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		3 Months Ended
	Mar. 21, 2018	Mar. 31, 2018	Dec. 31, 2017	May 26, 2017	Feb. 17, 2017
Debt Instrument [Line Items]
Long-term debt		$ 16,584	$ 16,633
Capital leases		4	5
Subtotal long-term debt and capital leases (including current maturities)		16,588	16,638
Current portion of long-term debt and capital leases		(956)	(688)
Less debt issuance costs		(201)	(204)
Discounts		(25)	(30)
Long-term debt and capital leases		$ 15,406	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]
Long-term debt		$ 7,177	7,182
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 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
Interest rate, stated percentage		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%
Recourse Debt \| Senior notes, due 2028
Debt Instrument [Line Items]
Long-term debt		$ 870	870
Interest rate, stated percentage		5.75%
Recourse Debt \| Term loan facility, due 2023
Debt Instrument [Line Items]
Long-term debt		$ 1,867	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]
Long-term debt		$ 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]
Long-term debt		$ 9,407	9,451
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 \| NRG Yield, Inc. Convertible Senior Notes, due 2019
Debt Instrument [Line Items]
Long-term debt		$ 500	500
Interest rate, stated percentage		5.375%
Non Recourse Debt \| NRG Yield, Inc. Convertible Senior Notes, due 2020
Debt Instrument [Line Items]
Long-term debt		$ 350	350
Interest rate, stated percentage		5.00%
Non Recourse Debt \| NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019
Debt Instrument [Line Items]
Long-term debt		$ 75	55
Non Recourse Debt \| NRG Yield LLC and NRG Yield Operating LLC Revolving Credit Facility, due 2019 \| LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.50%
Non Recourse Debt \| El Segundo Energy Center, due 2023
Debt Instrument [Line Items]
Long-term debt		$ 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]
Long-term debt		$ 309	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]
Long-term debt		$ 926	926
Non Recourse Debt \| Walnut Creek, term loans due 2023
Debt Instrument [Line Items]
Long-term debt		$ 259	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]
Long-term debt		$ 278	278
Non Recourse Debt \| Tapestry, due 2021
Debt Instrument [Line Items]
Long-term debt		$ 158	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]
Long-term debt		$ 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]
Long-term debt		$ 188	194
Interest rate, stated percentage		4.68%
Non Recourse Debt \| Alpine, due 2022
Debt Instrument [Line Items]
Long-term debt		$ 135	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 2025
Debt Instrument [Line Items]
Long-term debt		$ 83	83
Interest rate, stated percentage		595.00%
Non Recourse Debt \| Energy Center Minneapolis, due 2025 \| Minimum
Debt Instrument [Line Items]
Interest rate, stated percentage		3.55%
Non Recourse Debt \| Energy Center Minneapolis, due 2025 \| Maximum
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		$ 163	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]
Long-term debt		$ 183	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]
Long-term debt		$ 573	579
Non Recourse Debt \| Subtotal NRG Yield debt (non-recourse to NRG)
Debt Instrument [Line Items]
Long-term debt		6,038	6,083
Non Recourse Debt \| Ivanpah, due 2033 and 2038
Debt Instrument [Line Items]
Long-term debt		$ 1,068	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]
Long-term debt		$ 475	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]
Long-term debt		$ 815	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]
Long-term debt		$ 86	89
Interest rate, stated percentage		5.43%			5.43%
Non Recourse Debt \| Cedro Hill, due 2025
Debt Instrument [Line Items]
Long-term debt		$ 149	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]
Long-term debt		$ 132	152
Interest rate, stated percentage		4.39%
Non Recourse Debt \| Other Renewables Debt
Debt Instrument [Line Items]
Long-term debt		$ 466	478
Non Recourse Debt \| NRG Other
Debt Instrument [Line Items]
Long-term debt		178	180
Non Recourse Debt \| Subtotal other NRG non-recourse debt
Debt Instrument [Line Items]
Long-term debt		$ 3,369	$ 3,368