Percentage of Ownership

No definition available.

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- Definition

Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

+ References

Reference 1: 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(13))
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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section S99
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-Publisher FASB
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-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16)(a)(1))
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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.

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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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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)
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-SubTopic 10
-Section 50
-Paragraph 12
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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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Period Type:	instant

- 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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
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-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
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-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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.16)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section S99
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Data Type:	xbrli:monetaryItemType
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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Namespace Prefix:	us-gaap_
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

+ Details

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

- Definition

Amount of cash inflow from contractual arrangement with the lender, including but not limited to, letter of credit, standby letter of credit and revolving credit arrangements.

+ 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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(f))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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Balance Type:	debit
Period Type:	duration

- Definition

The cash inflow from a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

+ References

+ Details

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Period Type:	duration

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Debt and Capital Leases - Narrative (Details) - USD ($)						1 Months Ended	6 Months Ended
Debt and Capital Leases - Narrative (Details) - USD ($)	Jun. 04, 2018	Apr. 30, 2018	Mar. 21, 2018	May 26, 2017	Feb. 17, 2017	Jun. 30, 2018	Jun. 30, 2018	Jun. 19, 2018	Dec. 31, 2017
Debt Instrument [Line Items]
Amount						$ 16,092,000,000	$ 16,092,000,000	$ 120,000,000	$ 16,633,000,000
Investment Tax Credit Bridge Loan \| Rosamond Solar Portfolio LLC Financing Agreement
Debt Instrument [Line Items]
Bridge Loan	$ 175,000,000
Borrowings under ITC bridge loan						5,000,000
Investment Tax Credit Bridge Loan \| Rosamond Solar Portfolio LLC Financing Agreement \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
Recourse Debt
Debt Instrument [Line Items]
Amount						7,729,000,000	7,729,000,000		7,182,000,000
Non Recourse Debt
Debt Instrument [Line Items]
Amount						8,363,000,000	8,363,000,000		9,451,000,000
Revolving Credit Facility \| Rosamond Solar Portfolio LLC Financing Agreement
Debt Instrument [Line Items]
Long-term construction loan	$ 118,000,000
Credit facility maximum borrowing capacity	$ 33,000,000
Borrowings under construction loan						83,000,000
Revolving Credit Facility \| Rosamond Solar Portfolio LLC Financing Agreement \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
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]
Amount						1,862,000,000	$ 1,862,000,000		1,872,000,000
Term loan facility, due 2023 \| Recourse Debt \| LIBOR
Debt Instrument [Line Items]
Change in interest rate			0.50%
Basis spread on variable rate			1.75%				1.75%
Term loan facility, due 2023 \| Recourse Debt \| LIBOR floor
Debt Instrument [Line Items]
Basis spread on variable rate			0.00%
NRG Yield Revolving Credit Facility
Debt Instrument [Line Items]
Borrowing outstanding under revolver						0	$ 0
NRG Yield Revolving Credit Facility \| Non Recourse Debt
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%					2.50%
NRG Yield Revolving Credit Facility \| Letter of Credit
Debt Instrument [Line Items]
Letters of credit outstanding under revolver						$ 67,000,000	$ 67,000,000
NRG Energy Center Minneapolis Series D Notes \| Shelf Facility
Debt Instrument [Line Items]
Amount								$ 40,000,000
Agua Caliente Borrower 1, due 2038 \| Non Recourse Debt
Debt Instrument [Line Items]
Percentage of ownership					51.00%
Proceeds from issuance of senior secured debt					$ 130,000,000
Interest rate, stated percentage					5.43%	5.43%	5.43%
Amount						$ 86,000,000	$ 86,000,000		89,000,000
Carlsbad Energy Project \| Non Recourse Debt
Debt Instrument [Line Items]
Interest rate, stated percentage				4.12%
Proceeds from issuance of debt				$ 407,000,000
Amount						513,000,000	513,000,000		$ 427,000,000
Carlsbad Energy Project \| Notes Payable
Debt Instrument [Line Items]
Amount						$ 513,000,000	$ 513,000,000