Summary of Significant Accounting and Reporting Policies - Additional Information (Details)		3 Months Ended								12 Months Ended
	Oct. 01, 2018 USD ($)	Dec. 31, 2019 USD ($) electric_generation_facility	Sep. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Dec. 31, 2019 USD ($) pipeline electric_generation_facility		Dec. 31, 2018 USD ($)		Dec. 31, 2017 USD ($)
Accounting Policies [Line Items]
Restricted Cash, Current		$ 3,000,000				$ 8,000,000				$ 3,000,000		$ 8,000,000
Payments of Debt Issuance Costs										$ 42,000,000
Number of wind generation facilities | electric_generation_facility		20								20
Revenues		$ 206,000,000	$ 253,000,000	$ 219,000,000	$ 177,000,000	155,000,000	$ 178,000,000	$ 225,000,000	$ 212,000,000	$ 855,000,000	[1]	771,000,000	[1]	$ 807,000,000	[1]
CITC		703,000,000				703,000,000				703,000,000		703,000,000
Property, plant and equipment - net		6,970,000,000				6,770,000,000				6,970,000,000		6,770,000,000
Allowance for doubtful accounts		0				0				0		0
Other non-current assets		137,000,000				128,000,000				137,000,000		128,000,000
Spare parts inventories		20,000,000				$ 19,000,000				20,000,000		19,000,000
Impairment of long-lived assets held-for-use										0		0
Impairment of intangible assets, finite-lived										0		0
Goodwill reduction	$ 0
Intangible amortization - PPAs										72,000,000		0		0
Amortization of deferred financing costs										11,000,000		12,000,000		11,000,000
Accretion expense										6,000,000		4,000,000		4,000,000
Additional AROs established										0		0		3,000,000
Decrease related to sale of Canadian Holdings										13,000,000
Goodwill, Other Increase (Decrease)										(44,000,000)
Write off of Deferred Debt Issuance Cost										22,000,000
Restricted Cash, Noncurrent		11,000,000								11,000,000
Convertible Investment Tax Credits Included In Other Receivables		124,000,000								124,000,000
Convertible Investment Tax Credit, Accounts Payable And Accrued Expenses		100,000,000								100,000,000
Convertible Investment Tax Credit, Other Current Liabilities		12,000,000								12,000,000
Convertible Investment Tax Credit, Due To Related Parties, Current		12,000,000								$ 12,000,000
Minimum [Member]
Accounting Policies [Line Items]
Useful life of property, plant, and equipment										3 years
Maximum [Member]
Accounting Policies [Line Items]
Useful life of property, plant, and equipment										50 years
Foreign Countries [Member]
Accounting Policies [Line Items]
Revenues										$ 125,000,000		234,000,000		$ 275,000,000
Non Affiliated Party [Member]
Accounting Policies [Line Items]
Number Of Pipelines | pipeline										1
NextEra Energy Partner GP [Member]
Accounting Policies [Line Items]
Noncontrolling interest		10,000								$ 10,000
June 2019 Acquisition [Member]
Accounting Policies [Line Items]
Additional AROs established										$ 38,000,000
NEP Renewables, LLC [Member]
Accounting Policies [Line Items]
Additional AROs established												$ 24,000,000
PG&E [Member] | Revenue Benchmark [Member]
Accounting Policies [Line Items]
Percentage of consolidated revenue, by customer										16.00%
Mex Gas Supply S.L. [Member] | Revenue Benchmark [Member]
Accounting Policies [Line Items]
Percentage of consolidated revenue, by customer										15.00%
Customer Relationships [Member]
Accounting Policies [Line Items]
Intangible amortization - PPAs										$ 17,000,000
Amortization next twelve months		17,000,000								17,000,000
Amortization expense - 2020		17,000,000								17,000,000
Amortization expense - 2021		17,000,000								17,000,000
Amortization expense - 2022		17,000,000								17,000,000
Amortization expense - 2023		17,000,000								$ 17,000,000
Customer Relationships [Member] | NET Holdings Management, LLC [Member]
Accounting Policies [Line Items]
Estimated useful life, in years										40 years
Power Purchase Agreements [Member]
Accounting Policies [Line Items]
Amortization next twelve months		103,000,000								$ 103,000,000
Amortization expense - 2020		103,000,000								103,000,000
Amortization expense - 2021		103,000,000								103,000,000
Amortization expense - 2022		103,000,000								103,000,000
Amortization expense - 2023		$ 103,000,000								$ 103,000,000
Non Affiliated Party [Member]
Accounting Policies [Line Items]
Noncontrolling interest, percent ownership by noncontrolling owners		10.00%								10.00%
NEP OpCo [Member]
Accounting Policies [Line Items]
Noncontrolling interest, percent ownership by noncontrolling owners		60.80%								60.80%
Silver State South Solar, LLC [Member]
Accounting Policies [Line Items]
Noncontrolling interest, percent ownership by noncontrolling owners		50.00%								50.00%

[1] Includes related party revenues of approximately $8 million, $4 million and $9 million for 2019, 2018 and 2017, respectively.