity - June 25, 2028 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	3.563%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 14
Interest Rate Swap [Member] | Borrego [Member] | Maturity - December 31, 2029 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	1.125%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 7
Interest Rate Swap [Member] | NRG West Holdings LLC [Member] | Maturity - June 30, 2023 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	2.417%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 330
Interest Rate Swap [Member] | Kansas South [Member] | Maturity - June 30, 2023 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	2.368%
Debt Instrument, Description of Variable Rate Basis	6-Month LIBOR
Derivative, Notional Amount	$ 23
Interest Rate Swap [Member] | Laredo Ridge [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	2.31%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 79
Interest Rate Swap [Member] | Marsh Landing [Member] | Maturity - June 30, 2023 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	3.244%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 342
Interest Rate Swap [Member] | NRG Solar Roadrunner LLC [Member] | Maturity - December 31, 2029 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	4.313%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 28
Interest Rate Swap [Member] | South Trent Wind LLC [Member] | Maturity - June14, 2020 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	3.265%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 43
Interest Rate Swap [Member] | South Trent Wind LLC [Member] | Maturity - June 14, 2028 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	4.95%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 21
Interest Rate Swap [Member] | Tapestry Wind [Member] | Maturity - December 21, 2021 [Member] [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Derivative, Fixed Interest Rate	2.21%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 155
Interest Rate Swap [Member] | Tapestry Wind [Member] | Maturity - December 21, 2029 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	50.00%
Derivative, Fixed Interest Rate	3.57%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 60
Alta Wind Asset Management, due 2031 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	3 month LIBOR
Alta Wind Asset Management, due 2031 [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	100.00%
Derivative, Fixed Interest Rate	2.47%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 18
Viento Funding II, Inc., due in 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Viento Funding II, Inc., due in 2023 [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	90.00%
Debt Instrument, Description of Variable Rate Basis	6-mo. LIBOR
Derivative, Notional Amount	$ 160
Viento Funding II, Inc., due in 2023 [Member] | Interest Rate Swap [Member] | Maturity - June 30, 2028 [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	90.00%
Derivative, Fixed Interest Rate	4.985%
Debt Instrument, Description of Variable Rate Basis	6-mo. LIBOR
Derivative, Notional Amount	$ 65
Walnut Creek [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	75.00%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 276
WCEP Holdings, LLC, due in 2023 [Member]
Debt Instrument [Line Items]
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
WCEP Holdings, LLC, due in 2023 [Member] | Interest Rate Swap [Member]
Debt Instrument [Line Items]
Percentage of Debt Hedged by Interest Rate Derivatives	90.00%
Derivative, Fixed Interest Rate	4.003%
Debt Instrument, Description of Variable Rate Basis	3-Month LIBOR
Derivative, Notional Amount	$ 46

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended								5 Months Ended		12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2013		Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Numerator:
Net income attributable to NRG Yield, Inc.		$ (13)	$ 33	$ 32	$ 5	$ 11	$ 17	$ 10	$ (5)			$ 57	$ 33	$ 16
Common Class A [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Earnings Per Share, Diluted		$ (0.14)	$ 0.30	$ 0.29	$ 0.05
Weighted Average Number of Shares Outstanding, Diluted		35	49	49	35
Numerator:
Net income attributable to NRG Yield, Inc.										$ 8	[1]	$ 20	$ 14
Denominator:
Weighted average number of common shares outstanding — basic and diluted						35	35	35	35			35	35	28
Basic and diluted loss per share:
Earnings per weighted average common share — basic and diluted	[1]											$ 0.58	$ 0.40	$ 0.30
Common Class C [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Earnings Per Share, Diluted		$ (0.14)	$ 0.32	$ 0.31	$ 0.05
Weighted Average Number of Shares Outstanding, Diluted		63	73	73	63
Numerator:
Net income attributable to NRG Yield, Inc.										$ 8	[1]	$ 37	$ 19
Denominator:
Weighted average number of common shares outstanding — basic and diluted						63	63	35	35			63	49	28
Basic and diluted loss per share:
Earnings per weighted average common share — basic and diluted	[1]									$ 0.30
3.5% Convertible Notes due 2019 [Member] | Common Class A [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount												15	15	12
3.25% Convertible Notes due 2020 [Member] | Common Class C [Member]
Earnings Per Share, Basic, by Common Class, Including Two Class Method [Line Items]
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount												10	5	0
[1]	Net income attributable to NRG Yield, Inc. and basic and diluted earnings per share might not recalculate due to presenting values in millions rather than whole dollars.

Stockholders' Equity Stockhol76

Stockholders' Equity Stockholders' Equity (Details)		Sep. 02, 2016USD ($)	Feb. 19, 2016USD ($)	Nov. 03, 2015USD ($)	Jun. 29, 2015USD ($)shares	Jan. 02, 2015USD ($)	Jul. 29, 2014USD ($)shares	Jul. 22, 2013USD ($)$ / sharesshares	Jul. 31, 2013USD ($)	Dec. 31, 2016USD ($)$ / sharesMWshares	Sep. 30, 2016$ / shares	Jun. 30, 2016$ / shares	Mar. 31, 2016$ / shares	Dec. 31, 2016USD ($)$ / sharesMWshares	Dec. 31, 2015USD ($)$ / sharesshares	Dec. 31, 2014USD ($)	Sep. 01, 2016USD ($)	Nov. 02, 2015USD ($)MW
Statement of Stockholders' Equity
Dividends Payable, Date Declared														Feb. 15, 2017
Distribution Made to Limited Liability Company (LLC) Member, Distributions Paid, Per Unit | $ / shares										$ 0.25
Common Stock, Par or Stated Value Per Share | $ / shares										$ 0.01				$ 0.01	$ 0.01
Proceeds from the issuance of common stock								$ 468,000,000						$ 0	$ 599,000,000	$ 630,000,000
Expense Related to Distribution or Servicing and Underwriting Fees								$ 27,000,000
Common Stock, Dividends, Per Share, Declared | $ / shares														$ 0.26
Preferred Stock, Shares Authorized | shares								10,000,000		10,000,000				10,000,000	10,000,000
Preferred Stock, Par or Stated Value Per Share | $ / shares								$ 0.01		$ 0.01				$ 0.01	$ 0.01
Preferred stock, $0.01 par value; 10,000,000 shares authorized; none issued										$ 0				$ 0	$ 0
Payments of Capital Distribution														$ 113,000,000	$ 59,000,000	335,000,000
Dividends Payable, Date to be Paid														Mar. 15, 2017
Dividends Payable, Date of Record														Mar. 1, 2017
Power Generation Capacity, Megawatts | MW	[1],[2]									4,686				4,686
Common Class A [Member]
Statement of Stockholders' Equity
Common Stock, Shares Authorized | shares								500,000,000
Common Stock, Par or Stated Value Per Share | $ / shares										$ 0.01				$ 0.01
Common Class D [Member]
Statement of Stockholders' Equity
Distribution Made to Limited Liability Company (LLC) Member, Distributions Paid, Per Unit | $ / shares											$ 0.24	$ 0.23
Common Stock, Voting Rights														1/100th
Common Class B [Member]
Statement of Stockholders' Equity
Distribution Made to Limited Liability Company (LLC) Member, Distributions Paid, Per Unit | $ / shares													$ 0.225
Common Stock, Shares Authorized | shares								500,000,000
Common Class C [Member]
Statement of Stockholders' Equity
Proceeds from the issuance of common stock					$ 599,000,000
Investment Banking, Advisory, Brokerage, and Underwriting Fees and Commissions					$ 21,000,000
Public Shareholders [Member] | Common Class A [Member]
Statement of Stockholders' Equity
Sale of Stock, Number of Shares Issued in Transaction | shares							12,075,000	22,511,250
Proceeds from the issuance of common stock							$ 630,000,000
NRG
Statement of Stockholders' Equity
Payments to Acquire Interest in Subsidiaries and Affiliates									$ 395,000,000
NRG | Common Class B [Member]
Statement of Stockholders' Equity
Sale of Stock, Number of Shares Issued in Transaction | shares								42,738,750
NRG Yield, Inc. [Member]
Statement of Stockholders' Equity
Preferred Stock, Shares Authorized | shares										10,000,000				10,000,000	10,000,000
Preferred Stock, Par or Stated Value Per Share | $ / shares										$ 0.01				$ 0.01	$ 0.01
Preferred stock, $0.01 par value; 10,000,000 shares authorized; none issued										$ 0				$ 0	$ 0
NRG Yield, Inc. [Member] | Common Class A [Member]
Statement of Stockholders' Equity
Common Stock, Shares Authorized | shares										500,000,000				500,000,000	500,000,000
Common Stock, Par or Stated Value Per Share | $ / shares										$ 0.01				$ 0.01	$ 0.01
NRG Yield, Inc. [Member] | Common Class D [Member]
Statement of Stockholders' Equity
Common Stock, Shares Authorized | shares										500,000,000				500,000,000	500,000,000
NRG Yield, Inc. [Member] | Common Class B [Member]
Statement of Stockholders' Equity
Common Stock, Shares Authorized | shares										500,000,000				500,000,000	500,000,000
NRG Yield, Inc. [Member] | Common Class C [Member]
Statement of Stockholders' Equity
Common Stock, Shares Authorized | shares										500,000,000				500,000,000	500,000,000
NRG Yield LLC | NRG
Statement of Stockholders' Equity
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest							46.70%							46.70%
NRG Yield LLC | NRG Yield, Inc. [Member]
Statement of Stockholders' Equity
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest							53.30%							53.30%
CVSR [Member]
Statement of Stockholders' Equity
Business Combination, Separately Recognized Transactions, Net Gains and Losses														$ 112,000,000
AOCI Including Portion Attributable to Noncontrolling Interest, before Tax										$ 6,000,000				$ 6,000,000
Business Acquisition, Percentage of Voting Interests Acquired																	51.05%
Payments to Acquire Businesses, Gross		$ 78,500,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt																	$ 496,000,000
2015 Drop Down Asssets [Member]
Statement of Stockholders' Equity
Business Combination, Separately Recognized Transactions, Net Gains and Losses															$ 109,000,000
AOCI Including Portion Attributable to Noncontrolling Interest, before Tax															$ 32,000,000
November 2015 Drop Down Assets [Member]
Statement of Stockholders' Equity
Business Acquisition, Percentage of Voting Interests Acquired																		75.00%
Number of Facilities																		12
Payments to Acquire Businesses, Gross			$ 207,000,000	$ 209,000,000
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Noncurrent Liabilities, Long-term Debt				193,000,000
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value				282,000,000
January 2015 Drop Down Assets [Member]
Statement of Stockholders' Equity
Business Combination, Separately Recognized Transactions, Net Gains and Losses						$ 61,000,000
AOCI Including Portion Attributable to Noncontrolling Interest, before Tax						$ 23,000,000
June 2014 Drop Down Assets [Member]
Statement of Stockholders' Equity
Business Combination, Separately Recognized Transactions, Net Gains and Losses																$ 113,000,000
Wind Farms [Member]
Statement of Stockholders' Equity
Power Generation Capacity, Megawatts | MW	[1]									1,999				1,999
Wind Farms [Member] | November 2015 Drop Down Assets [Member]
Statement of Stockholders' Equity
Power Generation Capacity, Megawatts | MW																		814
Financial Institutions [Member] | November 2015 Drop Down Assets [Member]
Statement of Stockholders' Equity
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value				$ 159,000,000
Over-Allotment Option [Member] | NRG Yield, Inc. [Member] | Common Class C [Member]
Statement of Stockholders' Equity
Sale of Stock, Number of Shares Issued in Transaction | shares					3,678,000
[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 December 31, 2016.
[2]	NRG Yield's total generation capacity is net of 6 MWs for noncontrolling interest for Spring Canyon II and III. NRG Yield's generation capacity including this noncontrolling interest was 4,692 MWs.

Segment Reporting (Details)

Segment Reporting (Details) - USD ($) $ in Millions	3 Months Ended										5 Months Ended	12 Months Ended
	Dec. 31, 2016		Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015		Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2013	Dec. 31, 2016		Dec. 31, 2015		Dec. 31, 2014
Segment Reporting
Total operating revenues	$ 232		$ 272	$ 283	$ 234	$ 224		$ 256	$ 259	$ 214		$ 1,021		$ 953		$ 828
Cost of operations												306		321		277
Depreciation and amortization												297		297		233
Impairment losses												183		0		0
General and administrative												16		12		8
Acquisition-related transaction and integration costs												1		3		4
Operating Income	(99)		117	128	72	70		101	99	50		218		320		306
Equity in earnings of unconsolidated affiliates												37		26		17
Other Nonoperating Income (Expense)												3		3		6
Gains (Losses) on Extinguishment of Debt												0		(9)		(1)
Interest Expense												(274)		(263)		(216)
Income Before Income Taxes												(16)		77		112
Income tax (benefit) expense												(1)		12		4
Net Income	(126)		$ 47	$ 63	$ 1	12		$ 32	$ 42	$ (21)		(15)		65		108
Equity investments in affiliates	710					697						710		697
Capital Expenditures	23	[1]				30	[2]					23	[1]	30	[2]
Total Assets	8,383					8,689						8,383		8,689
Conventional Generation
Segment Reporting
Total operating revenues												333		336		317
Cost of operations												66		59		55
Depreciation and amortization												80		81		82
Impairment losses												0
General and administrative												0		0		0
Acquisition-related transaction and integration costs												0		0		0
Operating Income												187		196		180
Equity in earnings of unconsolidated affiliates												13		14		14
Other Nonoperating Income (Expense)												1		1		0
Gains (Losses) on Extinguishment of Debt														(7)		0
Interest Expense												(48)		(48)		(53)
Income Before Income Taxes												153		156		141
Income tax (benefit) expense												0		0		0
Net Income												153		156
Equity investments in affiliates	106					110						106		110
Capital Expenditures	7	[1]				4	[2]					7	[1]	4	[2]
Total Assets	1,993					2,102						1,993		2,102
Renewables
Segment Reporting
Total operating revenues												518		443		316
Cost of operations												126		136		83
Depreciation and amortization												197		197		133
Impairment losses												183
General and administrative												0		0		0
Acquisition-related transaction and integration costs												0		0		0
Operating Income												12		110		100
Equity in earnings of unconsolidated affiliates												24		12		3
Other Nonoperating Income (Expense)												2		2		5
Gains (Losses) on Extinguishment of Debt														(2)		(1)
Interest Expense												(141)		(147)		(126)
Income Before Income Taxes												(103)		(25)		(19)
Income tax (benefit) expense												0		0		0
Net Income												(103)		(25)
Equity investments in affiliates	604					587						604		587
Capital Expenditures	2	[1]				6	[2]					2	[1]	6	[2]
Total Assets	5,535					5,970						5,535		5,970
Thermal [Member]
Segment Reporting
Total operating revenues												170		174		195
Cost of operations												114		126		139
Depreciation and amortization												20		19		18
Impairment losses												0
General and administrative												0		0		0
Acquisition-related transaction and integration costs												0		0		0
Operating Income												36		29		38
Equity in earnings of unconsolidated affiliates												0		0		0
Other Nonoperating Income (Expense)												0		0		0
Gains (Losses) on Extinguishment of Debt														0		0
Interest Expense												(7)		(7)		(7)
Income Before Income Taxes												29		22		31
Income tax (benefit) expense												0		0		0
Net Income												29		22
Equity investments in affiliates	0					0						0		0
Capital Expenditures	14	[1]				20	[2]					14	[1]	20	[2]
Total Assets	426					428						426		428
Corporate
Segment Reporting
Total operating revenues												0		0		0
Cost of operations												0		0		0
Depreciation and amortization												0		0		0
Impairment losses												0
General and administrative												16		12		8
Acquisition-related transaction and integration costs												1		3		4
Operating Income												(17)		(15)		(12)
Equity in earnings of unconsolidated affiliates												0		0		0
Other Nonoperating Income (Expense)												0		0		1
Gains (Losses) on Extinguishment of Debt														0		0
Interest Expense												(78)		(61)		(30)
Income Before Income Taxes												(95)		(76)		(41)
Income tax (benefit) expense												(1)		12		4
Net Income												(94)		(88)		$ (45)
Equity investments in affiliates	0					0						0		0
Capital Expenditures	0	[1]				0	[2]					0	[1]	0	[2]
Total Assets	$ 429					$ 189						$ 429		$ 189
Affiliated Entity [Member]
Segment Reporting
General and administrative											$ 6
Southern California Edison [Member] | Conventional Generation
Segment Reporting
Customer's Percentage of Total Revenue												21.00%		23.00%		24.00%
Southern California Edison [Member] | Renewables
Segment Reporting
Customer's Percentage of Total Revenue												21.00%		17.00%		7.00%
PG&E [Member] | Conventional Generation
Segment Reporting
Customer's Percentage of Total Revenue												12.00%		13.00%		15.00%
PG&E [Member] | Renewables
Segment Reporting
Customer's Percentage of Total Revenue												11.00%		12.00%		13.00%
[1]	Includes accruals.
[2]	Includes accruals.

Income Taxes (Provision) (Detai

Income Taxes (Provision) (Details) - USD ($) $ in Millions	Jul. 29, 2014	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2011
Current
U.S. Federal		$ 0	$ 0	$ 0
Current State and Local Tax Expense (Benefit)		0	0		$ 0
Total — current		0	0	0
Deferred
U.S. Federal		(1)	10	2
State		0	2	2
Total — deferred		(1)	12	4
Income tax (benefit) expense		$ (1)	$ 12	$ 4
Effective tax rate (as a percent)		6.30%	15.60%	3.60%
U.S. federal statutory rate (as a percent)		35.00%
Reconciliation of the U.S. federal statutory rate to the Company's effective rate from continuing operations
Income Before Income Taxes		$ (16)	$ 77	$ 112
Tax at 35%		(6)	27	39
State taxes, net of federal benefit		0	2	(1)
Investment tax credits		(1)	(1)	0
Impact of non-taxable partnership earnings		5	(15)	(31)
Production tax credits, including prior year true-up		4	(4)	6
Change in state effective tax rate		0	0	1
Effective Income Tax Rate Reconciliation, Tax Contingency, Other, Amount		$ (3)	3	$ 0
Income Taxes Receivable			$ 6
NRG | NRG Yield LLC
Reconciliation of the U.S. federal statutory rate to the Company's effective rate from continuing operations
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest	46.70%	46.70%
NRG Yield, Inc. [Member] | NRG Yield LLC
Reconciliation of the U.S. federal statutory rate to the Company's effective rate from continuing operations
Limited Liability Company (LLC) or Limited Partnership (LP), Members or Limited Partners, Ownership Interest	53.30%	53.30%

Income Taxes (Deferred) (Detail

Income Taxes (Deferred) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Deferred Tax Liabilities, Gross [Abstract]
Total deferred tax assets, net of valuation allowance	$ 3,000,000	$ 27,000,000
Deferred Tax Liabilities, Gross	3,000,000	27,000,000
Deferred Tax Assets, Gross [Abstract]
Production tax credits carryforwards	5,000,000	10,000,000
Investment tax credits	1,000,000	1,000,000
U.S. Federal net operating loss carryforwards	226,000,000	181,000,000
State net operating loss carryforwards	3,000,000	5,000,000
Total deferred tax assets	235,000,000	197,000,000
Deferred Tax Assets, Valuation Allowance	16,000,000	0
Deferred Tax Assets, Net of Valuation Allowance	219,000,000	197,000,000
Deferred Tax Assets, Net	216,000,000	170,000,000
Deferred Tax Assets, Net, Excluding Valuation Allowance	$ 232,000,000	170,000,000
Unrecognized Tax Benefits		$ 0

Related Party Transactions (Det

Related Party Transactions (Details) - USD ($) $ in Millions	3 Months Ended	5 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2013	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Jan. 05, 2017	Oct. 31, 2016
Related Party Transaction
General and administrative			$ 16	$ 12	$ 8
Accounts payable — affiliate			40	86
GenOn Energy Services LLC [Member]
Related Party Transaction
Due to Affiliate			1	6
Affiliated Entity [Member]
Related Party Transaction
General and administrative		$ 6
NRG Repowering Holdings LLC [Member]
Related Party Transaction
Due to Affiliate			7
Payments				18
Receipt of payments	$ 11
coal, gas purchases					10
Cost of Natural Gas Purchases			1	5
Walnut Creek [Member] | NRG [Member] | Operations and Maintenance services [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party			3	3	2
NRG Yield [Member] | NRG [Member]
Related Party Transaction
Management Services Fee, Increase				0.5
General and administrative			10	8
NRG Yield [Member] | NRG [Member] | Scenario, Plan [Member]
Related Party Transaction
Management Services Fee, Annual			7.5
El Segundo [Member] | NRG El Segundo Operations, Inc. [Member]
Related Party Transaction
Due to Affiliate			1
Related Party Transaction, Expenses from Transactions with Related Party			4	4
CVSR [Member] | NRG Energy Services LLC [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party			4	7
Thermal [Member] | NRG [Member]
Related Party Transaction
Due to Affiliate			20	29
Accounts payable — affiliate			11
Accounts payable — affiliate			9
Related Party Transaction, Expenses from Transactions with Related Party			29	29	27
NRG Energy Center Dover [Member] | NRG [Member]
Related Party Transaction
Revenue from Related Parties			5
NRG Yield, Inc. [Member] | NRG [Member]
Related Party Transaction
Due to Affiliate			3
GCE Holding LLC [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party			5	4	6
Marsh Landing [Member] | GenOn Energy Services LLC [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party			14	13	13
Related Party Costs, Capitalized Amount					2
Marsh Landing [Member] | NRG RENOM [Member]
Related Party Transaction
Due to Affiliate			5	1
Related Party Transaction, Expenses from Transactions with Related Party			13	7
November 2015 Drop Down Assets [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Other Revenues from Transactions with Related Party				16	12
November 2015 Drop Down Assets [Member] | NRG [Member] | Support services [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party			2	3	1
Elbow Creek [Member] | NRG [Member]
Related Party Transaction
Revenue from Related Parties			8
NRG Energy Center Minneapolis LLC [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Expenses from Transactions with Related Party			$ 7	$ 8	$ 2
NECP [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Amount to be Paid Upon Completion of Project							$ 79
Subsequent Event [Member] | NECP [Member] | NRG [Member]
Related Party Transaction
Related Party Transaction, Amount to be Paid Upon Completion of Project						$ 87

Commitments and Contingencies81

Commitments and Contingencies (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Long-term Purchase Commitment [Line Items]
Operating Leases, Rent Expense	$ 15	$ 10	$ 9
Operating Leases, Future Minimum Payments Due, Next Twelve Months	9
Operating Leases, Future Minimum Payments, Due in Two Years	9
Operating Leases, Future Minimum Payments, Due in Three Years	10
Operating Leases, Future Minimum Payments, Due in Four Years	9
Operating Leases, Future Minimum Payments, Due in Five Years	9
Operating Leases, Future Minimum Payments, Due Thereafter	152
Operating Leases, Future Minimum Payments Due	198
Utilities Operating Expense, Purchased Power under Long-term Contracts	32	40	55
Purchase Obligation, Due in Next Twelve Months	13
Unrecorded Unconditional Purchase Obligation, Due within Two Years	5
Unrecorded Unconditional Purchase Obligation, Due within Three Years	2
Unrecorded Unconditional Purchase Obligation, Due within Four Years	3
Unrecorded Unconditional Purchase Obligation, Due within Five Years	3
Unrecorded Unconditional Purchase Obligation, Due after Five Years	19
Purchase Obligation	45
NRG [Member]
Long-term Purchase Commitment [Line Items]
Utilities Operating Expense, Purchased Power under Long-term Contracts	$ 8	$ 13	$ 12

Unaudited Quarterly Financial82

Unaudited Quarterly Financial Data (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended								5 Months Ended		12 Months Ended
		Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2013	[1]	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net Income/(Loss) per Weighted Average Common Share - Basic (in dollars per share)		$ (0.14)	$ 0.34	$ 0.33	$ 0.05	$ 0.12	$ 0.18	$ 0.15	$ (0.07)
Net income attributable to NRG Yield, Inc.		$ (13)	$ 33	$ 32	$ 5	$ 11	$ 17	$ 10	$ (5)			$ 57	$ 33	$ 16
Net Income		(126)	47	63	1	12	32	42	(21)			(15)	65	108
Operating Income		(99)	117	128	72	70	101	99	50			218	320	306
Total operating revenues		$ 232	$ 272	$ 283	$ 234	$ 224	$ 256	$ 259	$ 214			$ 1,021	$ 953	$ 828
Common Class A [Member]
Weighted Average Number of Shares Outstanding, Diluted		35	49	49	35
Weighted average number of common shares outstanding — basic and diluted						35	35	35	35			35	35	28
Net income attributable to NRG Yield, Inc.										$ 8		$ 20	$ 14
Earnings Per Share, Diluted		$ (0.14)	$ 0.30	$ 0.29	$ 0.05
Common Class C [Member]
Weighted Average Number of Shares Outstanding, Diluted		63	73	73	63
Net Income/(Loss) per Weighted Average Common Share - Basic (in dollars per share)	[1]											$ 0.58	$ 0.40
Weighted average number of common shares outstanding — basic and diluted						63	63	35	35			63	49	28
Net income attributable to NRG Yield, Inc.										$ 8		$ 37	$ 19
Earnings Per Share, Diluted		$ (0.14)	$ 0.32	$ 0.31	$ 0.05
[1]	Net income attributable to NRG Yield, Inc. and basic and diluted earnings per share might not recalculate due to presenting values in millions rather than whole dollars.

Yield, Inc. (Parent) Footnote83

Yield, Inc. (Parent) Footnotes (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Payments of Capital Distribution	$ 113	$ 59	$ 335
NRG Yield, Inc. [Member] | NRG Yield LLC [Member]
Payments of Capital Distribution	$ 92	$ 69	$ 41