Variable Interest Entities (Details) $ in Millions	12 Months Ended
	Dec. 31, 2017 USD ($) variable_interest_entity entities MW	Dec. 31, 2016 USD ($) variable_interest_entity entities	Dec. 31, 2015 USD ($)	Jul. 01, 2014	Dec. 31, 2007 USD ($)
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities)	37
Investment in equity method investees	$ 2,321	$ 1,767	$ 1,063
NEP OpCo [Member]
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities) | variable_interest_entity	1
Carrying amount of assets, consolidated variable interest entity	$ 8,400	7,200
Carrying amount of liabilities, consolidated variable interest entity	6,200	5,000
Other variable interest entities [Member]
Variable Interest Entity [Line Items]
Investments in special purpose entities	2,634	2,505
FPL[Member] | Bankruptcy remote special purpose subsidiary [Member]
Variable Interest Entity [Line Items]
Storm-recovery bonds aggregate principal amount issued					$ 652
Proceeds from issuance of storm-recovery bonds					$ 644
Carrying amount of assets, consolidated variable interest entity	148	216
Carrying amount of liabilities, consolidated variable interest entity	147	214
FPL[Member] | Other variable interest entities [Member]
Variable Interest Entity [Line Items]
Investments in special purpose entities	$ 2,195	2,049
NEER [Member]
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities) | entities	36
Investment in equity method investees	$ 2,129	1,488
NEER [Member] | Gas and/or oil variable interest entities [Member]
Variable Interest Entity [Line Items]
Carrying amount of assets, consolidated variable interest entity	89	95
Carrying amount of liabilities, consolidated variable interest entity	$ 29	42
Natural gas and or oil electric generating facility capacity (in megawatts) | MW	110
NEER [Member] | Photovoltaic Solar Facility [Member]
Variable Interest Entity [Line Items]
Solar generating facility capability | MW	374
NEER [Member] | Special Purpose Entity that has Insufficient Equity at Risk [Member]
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities) | variable_interest_entity	1
Carrying amount of assets, consolidated variable interest entity	$ 490	502
Carrying amount of liabilities, consolidated variable interest entity	$ 502	$ 511
NEER [Member] | Wind variable interest entities [Member]
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities) | entities	31	27
Carrying amount of assets, consolidated variable interest entity	$ 13,100	$ 10,900
Carrying amount of liabilities, consolidated variable interest entity	$ 6,900	6,900
Wind electric generating facility capability (in megawatts) | MW	8,197
NEER [Member] | Gas and or Oil Variable Interest Entities [Member]
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities) | entities	1
Indirect Subsidiary of NextEra Energy Resources [Member] | Photovoltaic Solar Facility [Member]
Variable Interest Entity [Line Items]
Total number of consolidated variable interest entities (in entities) | entities	2
Carrying amount of assets, consolidated variable interest entity	$ 548	571
Carrying amount of liabilities, consolidated variable interest entity	$ 594	487
Ownership percentage (in hundredths)	50.00%
Solar generating facility capability | MW	277
Subsidiaries of NEE [Member]
Variable Interest Entity [Line Items]
Equity method investments, additional commitments to invest	$ 75	$ 30
Equity method investments, additional variable interest entities committed to invest in | variable_interest_entity	3	2
NEP OpCo [Member]
Variable Interest Entity [Line Items]
Noncontrolling interest ownership percentage	65.10%			79.90%
Other Investments [Member]
Variable Interest Entity [Line Items]
Investment in equity method investees	$ 248	$ 234