Commitment to invest in clean power and technology businesses.

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Commitments included in planned capital expenditures

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Joint Obligations of NEECH and NEER included in the NEER amounts above due in the next year

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Sets forth the number of megawatts that must be purchased annually within the specified time period of the agreement to avoid penalties or unfavorable effects on pricing, among other adverse consequences.

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No definition available.

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Public Utilities, Termination of Operations, Payment

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Required Capacity And Or Minimum Payments Abstract

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Estimated required capacity and/or minimum payments after the fifth year.

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Estimated required capacity and/or minimum payments for the fifth year.

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Estimated required capacity and/or minimum payments for the fourth year.

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Estimated required capacity and/or minimum payments for the remainder of the current year.

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No definition available.

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Estimated required capacity and/or minimum payments for the second year.

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Estimated required capacity and/or minimum payments for the third year.

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For capacity payments, total capacity payments under contracts, substantially all of which are recoverable through the capacity clause.

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For capacity payments, total energy payments under contracts, which are recoverable through the fuel clause.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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The total period end amount of plant in service and construction in progress net of accumulated depreciation for the utility's share of jointly owned electricity generation plant.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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-Section S99
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The proportionate share of interest (percent) in a jointly owned utility plant.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Number of units of goods that must be purchased within the specified time period of the agreement to avoid penalties or unfavorable effects on pricing, among other adverse consequences.

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No definition available.

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Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
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The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

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-Name Accounting Standards Codification
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Commitments and Contingencies (Long-term Purchase Commitment) (Details) $ in Millions	1 Months Ended	3 Months Ended		6 Months Ended
	Jan. 31, 2018 USD ($) MW	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($) MW	Jun. 30, 2017 USD ($)	Dec. 31, 2017 USD ($)
FPL [Member]
Required capacity and/or minimum payments [Abstract]
Capacity payments		$ 2	$ 20	$ 7	$ 40
Energy payments		8	$ 27	$ 15	$ 43
FPL [Member] \| Pay-for-Performance Contracts [Member]
Long-term Purchase Commitment [Line Items]
Minimum total purchase commitments (in megawatts) \| MW				114
FPL [Member] \| Capacity Charges [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2018		10		$ 10
2019		20		20
2020		20		20
2021		20		20
2022		20		20
Thereafter		225		225
FPL [Member] \| Natural Gas, Including Transportation And Storage, Contract Minimum Payments [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2018		1,075		1,075
2019		1,270		1,270
2020		1,010		1,010
2021		905		905
2022		895		895
Thereafter		11,240		11,240
FPL [Member] \| Coal Contract Minimum Payments [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2018		20		20
2019		5		5
2020		0		0
2021		0		0
2022		0		0
Thereafter		0		0
FPL [Member] \| Take-or-Pay Contract Range 1 [Member]
Required capacity and/or minimum payments [Abstract]
Minimum annual purchase commitments (in megawatts) \| MW	375
FPL [Member] \| Sabal Trail and Florida Southeast Connection [Member] \| Natural Gas, Including Transportation And Storage, Contract Minimum Payments [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2018		150		150
2019		290		290
2020		360		360
2021		390		390
2022		390		390
Thereafter		7,175		7,175
NextEra Energy Resources [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2018		2,175		2,175
2019		830		830
2020		185		185
2021		160		160
2022		175		175
Thereafter		1,335		1,335
NextEra Energy Resources [Member] \| Contract Group 1 [Member]
Long-term Purchase Commitment [Line Items]
Commitment amount included in capital expenditures		3,300		3,300
NextEra Energy Resources [Member] \| Mountain Valley Pipeline [Member]
Required capacity and/or minimum payments [Abstract]
2019		65		65
2020		65		65
2021		65		65
2022		65		65
Thereafter		$ 1,035		$ 1,035
Equity method investment, ownership percentage		31.00%		31.00%
Corporate and Other [Member]
Required capacity and/or minimum payments [Abstract]
Remainder of 2018		$ 275		$ 275
2019		15		15
2020		10		10
2021		10		10
2022		5		5
Thereafter		0		0
Commitment to invest		65		65
Joint Obligations due in the next year		$ 210		$ 210
Jointly Owned Electricity Generation Plant [Member] \| FPL [Member]
Required capacity and/or minimum payments [Abstract]
Public utilities, termination of operations, payment	$ 90
Proportionate ownership percentage	20.00%
Regulatory asset	$ 150
Plant in service, net book value	$ 191
Regulatory asset amortization period (in years)	15 years
Regulatory liabilities						$ 62
Jointly Owned Electricity Generation Plant [Member] \| JEA [Member]
Required capacity and/or minimum payments [Abstract]
Proportionate ownership percentage	80.00%
Jointly Owned Electricity Generation Plant [Member] \| Take-or-Pay Purchased Power Contract [Member] \| FPL [Member]
Required capacity and/or minimum payments [Abstract]
Regulatory asset						$ 90
Jointly Owned Electricity Generation Plant [Member] \| Environmental Cost Recovery [Member] \| FPL [Member]
Required capacity and/or minimum payments [Abstract]
Regulatory asset amortization period (in years)	10 years