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.

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Debt and Capital Leases - Schedule of Long-term Debt and Capital Leases (Details) - USD ($) $ in Millions		6 Months Ended
	Jan. 24, 2017	Jun. 30, 2017	May 26, 2017	Dec. 31, 2016	Sep. 30, 2016	May 23, 2016
Debt Instrument [Line Items]
Long-term debt		$ 17,125		$ 16,703
Capital leases		6		6
Subtotal long-term debt and capital leases (including current maturities)		17,131		16,709
Current portion of long-term debt and capital leases		(1,042)		(516)
Less debt issuance costs		(208)		(188)
Discounts		(39)		(48)
Long-term debt and capital leases		15,842		15,957
Recourse Debt
Debt Instrument [Line Items]
Long-term debt		7,785		7,795
Recourse Debt \| Senior notes, due 2018
Debt Instrument [Line Items]
Long-term debt		$ 398		398
Interest rate, stated percentage		7.625%
Recourse Debt \| Senior notes, due 2021
Debt Instrument [Line Items]
Long-term debt		$ 207		207
Interest rate, stated percentage		7.875%			7.875%
Recourse Debt \| Senior notes, due 2022
Debt Instrument [Line Items]
Long-term debt		$ 992		992
Interest rate, stated percentage		6.25%
Recourse Debt \| Senior notes, due 2023
Debt Instrument [Line Items]
Long-term debt		$ 869		869
Interest rate, stated percentage		6.625%
Recourse Debt \| Senior notes, due 2024
Debt Instrument [Line Items]
Long-term debt		$ 733		733
Interest rate, stated percentage		6.25%
Recourse Debt \| Senior notes, due 2026
Debt Instrument [Line Items]
Long-term debt		$ 1,000		1,000		$ 1,000
Interest rate, stated percentage		7.25%				7.25%
Recourse Debt \| Senior notes, due 2027
Debt Instrument [Line Items]
Long-term debt		$ 1,250		1,250
Interest rate, stated percentage		6.625%			6.625%
Recourse Debt \| Term loan facility, due 2023
Debt Instrument [Line Items]
Long-term debt		$ 1,881		1,891
Recourse Debt \| Term loan facility, due 2023 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%	2.25%
Recourse Debt \| Tax-exempt bonds
Debt Instrument [Line Items]
Long-term debt		$ 455		455
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%
Recourse Debt \| Revolving Credit Facility \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%
Non Recourse Debt
Debt Instrument [Line Items]
Long-term debt		$ 9,340		8,908
Non Recourse Debt \| NRG Yield Operating LLC Senior Notes, due 2024
Debt Instrument [Line Items]
Long-term debt		$ 500		500
Interest rate, stated percentage		5.375%
Non Recourse Debt \| NRG Yield Operating LLC Senior Notes, due 2026
Debt Instrument [Line Items]
Long-term debt		$ 350		350
Interest rate, stated percentage		5.00%
Non Recourse Debt \| NRG Yield, Inc. Convertible Senior Notes, due 2019
Debt Instrument [Line Items]
Long-term debt		$ 345		345
Interest rate, stated percentage		3.50%
Non Recourse Debt \| NRG Yield, Inc. Convertible Senior Notes, due 2020
Debt Instrument [Line Items]
Long-term debt		$ 288		288
Interest rate, stated percentage		3.25%
Non Recourse Debt \| El Segundo Energy Center, due 2023
Debt Instrument [Line Items]
Long-term debt		$ 414		443
Non Recourse Debt \| El Segundo Energy Center, due 2023 \| LIBOR \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate		1.625%
Non Recourse Debt \| El Segundo Energy Center, due 2023 \| LIBOR \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate		2.25%
Non Recourse Debt \| Marsh Landing, due 2017 and 2023
Debt Instrument [Line Items]
Long-term debt		$ 358		370
Non Recourse Debt \| Alta Wind I - V lease financing arrangements, due 2034 and 2035
Debt Instrument [Line Items]
Long-term debt		939		965
Non Recourse Debt \| Walnut Creek, term loans due 2023
Debt Instrument [Line Items]
Long-term debt		$ 299		310
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]
Long-term debt		$ 284		287
Non Recourse Debt \| Utah Portfolio, due 2022 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.625%
Non Recourse Debt \| Tapestry, due 2021
Debt Instrument [Line Items]
Long-term debt		$ 166		172
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]
Long-term debt		$ 757		771
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]
Long-term debt		$ 193		199
Interest rate, stated percentage		4.68%
Non Recourse Debt \| Alpine, due 2022
Debt Instrument [Line Items]
Long-term debt		$ 142		145
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 2017 and 2025
Debt Instrument [Line Items]
Long-term debt		$ 85		96
Non Recourse Debt \| Energy Center Minneapolis, due 2017 and 2025 \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage		5.95%
Non Recourse Debt \| Energy Center Minneapolis, due 2017 and 2025 \| Maximum
Debt Instrument [Line Items]
Interest rate, stated percentage		7.25%
Non Recourse Debt \| NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2025
Debt Instrument [Line Items]
Interest rate, stated percentage		5.95%
Non Recourse Debt \| Energy Center Minneapolis, due 2031
Debt Instrument [Line Items]
Long-term debt		$ 125		125
Interest rate, stated percentage		3.55%
Non Recourse Debt \| Viento, due 2023
Debt Instrument [Line Items]
Long-term debt		$ 169		178
Non Recourse Debt \| Viento, due 2023 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.75%
Non Recourse Debt \| NRG Yield - other
Debt Instrument [Line Items]
Long-term debt		$ 569		540
Non Recourse Debt \| Subtotal NRG Yield debt (non-recourse to NRG)
Debt Instrument [Line Items]
Long-term debt		5,983		6,084
Non Recourse Debt \| Ivanpah, due 2033 and 2038
Debt Instrument [Line Items]
Long-term debt		$ 1,108		1,113
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]
Long-term debt		$ 345		0
Interest rate, stated percentage		4.12%	4.12%
Non Recourse Debt \| Agua Caliente, due 2037
Debt Instrument [Line Items]
Long-term debt		$ 843		849
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]
Long-term debt		$ 89		0
Interest rate, stated percentage		5.43%
Non Recourse Debt \| Cedro Hill, due 2025
Debt Instrument [Line Items]
Long-term debt		$ 156		163
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]
Long-term debt		$ 194		231
Interest rate, stated percentage		4.39%
Non Recourse Debt \| NRG Other
Debt Instrument [Line Items]
Long-term debt		$ 622		468
Non Recourse Debt \| Subtotal other NRG non-recourse debt
Debt Instrument [Line Items]
Long-term debt		$ 3,357		$ 2,824
Non Recourse Debt \| Marsh Landing Term Loan Due 2017 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		1.75%
Non Recourse Debt \| Marsh Landing Term Loan Due 2023 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		1.875%
Non Recourse Debt \| Alta Wind I
Debt Instrument [Line Items]
Interest rate, stated percentage		7.015%
Non Recourse Debt \| Alta Wind II
Debt Instrument [Line Items]
Interest rate, stated percentage		5.696%
Non Recourse Debt \| Alta Wind III
Debt Instrument [Line Items]
Interest rate, stated percentage		6.067%
Non Recourse Debt \| Alta Wind IV
Debt Instrument [Line Items]
Interest rate, stated percentage		5.938%
Non Recourse Debt \| Alta Wind V
Debt Instrument [Line Items]
Interest rate, stated percentage		6.071%