Asset Retirement Obligations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Asset retirement obligation, roll forward analysis [Roll Forward]
Beginning balance	$ 3,135	$ 3,031
Liabilities incurred	100	49
Accretion expense	172	158
Liabilities settled	(65)	(26)
Revision in estimated cash flows - net	32	4
Impact of NEP deconsolidation		(81)
Additions from acquisitions	132
Ending balance	3,506	3,135
Current portion	49
Restricted funds included in special use funds [Abstract]
Restricted funds	6,880	5,818
FPL[Member]
Asset retirement obligation, roll forward analysis [Roll Forward]
Beginning balance	2,147	2,047
Liabilities incurred	1	0
Accretion expense	107	101
Liabilities settled	(1)	(1)
Revision in estimated cash flows - net	14	0
Impact of NEP deconsolidation		0
Additions from acquisitions	0
Ending balance	2,268	2,147
Increase (decrease) in asset retirement obligation	$ (71)
License renewal period	20 years
Restricted funds included in special use funds [Abstract]
Restricted funds	$ 4,697	$ 3,987
FPL[Member] \| Jointly Owned Electricity Generation Plant 1 Member
Asset retirement obligation, roll forward analysis [Roll Forward]
Increase (decrease) in asset retirement obligation	$ 75

Asset Retirement Obligation, Additions From Acquisitions

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Asset Retirement Obligation, Impact Of Deconsolidation

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License Renewal Period

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The carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Amount of accretion expense recognized during the period that is associated with an asset retirement obligation. Accretion expense measures and incorporates changes due to the passage of time into the carrying amount of the liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(3)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6392676&loc=d3e7480-110848

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Current portion of the carrying amount of a liability for an asset retirement obligation. An asset retirement obligation is a legal obligation associated with the disposal or retirement of a tangible long-lived asset that results from the acquisition, construction or development, or the normal operations of a long-lived asset, except for certain obligations of lessees.

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Carrying amount of an asset that is legally restricted for purposes of settling an asset retirement obligation.

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Amount of asset retirement obligations incurred during the period.

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Amount of asset retirement obligations settled, or otherwise disposed of, during the period. This may include asset retirement obligations transferred to third parties associated with the sale of a long-lived asset.

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Amount of increase (decrease) in asset retirement obligations.

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Amount of increase (decrease) in the asset retirement obligation from changes in the amount or timing of the estimated cash flows associated with the settlement of the obligation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 35
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=6392603&loc=d3e7123-110846

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-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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