XML 80 R68.htm IDEA: XBRL DOCUMENT
v3.10.0.1

Debt and Capital Leases - Schedule of Long-term Debt and Capital Leases (Details) - USD ($) $ in Millions |  | 6 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | ---
Mar. 21, 2018 | Jun. 30, 2018 | Jun. 19, 2018 | Dec. 31, 2017 | May 26, 2017 | Feb. 17, 2017
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 16,092 | $ 120 | $ 16,633 |  |
Capital leases |  | 3 |  | 5 |  |
Subtotal long-term debt and capital leases (including current maturities) |  | 16,095 |  | 16,638 |  |
Current portion of long-term debt and capital leases |  | (952) |  | (688) |  |
Less debt issuance costs |  | (199) |  | (204) |  |
Discounts |  | (123) |  | (30) |  |
Long-term debt and capital leases |  | $ 14,821 |  | 15,716 |  |
Alta Wind I - V lease financing arrangements, due 2034 and 2035 | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 5.696% |  |  |  |
Alta Wind I - V lease financing arrangements, due 2034 and 2035 | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 7.015% |  |  |  |
Recourse Debt |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 7,729 |  | 7,182 |  |
Recourse Debt | Senior Notes, due 2022 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 977 |  | 992 |  |
Interest rate, stated percentage |  | 6.25% |  |  |  |
Recourse Debt | Senior Notes, due 2024 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 733 |  | 733 |  |
Interest rate, stated percentage |  | 6.25% |  |  |  |
Recourse Debt | Senior Notes, due 2026 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 1,000 |  | 1,000 |  |
Interest rate, stated percentage |  | 7.25% |  |  |  |
Recourse Debt | Senior Notes, due 2027 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 1,250 |  | 1,250 |  |
Interest rate, stated percentage |  | 6.625% |  |  |  |
Recourse Debt | Senior Notes, due 2028 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 841 |  | 870 |  |
Interest rate, stated percentage |  | 5.75% |  |  |  |
Recourse Debt | Convertible Senior Notes, due 2048 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 575 |  | 0 |  |
Interest rate, stated percentage |  | 2.75% |  |  |  |
Recourse Debt | Revolving loan facility, due 2018 and 2021 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 26 |  | 0 |  |
Recourse Debt | Revolving loan facility, due 2018 and 2021 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.75% |  |  |  |
Recourse Debt | Term loan facility, due 2023 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 1,862 |  | 1,872 |  |
Recourse Debt | Term loan facility, due 2023 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate | 1.75% | 1.75% |  |  |  |
Recourse Debt | Tax-exempt bonds |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 465 |  | 465 |  |
Recourse Debt | Tax-exempt bonds | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 4.125% |  |  |  |
Recourse Debt | Tax-exempt bonds | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 6.00% |  |  |  |
Non Recourse Debt |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 8,363 |  | 9,451 |  |
Non Recourse Debt | NRG Yield, Inc. Convertible Senior Notes, due 2019 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 345 |  | 345 |  |
Interest rate, stated percentage |  | 3.50% |  |  |  |
Non Recourse Debt | NRG Yield, Inc. Convertible Senior Notes, due 2020 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 288 |  | 288 |  |
Interest rate, stated percentage |  | 3.25% |  |  |  |
Non Recourse Debt | NRG Yield, Inc. Convertible Senior Notes, due 2019 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 500 |  | 500 |  |
Interest rate, stated percentage |  | 5.375% |  |  |  |
Non Recourse Debt | NRG Yield, Inc. Convertible Senior Notes, due 2020 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 350 |  | 350 |  |
Interest rate, stated percentage |  | 5.00% |  |  |  |
Non Recourse Debt | NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2023 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 0 |  | 55 |  |
Non Recourse Debt | NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2023 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.75% |  |  |  |
Non Recourse Debt | El Segundo Energy Center, due 2023 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 369 |  | 400 |  |
Non Recourse Debt | El Segundo Energy Center, due 2023 | LIBOR | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.75% |  |  |  |
Non Recourse Debt | El Segundo Energy Center, due 2023 | LIBOR | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 2.375% |  |  |  |
Non Recourse Debt | Marsh Landing, due 2023 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 305 |  | 318 |  |
Non Recourse Debt | Marsh Landing, due 2023 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 2.125% |  |  |  |
Non Recourse Debt | Alta Wind I - V lease financing arrangements, due 2034 and 2035 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 901 |  | 926 |  |
Non Recourse Debt | Walnut Creek, term loans due 2023 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 254 |  | 267 |  |
Non Recourse Debt | Walnut Creek, term loans due 2023 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.625% |  |  |  |
Non Recourse Debt | Utah Portfolio, due 2022 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 273 |  | 278 |  |
Non Recourse Debt | Tapestry, due 2021 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 155 |  | 162 |  |
Non Recourse Debt | Tapestry, due 2021 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.625% |  |  |  |
Non Recourse Debt | CVSR, due 2037 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 731 |  | 746 |  |
Non Recourse Debt | CVSR, due 2037 | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 2.339% |  |  |  |
Non Recourse Debt | CVSR, due 2037 | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 3.775% |  |  |  |
Non Recourse Debt | CVSR HoldCo, due 2037 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 188 |  | 194 |  |
Interest rate, stated percentage |  | 4.68% |  |  |  |
Non Recourse Debt | Alpine, due 2022 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 133 |  | 135 |  |
Non Recourse Debt | Alpine, due 2022 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.75% |  |  |  |
Non Recourse Debt | Energy Center Minneapolis, due 2031, 2033, 2035 and 2037 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 328 |  | 208 |  |
Non Recourse Debt | Viento, due 2023 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 154 |  | 163 |  |
Non Recourse Debt | Viento, due 2023 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 3.00% |  |  |  |
Non Recourse Debt | Buckthorn Solar, due 2018 and 2025 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 132 |  | 169 |  |
Non Recourse Debt | Buckthorn Solar, due 2018 and 2025 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.75% |  |  |  |
Non Recourse Debt | NRG Yield - other |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 564 |  | 579 |  |
Non Recourse Debt | Subtotal NRG Yield debt (non-recourse to NRG) |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | 5,970 |  | 6,083 |  |
Non Recourse Debt | Ivanpah, due 2033 and 2038 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 0 |  | 1,073 |  |
Non Recourse Debt | Ivanpah, due 2033 and 2038 | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 2.285% |  |  |  |
Non Recourse Debt | Ivanpah, due 2033 and 2038 | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 4.256% |  |  |  |
Non Recourse Debt | Carlsbad Energy Project |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 513 |  | 427 |  |
Interest rate, stated percentage |  |  |  |  | 4.12% |
Non Recourse Debt | Carlsbad Energy Project | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 1.625% |  |  |  |
Non Recourse Debt | Carlsbad Energy Project | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 4.12% |  |  |  |
Non Recourse Debt | Agua Caliente, due 2037 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 812 |  | 818 |  |
Non Recourse Debt | Agua Caliente, due 2037 | Minimum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 2.395% |  |  |  |
Non Recourse Debt | Agua Caliente, due 2037 | Maximum |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Interest rate, stated percentage |  | 3.633% |  |  |  |
Non Recourse Debt | Agua Caliente Borrower 1, due 2038 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 86 |  | 89 |  |
Interest rate, stated percentage |  | 5.43% |  |  |  | 5.43%
Non Recourse Debt | Cedro Hill, due 2025 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 144 |  | 151 |  |
Non Recourse Debt | Cedro Hill, due 2025 | LIBOR |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Basis spread on variable rate |  | 1.75% |  |  |  |
Non Recourse Debt | Midwest Generation, due 2019 |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 108 |  | 152 |  |
Interest rate, stated percentage |  | 4.39% |  |  |  |
Non Recourse Debt | NRG Other Renewables |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 623 |  | 478 |  |
Non Recourse Debt | NRG Other |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | 107 |  | 180 |  |
Non Recourse Debt | Subtotal other NRG non-recourse debt |  |  |  |  |  |
Debt Instrument [Line Items] |  |  |  |  |  |
Amount |  | $ 2,393 |  | $ 3,368 |  |

X
- Definition Amount equal to the present value (the principal) at the beginning of the lease term of minimum lease payments during the lease term (excluding that portion of the payments representing executory costs such as insurance, maintenance, and taxes to be paid by the lessor, together with any profit thereon) net of payments or other amounts applied to the principal through the balance sheet date. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 840 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737 Reference 2: 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 Reference 3: 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 + Details
Name: | us-gaap_CapitalLeaseObligations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Sum of the carrying values as of the balance sheet date of all debt, including all short-term borrowings, long-term debt, and capital lease obligations. + 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 210.9-03.13,16) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 2: 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 + Details
Name: | us-gaap_DebtAndCapitalLeaseObligations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Percentage points added to the reference rate to compute the variable rate on the debt instrument. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentBasisSpreadOnVariableRate1
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- 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 + Details
Name: | us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix: | us-gaap_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | instant

X
- 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. + Details
Name: | us-gaap_DebtInstrumentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after accumulated amortization, of debt discount (premium). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28567-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 1A -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 55 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399 + Details
Name: | us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28555-108399 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_DeferredFinanceCostsNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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
Name: | us-gaap_LongTermDebt
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt and capital lease obligation due after one year or beyond the normal operating cycle, if longer. + 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)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebtAndCapitalLeaseObligations
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of long-term debt and capital leases due within one year or the normal operating cycle, if longer. + 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 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_LongTermDebtAndCapitalLeaseObligationsCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_AltaWindIVLeasefinancingarrangementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MinimumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RangeAxis=us-gaap_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=nrg_RecourseDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_SeniorNotesDueIn2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_SeniorNotes2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_SeniorNotesdue2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_SeniorNotesdue2027Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_SeniorNotesdue2028Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_ConvertibleSeniorNotesDue2048Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_RevolvingLoanFacilityDue2018And2021Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_VariableRateAxis=us-gaap_LondonInterbankOfferedRateLIBORMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_TermLoanFacilityDue2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_TaxexemptBondsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_LongtermDebtTypeAxis=nrg_NonRecourseDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_A3.5ConvertibleNotesdue2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_A3.25ConvertibleNotesdue2020Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_A5.375SeniorNotesduein2024Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_A5.00SeniorNotesduein2026Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_NRGYieldandNRGYieldOperatingLLCRevolvingCreditFacilityDue2023MemberMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_WestHoldingsCreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_MarshLandingTermLoanDue2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_WalnutCreekEnergyLLCduein2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_UtahPortfolioMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_TapestryWindLLCduein2021Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_CVSRdue2037Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_CVSRHoldcodue2037Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_AlpineFinancingAgreementDue2022Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_NRGEnergyCenterMinneapolisLLCSeniorNotesdue203120332035and2037Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_VientoFundingIIInc.duein2023Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_BuckthornSolarDue2018And2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_NRGYieldOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_NrgYieldIncMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_IvanpahCreditAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_CarlsbadEnergyHoldingsLLCSeniorSecuredNotesdue2038Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_AguaCalienteFinancingAgreementMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_AguaCalienteBorrower1due2038Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_CedroHillWindLLCduein2025Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_MidwestGenerationdue2019Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_OtherRenewablesDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_OtherDebtMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DebtInstrumentAxis=nrg_NrgEnergyMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |