NEP Deconsolidation (Details) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018	Jul. 31, 2018	Dec. 31, 2017
Investment [Line Items]
Investment in equity method investees	$ 6,493,000,000	$ 6,493,000,000		$ 2,321,000,000
Deconsolidation, revaluation of retained investment, gain (loss), amount, before tax		3,900,000,000
Deconsolidation, revaluation of retained investment, gain (loss), amount, after tax		3,000,000,000
Plant, property, and equipment, decrease from deconsolidation		7,800,000,000
Long-term debt, decrease from deconsolidation		4,800,000,000
Noncontrolling interest, decrease from deconsolidation		2,700,000,000
Fee income	18,000,000	66,000,000
Due from related parties, current	38,000,000	38,000,000
Due from related parties, noncurrent	21,000,000	21,000,000
Guarantor obligations, current carrying value	635,000,000	635,000,000
Debt instrument, fair value disclosure	32,000,000	32,000,000
NextEra Energy Partners [Member]
Investment [Line Items]
Investment in equity method investees	$ 4,400,000,000	$ 4,400,000,000
Equity method investment, ownership percentage	2.50%	2.50%
Equity method investment, difference between carrying amount and underlying equity	$ 3,300,000,000	$ 3,300,000,000
NextEra Energy Partners [Member]
Investment [Line Items]
Due to related parties	807,000,000	$ 807,000,000
NEP OpCo [Member]
Investment [Line Items]
Limited liability company or limited partnership, members or limited partners, ownership interest		64.40%
NextEra Energy Partners [Member]
Investment [Line Items]
Issuances of common units	$ 82,000,000
At-the-market equity issuance program			$ 150,000,000