Summarized Financial Information of Capital Holdings (Balance Sheet) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Dec. 31, 2016	Sep. 30, 2016	Dec. 31, 2015
Condensed Financial Statements, Captions [Line Items]
NEECH a 100% owned subsidiary of NEE	100.00%
PROPERTY, PLANT AND EQUIPMENT
Electric plant in service and other property	$ 92,548	$ 87,013
Accumulated depreciation and amortization	(21,460)	(20,101)
Total property, plant and equipment - net	71,088	66,912
CURRENT ASSETS
Cash and cash equivalents	1,381	1,292	$ 681	$ 571
Receivables	2,750	2,439
Other	2,896	3,678
Total current assets	7,027	7,409
OTHER ASSETS
Investment in subsidiaries	0	0
Other	18,666	15,672
Total other assets	18,666	15,672
TOTAL ASSETS	96,781	89,993
CAPITALIZATION
Common shareholders' equity	26,398	24,341
Noncontrolling interests	923	990
Long-term debt	30,345	27,818
Total capitalization	57,666	53,149
CURRENT LIABILITIES
Debt due within one year	4,614	3,022
Accounts payable	2,256	3,447
Other	4,734	4,450
Total current liabilities	11,604	10,919
OTHER LIABILITIES AND DEFERRED CREDITS
Asset retirement obligations	2,882	2,736
Deferred income taxes	12,563	11,101
Other	12,066	12,088
Total other liabilities and deferred credits	27,511	25,925
COMMITMENTS AND CONTINGENCIES
TOTAL CAPITALIZATION AND LIABILITIES	96,781	89,993
Reportable Legal Entities [Member] | NextEra Energy (Guarantor) [Member]
PROPERTY, PLANT AND EQUIPMENT
Electric plant in service and other property	23	28
Accumulated depreciation and amortization	(16)	(18)
Total property, plant and equipment - net	7	10
CURRENT ASSETS
Cash and cash equivalents	1	1	0	0
Receivables	340	88
Other	4	2
Total current assets	345	91
OTHER ASSETS
Investment in subsidiaries	26,139	24,323
Other	821	867
Total other assets	26,960	25,190
TOTAL ASSETS	27,312	25,291
CAPITALIZATION
Common shareholders' equity	26,398	24,341
Noncontrolling interests	0	0
Long-term debt	0	0
Total capitalization	26,398	24,341
CURRENT LIABILITIES
Debt due within one year	0	0
Accounts payable	1	1
Other	286	231
Total current liabilities	287	232
OTHER LIABILITIES AND DEFERRED CREDITS
Asset retirement obligations	0	0
Deferred income taxes	37	82
Other	590	636
Total other liabilities and deferred credits	627	718
COMMITMENTS AND CONTINGENCIES
TOTAL CAPITALIZATION AND LIABILITIES	27,312	25,291
Reportable Legal Entities [Member] | NEECH Non-Guarantor Subsidiaries [Member]
PROPERTY, PLANT AND EQUIPMENT
Electric plant in service and other property	41,530	38,671
Accumulated depreciation and amortization	(8,714)	(7,778)
Total property, plant and equipment - net	32,816	30,893
CURRENT ASSETS
Cash and cash equivalents	1,370	1,258	634	546
Receivables	1,441	1,615
Other	1,257	1,877
Total current assets	4,068	4,750
OTHER ASSETS
Investment in subsidiaries	0	0
Other	10,152	8,992
Total other assets	10,152	8,992
TOTAL ASSETS	47,036	44,635
CAPITALIZATION
Common shareholders' equity	8,732	7,699
Noncontrolling interests	923	990
Long-term debt	20,290	18,112
Total capitalization	29,945	26,801
CURRENT LIABILITIES
Debt due within one year	2,821	2,237
Accounts payable	1,559	2,668
Other	1,885	2,624
Total current liabilities	6,265	7,529
OTHER LIABILITIES AND DEFERRED CREDITS
Asset retirement obligations	880	816
Deferred income taxes	3,439	3,002
Other	6,507	6,487
Total other liabilities and deferred credits	10,826	10,305
COMMITMENTS AND CONTINGENCIES
TOTAL CAPITALIZATION AND LIABILITIES	47,036	44,635
Consolidation, Eliminations [Member]
PROPERTY, PLANT AND EQUIPMENT
Electric plant in service and other property	50,995	48,314
Accumulated depreciation and amortization	(12,730)	(12,305)
Total property, plant and equipment - net	38,265	36,009
CURRENT ASSETS
Cash and cash equivalents	10	33	$ 47	$ 25
Receivables	969	736
Other	1,635	1,799
Total current assets	2,614	2,568
OTHER ASSETS
Investment in subsidiaries	(26,139)	(24,323)
Other	7,693	5,813
Total other assets	(18,446)	(18,510)
TOTAL ASSETS	22,433	20,067
CAPITALIZATION
Common shareholders' equity	(8,732)	(7,699)
Noncontrolling interests	0	0
Long-term debt	10,055	9,706
Total capitalization	1,323	2,007
CURRENT LIABILITIES
Debt due within one year	1,793	785
Accounts payable	696	778
Other	2,563	1,595
Total current liabilities	5,052	3,158
OTHER LIABILITIES AND DEFERRED CREDITS
Asset retirement obligations	2,002	1,920
Deferred income taxes	9,087	8,017
Other	4,969	4,965
Total other liabilities and deferred credits	16,058	14,902
COMMITMENTS AND CONTINGENCIES
TOTAL CAPITALIZATION AND LIABILITIES	$ 22,433	$ 20,067