Summarized Financial Information of NEECH (Cash Flow Statement) (Details) - USD ($) $ in Millions	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	$ 5,225	$ 5,329	[1]
Capital Expenditures Independent Power Investments And Nuclear Fuel Purchases	(9,257)	(8,587)
Proceeds from sale of the fiber-optic telecommunications business	0	1,482	[1]
Capital contribution to Subsidiary	0	0
Sale of independent power and other investments of NEER	327	159	[1]
Proceeds from sale or maturity of securities in special use funds	2,579	2,059	[1]
Purchases of securities in special use funds	(2,860)	(2,146)	[1]
Distributions from equity method investees	637	7	[1]
Other - net	13	175	[1]
Net cash used in investing activities	(8,561)	(6,851)	[1]
Proceeds from Issuance of Long-term Debt	4,028	5,196	[1]
Retirements of long-term debt	(2,593)	(3,892)	[1]
Proceeds from differential membership investors	103	340	[1]
Net change in commercial paper	773	1,806	[1]
Proceeds from other short-term debt	625	200	[1]
Repayments of other short-term debt	(450)	(2)	[1]
Payments from related parties under CSCS agreement – net	720	0	[1]
Proceeds from Issuance of Common Stock	714	36	[1]
Payments of Dividends	(1,570)	(1,382)	[1]
Cash Dividends Received from (Paid to) Parent Company	0	0
Other - net	(275)	(540)	[1]
Net cash provided by (used in) financing activities	2,075	1,762	[1]
Effects of currency translation on cash, cash equivalents and restricted cash	(1)	0	[1]
Net increase (decrease) in cash, cash equivalents and restricted cash	(1,262)	240	[1]
Cash, cash equivalents and restricted cash at beginning of period	1,983	1,529	[1]
Cash, cash equivalents and restricted cash at end of period	721	1,769	[1]
Reportable Legal Entities [Member] | NextEra Energy (Guarantor) [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	2,839	1,464
Capital Expenditures Independent Power Investments And Nuclear Fuel Purchases	(124)	0
Proceeds from sale of the fiber-optic telecommunications business	0	0
Capital contribution to Subsidiary	(1,798)	(46)
Sale of independent power and other investments of NEER	0	0
Proceeds from sale or maturity of securities in special use funds	0	0
Purchases of securities in special use funds	0	0
Distributions from equity method investees	0	0
Other - net	12	7
Net cash used in investing activities	(1,910)	(39)
Proceeds from Issuance of Long-term Debt	0	0
Retirements of long-term debt	0	0
Proceeds from differential membership investors	0	0
Net change in commercial paper	0	0
Proceeds from other short-term debt	0	0
Repayments of other short-term debt	0	0
Payments from related parties under CSCS agreement – net	0	0
Proceeds from Issuance of Common Stock	714	36
Payments of Dividends	(1,570)	(1,382)
Cash Dividends Received from (Paid to) Parent Company	0	0
Other - net	(73)	(79)
Net cash provided by (used in) financing activities	(929)	(1,425)
Effects of currency translation on cash, cash equivalents and restricted cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	0	0
Cash, cash equivalents and restricted cash at beginning of period	1	1
Cash, cash equivalents and restricted cash at end of period	1	1
Reportable Legal Entities [Member] | NEECH Non-Guarantor Subsidiaries [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	1,578	1,937
Capital Expenditures Independent Power Investments And Nuclear Fuel Purchases	(5,536)	(4,808)
Proceeds from sale of the fiber-optic telecommunications business	0	1,482
Capital contribution to Subsidiary	0	0
Sale of independent power and other investments of NEER	327	159
Proceeds from sale or maturity of securities in special use funds	955	819
Purchases of securities in special use funds	(1,074)	(827)
Distributions from equity method investees	637	0
Other - net	(203)	177
Net cash used in investing activities	(4,894)	(2,998)
Proceeds from Issuance of Long-term Debt	2,434	4,995
Retirements of long-term debt	(1,014)	(3,819)
Proceeds from differential membership investors	103	340
Net change in commercial paper	2,255	995
Proceeds from other short-term debt	625	0
Repayments of other short-term debt	(200)	0
Payments from related parties under CSCS agreement – net	720	0
Proceeds from Issuance of Common Stock	0	0
Payments of Dividends	0	0
Cash Dividends Received from (Paid to) Parent Company	(2,727)	(722)
Other - net	(172)	(457)
Net cash provided by (used in) financing activities	2,024	1,332
Effects of currency translation on cash, cash equivalents and restricted cash	(1)	0
Net increase (decrease) in cash, cash equivalents and restricted cash	(1,293)	271
Cash, cash equivalents and restricted cash at beginning of period	1,807	1,375
Cash, cash equivalents and restricted cash at end of period	514	1,646
Consolidation, Eliminations [Member]
Condensed Financial Statements, Captions [Line Items]
Net cash provided by operating activities	808	1,928
Capital Expenditures Independent Power Investments And Nuclear Fuel Purchases	(3,597)	(3,779)
Proceeds from sale of the fiber-optic telecommunications business	0	0
Capital contribution to Subsidiary	1,798	46
Sale of independent power and other investments of NEER	0	0
Proceeds from sale or maturity of securities in special use funds	1,624	1,240
Purchases of securities in special use funds	(1,786)	(1,319)
Distributions from equity method investees	0	7
Other - net	204	(9)
Net cash used in investing activities	(1,757)	(3,814)
Proceeds from Issuance of Long-term Debt	1,594	201
Retirements of long-term debt	(1,579)	(73)
Proceeds from differential membership investors	0	0
Net change in commercial paper	(1,482)	811
Proceeds from other short-term debt	0	200
Repayments of other short-term debt	(250)	(2)
Payments from related parties under CSCS agreement – net	0	0
Proceeds from Issuance of Common Stock	0	0
Payments of Dividends	0	0
Cash Dividends Received from (Paid to) Parent Company	2,727	722
Other - net	(30)	(4)
Net cash provided by (used in) financing activities	980	1,855
Effects of currency translation on cash, cash equivalents and restricted cash	0	0
Net increase (decrease) in cash, cash equivalents and restricted cash	31	(31)
Cash, cash equivalents and restricted cash at beginning of period	175	153
Cash, cash equivalents and restricted cash at end of period	$ 206	$ 122

[1] Prior period amounts have been retrospectively adjusted as discussed in Note 11 - Restricted Cash.