Summarized Financial Information of NEECH - Income Statement (Details) - USD ($) $ in Millions	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Operating revenues	$ 3,699	$ 4,805	$ 3,817	$ 3,835	$ 4,069	$ 4,954	$ 4,358	$ 4,104	$ 16,155	$ 17,486	$ 17,021
Operating expenses - net									(11,547)	(12,854)	(12,637)
Interest expense									(1,093)	(1,211)	(1,261)
Equity in earnings of subsidiaries									0	0	0
Other income (deductions) - net									873	569	522
INCOME (LOSS) BEFORE INCOME TAXES									4,388	3,990	3,645
Income tax expense (benefit)									1,383	1,228	1,176
Net Income (loss)	1,017	789	544	654	510	882	720	650	3,005	2,762	2,469
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									93	10	4
Net income (loss) attributable to parent	$ 966	$ 753	$ 540	$ 653	$ 507	$ 879	$ 716	$ 650	2,912	2,752	2,465
NEE (Guarantor) [Member]
Operating revenues									0	0	0
Operating expenses - net									(20)	(17)	(19)
Interest expense									(1)	(4)	(6)
Equity in earnings of subsidiaries									2,956	2,754	2,494
Other income (deductions) - net									5	1	1
INCOME (LOSS) BEFORE INCOME TAXES									2,940	2,734	2,470
Income tax expense (benefit)									28	(18)	5
Net Income (loss)									2,912	2,752	2,465
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
Net income (loss) attributable to parent									2,912	2,752	2,465
NEECH [Member]
Operating revenues									5,283	5,849	5,614
Operating expenses - net									(3,663)	(4,142)	(4,039)
Interest expense									(636)	(764)	(819)
Equity in earnings of subsidiaries									0	0	0
Other income (deductions) - net									793	498	487
INCOME (LOSS) BEFORE INCOME TAXES									1,777	1,441	1,243
Income tax expense (benefit)									354	299	262
Net Income (loss)									1,423	1,142	981
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									93	10	4
Net income (loss) attributable to parent									1,330	1,132	977
Other [Member]
Operating revenues									10,872	11,637	11,407
Operating expenses - net									(7,864)	(8,695)	(8,579)
Interest expense									(456)	(443)	(436)
Equity in earnings of subsidiaries									(2,956)	(2,754)	(2,494)
Other income (deductions) - net									75	70	34
INCOME (LOSS) BEFORE INCOME TAXES									(329)	(185)	(68)
Income tax expense (benefit)									1,001	947	909
Net Income (loss)									(1,330)	(1,132)	(977)
LESS NET INCOME ATTRIBUTABLE TO NONCONTROLLING INTERESTS									0	0	0
Net income (loss) attributable to parent									$ (1,330)	$ (1,132)	$ (977)