Debt - Long-term Debt Issuances and Borrowings (Details)	9 Months Ended
Sep. 30, 2018 USD ($)
FPL [Member] \| First mortgage bonds [Member]
Debt Instrument [Line Items]
Principal Amount	$ 1,500,000,000
NextEra Energy Capital Holdings, Inc. [Member] \| Debentures 1 [Member]
Debt Instrument [Line Items]
Principal Amount	$ 2,341,000,000
Interest Rate Terms	Variable
Minimum [Member] \| FPL [Member] \| First mortgage bonds [Member]
Debt Instrument [Line Items]
Interest Rate (as a percent)	3.95%
Maximum [Member] \| FPL [Member] \| First mortgage bonds [Member]
Debt Instrument [Line Items]
Interest Rate (as a percent)	4.125%

Face (par) amount of debt instrument at time of issuance.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28551-108399

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=114775985&loc=d3e28878-108400

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

Description of the interest rate as being fixed or variable, and, if variable, identification of the index or rate on which the interest rate is based and the number of points or percentage added to that index or rate to set the rate, and other pertinent information, such as frequency of rate resets.

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- Definition

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+ References

No definition available.

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