Summarized Financial Information of Capital Holdings (Statement of Operations) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Condensed Consolidating Statements of Income
Operating revenues	$ 4,808	$ 4,805	$ 13,185	$ 12,457
Operating expenses - net	(3,409)	(3,526)	(8,095)	(8,775)
Interest expense	(381)	(369)	(1,171)	(1,480)
Equity in earnings of subsidiaries	0	0	0	0
Other income - net	202	297	662	665
INCOME BEFORE INCOME TAXES	1,220	1,207	4,581	2,867
Income tax expense (benefit)	364	418	1,329	879
Net Income (Loss)	856	789	3,252	1,988
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	9	36	29	42
Net income (loss) attributable to NEE	847	753	3,223	1,946
Comprehensive income (loss) attributable to NEE	892	799	3,341	2,078
Consolidation, Eliminations [Member]
Condensed Consolidating Statements of Income
Operating revenues	3,443	3,279	9,031	8,326
Operating expenses - net	(2,424)	(2,489)	(6,276)	(6,005)
Interest expense	(121)	(114)	(360)	(342)
Equity in earnings of subsidiaries	(830)	(765)	(3,179)	(1,989)
Other income - net	21	17	31	57
INCOME BEFORE INCOME TAXES	89	(72)	(753)	47
Income tax expense (benefit)	355	266	919	775
Net Income (Loss)	(266)	(338)	(1,672)	(728)
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0	0	0	0
Net income (loss) attributable to NEE	(266)	(338)	(1,672)	(728)
Comprehensive income (loss) attributable to NEE	(312)	(384)	(1,784)	(866)
Reportable Legal Entities [Member] | NextEra Energy (Guarantor) [Member]
Condensed Consolidating Statements of Income
Operating revenues	0	0	0	0
Operating expenses - net	(3)	(5)	(13)	(14)
Interest expense	(1)	0	(2)	(1)
Equity in earnings of subsidiaries	830	765	3,179	1,989
Other income - net	0	4	1	5
INCOME BEFORE INCOME TAXES	826	764	3,165	1,979
Income tax expense (benefit)	(21)	11	(58)	33
Net Income (Loss)	847	753	3,223	1,946
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	0	0	0	0
Net income (loss) attributable to NEE	847	753	3,223	1,946
Comprehensive income (loss) attributable to NEE	892	799	3,341	2,078
Reportable Legal Entities [Member] | NEECH Non-Guarantor Subsidiaries [Member]
Condensed Consolidating Statements of Income
Operating revenues	1,365	1,526	4,154	4,131
Operating expenses - net	(982)	(1,032)	(1,806)	(2,756)
Interest expense	(259)	(255)	(809)	(1,137)
Equity in earnings of subsidiaries	0	0	0	0
Other income - net	181	276	630	603
INCOME BEFORE INCOME TAXES	305	515	2,169	841
Income tax expense (benefit)	30	141	468	71
Net Income (Loss)	275	374	1,701	770
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS	9	36	29	42
Net income (loss) attributable to NEE	266	338	1,672	728
Comprehensive income (loss) attributable to NEE	$ 312	$ 384	$ 1,784	$ 866