Accumulated Provisions for Decommissioning.

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- Definition

Amount expensed for rate making purpose.

+ References

No definition available.

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- Definition

Asset Retirement Obligation, Frequency Of Decommissioning Costs Estimates

+ References

No definition available.

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- Definition

Public Utilities, Approved Change In Method of Closure, Number Of Ash Ponds

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- Definition

Significant Assumption Of Inflation Rate Used To Determine Costs For Rate Making

+ References

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- Definition

Significant Assumption Of Trust Earnings Rate Used To Determine Costs For Rate Making

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 25
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481999/410-20-25-4

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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- Definition

Amount of increase (decrease) in asset retirement obligations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 410
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481850/410-20-50-1

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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.

+ References

No definition available.

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ASSET RETIREMENT OBLIGATIONS - Narrative (Details)		1 Months Ended				12 Months Ended
ASSET RETIREMENT OBLIGATIONS - Narrative (Details)	Aug. 01, 2023 USD ($)	Nov. 30, 2023 USD ($)	Sep. 30, 2023 USD ($)	Jun. 30, 2023 USD ($)	Dec. 31, 2022 USD ($) ashPond	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($) ashPond	Dec. 31, 2019 USD ($)	Feb. 14, 2024 USD ($)	Mar. 06, 2023 USD ($)	Dec. 31, 2021 USD ($)
Jointly Owned Utility Plant Interests [Line Items]
Revision to ARO						$ (399,000,000)	$ (834,000,000)
Asset retirement obligations					$ 10,840,000,000	10,317,000,000	10,840,000,000				$ 11,687,000,000
Plant Vogtle Units 3 and 4
Jointly Owned Utility Plant Interests [Line Items]
Asset retirement obligations										$ 90,000,000
Plant Vogtle Unit 4 \| Scenario, Forecast
Jointly Owned Utility Plant Interests [Line Items]
Asset retirement obligations									$ 118,000,000
Alabama Power
Jointly Owned Utility Plant Interests [Line Items]
Revision to ARO						(15,000,000)	0
Asset retirement obligations					4,287,000,000	$ 4,158,000,000	4,287,000,000				4,334,000,000
Asset Retirement Obligation, Period Increase (Decrease)				$ 15,000,000
Estimated inflation rate						4.50%
Estimated trust earnings rate						7.00%
Alabama Power \| Internal reserves
Jointly Owned Utility Plant Interests [Line Items]
Accumulated provisions for decommissioning					$ 14,000,000	$ 13,000,000	14,000,000
Alabama Power \| Plant Farley
Jointly Owned Utility Plant Interests [Line Items]
Site-specific estimate of decommissioning costs, period of updates made						5 years
Georgia Power
Jointly Owned Utility Plant Interests [Line Items]
Revision to ARO						$ (385,000,000)	$ (844,000,000)
Number of ash ponds \| ashPond					1		1
Asset retirement obligations					$ 6,034,000,000	$ 5,665,000,000	$ 6,034,000,000				6,824,000,000
Asset Retirement Obligation, Period Increase (Decrease)		$ 210,000,000	$ 175,000,000
Estimated inflation rate						2.50%
Estimated trust earnings rate						4.50%
Georgia Power \| CCR AROs
Jointly Owned Utility Plant Interests [Line Items]
Revision to ARO					(780,000,000)
Georgia Power \| Plant Hatch and Plant Vogtle Units 1 And 2
Jointly Owned Utility Plant Interests [Line Items]
Annual decommissioning cost for ratemaking							0	$ 4,000,000
Georgia Power \| Plant Vogtle Units 3 and 4
Jointly Owned Utility Plant Interests [Line Items]
Estimated inflation rate						2.40%
Estimated trust earnings rate						4.40%
Annual decommissioning cost for ratemaking	$ 8,000,000
Mississippi Power
Jointly Owned Utility Plant Interests [Line Items]
Revision to ARO						$ 2,000,000	3,000,000
Asset retirement obligations					$ 179,000,000	$ 168,000,000	$ 179,000,000				$ 190,000,000