Summarized Financial Information of NEECH - Condensed Consolidating Statements of Comprehensive Income (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016
Condensed Financial Statements, Captions [Line Items]
Comprehensive income (loss) attributable to NEE	$ 6,667	$ 5,561	[1]	$ 3,003	[1]
Reportable Legal Entities [Member] | NEE (Guarantor) [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive income (loss) attributable to NEE	6,667	5,561		3,003
Reportable Legal Entities [Member] | Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive income (loss) attributable to NEE	4,434	3,710		1,442
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Comprehensive income (loss) attributable to NEE	$ (4,434)	$ (3,710)		$ (1,442)

[1] Amounts have been retrospectively adjusted as discussed in Note 14.