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

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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

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) - USD ($)				1 Months Ended				12 Months Ended
	May 01, 2024	Aug. 01, 2023	Jan. 01, 2023	Nov. 30, 2025	Jun. 30, 2025	Nov. 30, 2024	Sep. 30, 2024	Dec. 31, 2025	Dec. 31, 2024	Feb. 14, 2024	Dec. 31, 2023
Jointly Owned Utility Plant Interests [Line Items]
Asset retirement obligations								$ 9,601,000,000	$ 9,934,000,000		$ 10,317,000,000
Plant Vogtle Unit 4
Jointly Owned Utility Plant Interests [Line Items]
Asset retirement obligations										$ 118,000,000
Alabama Power
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to ARO					$ (257,000,000)
Asset retirement obligations								3,679,000,000	4,058,000,000		4,158,000,000
Alabama Power \| Internal reserves
Jointly Owned Utility Plant Interests [Line Items]
Accumulated provisions for decommissioning								$ 11,000,000	12,000,000
Alabama Power \| Plant Farley
Jointly Owned Utility Plant Interests [Line Items]
Estimated inflation rate								4.50%
Estimated trust earnings rate								7.00%
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]
Increase (decrease) to ARO				$ 200,000,000		$ 60,000,000	$ (389,000,000)
Asset retirement obligations								$ 5,527,000,000	5,415,000,000		5,665,000,000
Georgia Power \| Plant Hatch
Jointly Owned Utility Plant Interests [Line Items]
Estimated inflation rate								2.50%
Estimated trust earnings rate								4.50%
Georgia Power \| Plant Vogtle Units 3 and 4
Jointly Owned Utility Plant Interests [Line Items]
Estimated inflation rate								2.30%
Estimated trust earnings rate								4.30%
Georgia Power \| Plant Hatch and Plant Vogtle Units 1 And 2
Jointly Owned Utility Plant Interests [Line Items]
Annual decommissioning cost for ratemaking			$ 0
Georgia Power \| Plant Vogtle Units 3 and 4
Jointly Owned Utility Plant Interests [Line Items]
Annual decommissioning cost for ratemaking		$ 8,000,000
Georgia Power \| Plant Vogtle Unit 4
Jointly Owned Utility Plant Interests [Line Items]
Annual decommissioning cost for ratemaking	$ 8,000,000
Mississippi Power
Jointly Owned Utility Plant Interests [Line Items]
Increase (decrease) to ARO					$ (13,000,000)
Asset retirement obligations								$ 124,000,000	$ 148,000,000		$ 168,000,000