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			12 Months Ended
	Jan. 24, 2017	Jun. 30, 2016	Dec. 31, 2017	Dec. 07, 2017	May 26, 2017	Feb. 17, 2017	Dec. 31, 2016	Aug. 18, 2016	Aug. 02, 2016	May 23, 2016
Debt Instrument
Long-term debt			$ 16,633				$ 16,704
Capital Lease Obligations			5				6
Subtotal			16,638				16,710
Less current maturities			(688)				(516)
Less debt issuance costs			(204)				(188)
Discounts			(30)				(49)
Total long-term debt and capital leases			15,716				15,957
Debt Instrument, Unamortized Discount [Abstract]
Total discounts			(30)				(49)
Term loan facility, due 2023
Debt Instrument, Unamortized Discount [Abstract]
Discounts related to current maturities			$ 1
Alta Wind I - V lease financing arrangements, due 2034 and 2035 \| Low
Debt Instrument
Interest rate, stated percentage			5.696%
Alta Wind I - V lease financing arrangements, due 2034 and 2035 \| Maximum
Debt Instrument
Interest rate, stated percentage			7.015%
Recourse Debt
Debt Instrument
Long-term debt			$ 7,182				7,795
Recourse Debt \| Senior notes, due 2018
Debt Instrument
Long-term debt			$ 0				$ 398
Interest rate, stated percentage			7.625%				7.625%
Recourse Debt \| Senior notes, due 2021
Debt Instrument
Long-term debt			$ 0				$ 207
Interest rate, stated percentage			7.875%				7.875%		7.875%
Recourse Debt \| Senior notes, due 2022
Debt Instrument
Long-term debt			$ 992				$ 992
Interest rate, stated percentage			6.25%				6.25%
Recourse Debt \| Senior notes, due 2023
Debt Instrument
Long-term debt			$ 0				$ 869
Interest rate, stated percentage			6.625%	6.625%			6.625%
Recourse Debt \| Senior notes, due 2024
Debt Instrument
Long-term debt			$ 733				$ 733
Interest rate, stated percentage			6.25%				6.25%
Recourse Debt \| Senior notes, due 2026
Debt Instrument
Long-term debt			$ 1,000				$ 1,000
Interest rate, stated percentage			7.25%							7.25%
Recourse Debt \| Senior notes, due 2027
Debt Instrument
Long-term debt			$ 1,250				1,250
Interest rate, stated percentage			6.625%						6.625%
Recourse Debt \| Senior notes, due 2028
Debt Instrument
Long-term debt			$ 870				0
Interest rate, stated percentage			5.75%	5.75%
Recourse Debt \| Term loan facility, due 2023
Debt Instrument
Long-term debt		$ 1,900	$ 1,872				1,891
Debt Instrument, Unamortized Discount [Abstract]
Unamortized discount on debt instruments			$ (7)				(9)
Recourse Debt \| Term loan facility, due 2023 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)	2.25%	2.75%	2.25%
Recourse Debt \| Tax-exempt bonds
Debt Instrument
Long-term debt			$ 465				455
Recourse Debt \| Tax-exempt bonds \| Low
Debt Instrument
Interest rate, stated percentage			4.125%
Recourse Debt \| Tax-exempt bonds \| Maximum
Debt Instrument
Interest rate, stated percentage			6.00%
Non Recourse Debt
Debt Instrument
Long-term debt			$ 9,451				8,909
Non Recourse Debt \| NRG Yield Operating LLC Senior Notes, due 2024
Debt Instrument
Long-term debt			$ 500				500
Interest rate, stated percentage			5.375%
Non Recourse Debt \| NRG Yield Operating LLC Senior Notes, due 2026
Debt Instrument
Long-term debt			$ 350				350
Interest rate, stated percentage			5.00%					5.00%
Non Recourse Debt \| NRG Yield, Inc. Convertible Senior Notes, due 2019
Debt Instrument
Long-term debt			$ 345				345
Interest rate, stated percentage			3.50%
Debt Instrument, Unamortized Discount [Abstract]
Unamortized discount on debt instruments			$ (5)				(10)
Non Recourse Debt \| NRG Yield, Inc. Convertible Senior Notes, due 2020
Debt Instrument
Long-term debt			$ 288				288
Interest rate, stated percentage			3.25%
Debt Instrument, Unamortized Discount [Abstract]
Unamortized discount on debt instruments			$ (13)				(17)
Non Recourse Debt \| NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 (b)
Debt Instrument
Long-term debt			$ 55				0
Non Recourse Debt \| NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 (b) \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			2.50%
Non Recourse Debt \| El Segundo Energy Center, due 2023
Debt Instrument
Long-term debt			$ 400				443
Non Recourse Debt \| El Segundo Energy Center, due 2023 \| LIBOR \| Low
Debt Instrument
Basis spread on variable rate (as a percent)			1.75%
Non Recourse Debt \| El Segundo Energy Center, due 2023 \| LIBOR \| Maximum
Debt Instrument
Basis spread on variable rate (as a percent)			2.375%
Non Recourse Debt \| Marsh Landing, due 2017 and 2023
Debt Instrument
Long-term debt			$ 318				370
Non Recourse Debt \| Marsh Landing Term Loan Due 2017 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			1.75%
Non Recourse Debt \| Marsh Landing Term Loan Due 2023 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			1.875%
Non Recourse Debt \| Alta Wind I - V lease financing arrangements, due 2034 and 2035
Debt Instrument
Long-term debt			$ 926				965
Non Recourse Debt \| Walnut Creek, term loans due 2023
Debt Instrument
Long-term debt			$ 267				310
Non Recourse Debt \| Walnut Creek, term loans due 2023 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			1.625%
Non Recourse Debt \| Utah Portfolio, due 2022
Debt Instrument
Long-term debt			$ 278				287
Non Recourse Debt \| Utah Portfolio, due 2022 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			2.625%
Non Recourse Debt \| Tapestry, due 2021
Debt Instrument
Long-term debt			$ 162				172
Non Recourse Debt \| Tapestry, due 2021 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			1.625%
Non Recourse Debt \| CVSR, due 2037
Debt Instrument
Long-term debt			$ 746				771
Non Recourse Debt \| CVSR, due 2037 \| Low
Debt Instrument
Interest rate, stated percentage			2.339%
Non Recourse Debt \| CVSR, due 2037 \| Maximum
Debt Instrument
Interest rate, stated percentage			3.775%
Non Recourse Debt \| CVSR HoldCo, due 2037
Debt Instrument
Long-term debt			$ 194				199
Interest rate, stated percentage			4.68%
Non Recourse Debt \| Alpine, due 2022
Debt Instrument
Long-term debt			$ 135				145
Non Recourse Debt \| Alpine, due 2022 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			1.75%
Non Recourse Debt \| Energy Center Minneapolis, due 2025
Debt Instrument
Long-term debt			$ 83				96
Non Recourse Debt \| Energy Center Minneapolis, due 2025 \| Low
Debt Instrument
Interest rate, stated percentage			5.95%
Non Recourse Debt \| Energy Center Minneapolis, due 2025 \| Maximum
Debt Instrument
Interest rate, stated percentage			7.25%
Non Recourse Debt \| NRG Energy Center Minneapolis LLC Senior Secured Notes, due 2025
Debt Instrument
Interest rate, stated percentage			5.95%
Non Recourse Debt \| Energy Center Minneapolis, due 2031
Debt Instrument
Long-term debt			$ 125				125
Interest rate, stated percentage			3.55%
Non Recourse Debt \| Viento, due 2023
Debt Instrument
Long-term debt			$ 163				178
Non Recourse Debt \| Viento, due 2023 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			3.00%
Non Recourse Debt \| NRG Yield - other
Debt Instrument
Long-term debt			$ 579				603
Non Recourse Debt \| NRG Yield, Inc.
Debt Instrument
Long-term debt			5,914				6,147
Non Recourse Debt \| Ivanpah, due 2033 and 2038
Debt Instrument
Long-term debt			$ 1,073				1,113
Non Recourse Debt \| Ivanpah, due 2033 and 2038 \| Low
Debt Instrument
Interest rate, stated percentage			2.285%
Non Recourse Debt \| Ivanpah, due 2033 and 2038 \| Maximum
Debt Instrument
Interest rate, stated percentage			4.256%
Non Recourse Debt \| Carlsbad Energy Project
Debt Instrument
Long-term debt			$ 427				0
Interest rate, stated percentage					4.12%
Non Recourse Debt \| Carlsbad Energy Project \| LIBOR \| Low
Debt Instrument
Basis spread on variable rate (as a percent)			1.625%
Non Recourse Debt \| Carlsbad Energy Project \| LIBOR \| Maximum
Debt Instrument
Basis spread on variable rate (as a percent)			4.12%
Non Recourse Debt \| Agua Caliente, due 2037
Debt Instrument
Long-term debt			$ 818				849
Non Recourse Debt \| Agua Caliente, due 2037 \| Low
Debt Instrument
Interest rate, stated percentage			2.395%
Non Recourse Debt \| Agua Caliente, due 2037 \| Maximum
Debt Instrument
Interest rate, stated percentage			3.633%
Non Recourse Debt \| Agua Caliente Borrower 1, due 2038
Debt Instrument
Long-term debt			$ 89				0
Interest rate, stated percentage			5.43%			5.43%
Non Recourse Debt \| Cedro Hill, due 2029
Debt Instrument
Long-term debt			$ 151				163
Non Recourse Debt \| Cedro Hill, due 2029 \| LIBOR
Debt Instrument
Basis spread on variable rate (as a percent)			1.75%
Non Recourse Debt \| Midwest Generation, due 2019
Debt Instrument
Long-term debt			$ 152				231
Interest rate, stated percentage			4.39%
Debt Instrument, Unamortized Discount [Abstract]
Unamortized discount on debt instruments			$ (5)				(13)
Non Recourse Debt \| NRG Other Renewables
Debt Instrument
Long-term debt			647				269
Non Recourse Debt \| NRG Other
Debt Instrument
Long-term debt			180				137
Non Recourse Debt \| NRG Energy
Debt Instrument
Long-term debt			$ 3,537				$ 2,762