Percentage of Ownership

No definition available.

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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- Definition

The reference rate for the variable rate of the debt instrument, such as LIBOR or the US Treasury rate and the maturity of the reference rate used, such as three months or six months LIBOR.

+ References

No definition available.

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- Definition

Incremental percentage increase (decrease) in the stated rate on a debt instrument.

+ References

No definition available.

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value of the amount outstanding under the credit facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13476-108611

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Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

This element represents the current and noncurrent portions of a long-term real estate loan with an initial maturity beyond one year or beyond the normal operating cycle, if longer, to finance building costs. The funds are disbursed as needed or in accordance with a prearranged plan; generally, a portion of the funds is disbursed at inception and the remainder as construction progresses. The money is repaid on completion of the project (generally one to seven years), usually from the proceeds of a mortgage loan. The rate is normally higher than the prime rate, and there is usually an origination fee. The effective yield on these loans tends to be high, and the lender has a security interest in the real property.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20,22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a borrowing with the highest claim on the assets of the entity in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle, if longer).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3255-108585

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

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- Details

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- Details

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- Details

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- Details

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- Details

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Debt and Capital Leases - Narrative (Details) - USD ($)			3 Months Ended		6 Months Ended
Debt and Capital Leases - Narrative (Details) - USD ($)	May 26, 2017	Jan. 24, 2017	Jun. 30, 2017	Sep. 30, 2016	Jun. 30, 2017	Dec. 31, 2016	May 23, 2016
Debt Instrument [Line Items]
Description of variable rate basis					3 month LIBOR
Long-term debt			$ 17,125,000,000		$ 17,125,000,000	$ 16,703,000,000
Recourse Debt
Debt Instrument [Line Items]
Long-term debt			7,785,000,000		7,785,000,000	7,795,000,000
Non Recourse Debt
Debt Instrument [Line Items]
Long-term debt			9,340,000,000		9,340,000,000	8,908,000,000
Revolving Credit Facility
Debt Instrument [Line Items]
Repayment of debt					125,000,000
Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	$ 83,000,000
Revolving Credit Facility \| Carlsbad Financing Agreement
Debt Instrument [Line Items]
Long-term construction loan	194,000,000
Revolving Credit Facility \| Working Capital Facility
Debt Instrument [Line Items]
Credit facility maximum borrowing capacity	4,000,000
Term loan facility, due 2023 \| Recourse Debt
Debt Instrument [Line Items]
Long-term debt			$ 1,881,000,000		$ 1,881,000,000	1,891,000,000
Term loan facility, due 2023 \| Recourse Debt \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%			2.25%
Description of variable rate basis		LIBOR
Change in interest rate		5000.00%
Term loan facility, due 2023 \| Recourse Debt \| London Interbank Offered Rate (LIBOR) floor
Debt Instrument [Line Items]
Basis spread on variable rate		0.75%
Description of variable rate basis		LIBOR
Senior Notes Due In 2020 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate, stated percentage				8.25%
Senior notes, due 2021 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate, stated percentage			7.875%	7.875%	7.875%
Long-term debt			$ 207,000,000		$ 207,000,000	207,000,000
NRG Yield Revolving Credit Facility
Debt Instrument [Line Items]
Borrowing outstanding under revolver			0		0
NRG Yield Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit outstanding under revolver			$ 68,000,000		$ 68,000,000
Agua Caliente Borrower 1, due 2038 \| Non Recourse Debt
Debt Instrument [Line Items]
Interest rate, stated percentage			5.43%		5.43%
Proceeds from issuance of senior secured debt			$ 130,000,000
Percentage of ownership			51.00%		51.00%
Long-term debt			$ 89,000,000		$ 89,000,000	0
Senior notes, due 2026 \| Recourse Debt
Debt Instrument [Line Items]
Interest rate, stated percentage			7.25%		7.25%		7.25%
Long-term debt			$ 1,000,000,000		$ 1,000,000,000	1,000,000,000	$ 1,000,000,000
Senior notes, due 2027 \| Recourse Debt
Debt Instrument [Line Items]
Proceeds from issuance of debt				$ 1,250,000,000
Interest rate, stated percentage			6.625%	6.625%	6.625%
Long-term debt			$ 1,250,000,000		$ 1,250,000,000	1,250,000,000
Carlsbad Energy Project \| Non Recourse Debt
Debt Instrument [Line Items]
Proceeds from issuance of debt	$ 407,000,000
Interest rate, stated percentage	4.12%		4.12%		4.12%
Long-term debt			$ 345,000,000		$ 345,000,000	$ 0