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

Fair market value of fund's securities on loan under fund's managers securities lending program.

+ References

No definition available.

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- Definition

Fair value of collateral received amount.

+ References

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- Definition

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

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 25
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=116646717&loc=d3e6290-110844

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)(4)
-URI https://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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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
	Jan. 01, 2023	Dec. 31, 2022	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2019	Dec. 31, 2020
Jointly Owned Utility Plant Interests [Line Items]
Cash flow revisions			$ (834,000,000)	$ 1,026,000,000
Asset retirement obligations		$ 10,840,000,000	10,840,000,000	11,687,000,000		$ 10,684,000,000
Alabama Power
Jointly Owned Utility Plant Interests [Line Items]
Cash flow revisions			$ 0	406,000,000
Estimated inflation rate			4.50%
Estimated trust earnings rate			7.00%
Asset retirement obligations		4,287,000,000	$ 4,287,000,000	4,334,000,000		3,974,000,000
Alabama Power \| Internal reserves
Jointly Owned Utility Plant Interests [Line Items]
Accumulated provisions for decommissioning		14,000,000	$ 14,000,000	15,000,000
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]
Cash flow revisions			$ (844,000,000)	530,000,000
Fair market value of securities on loan and pledged to creditors		35,000,000	35,000,000	42,000,000
Fair value of collateral received		36,000,000	$ 36,000,000	43,000,000
Estimated inflation rate			2.50%
Estimated trust earnings rate			4.50%
Asset retirement obligations		6,034,000,000	$ 6,034,000,000	6,824,000,000		6,265,000,000
Georgia Power \| CCR AROs
Jointly Owned Utility Plant Interests [Line Items]
Cash flow revisions		(780,000,000)		435,000,000
Georgia Power \| Plant Hatch and Plant Vogtle Units 1 And 2
Jointly Owned Utility Plant Interests [Line Items]
Annual decommissioning cost for ratemaking					$ 4,000,000
Georgia Power \| Plant Hatch and Plant Vogtle Units 1 And 2 \| Scenario, Forecast
Jointly Owned Utility Plant Interests [Line Items]
Annual decommissioning cost for ratemaking	$ 0
Mississippi Power
Jointly Owned Utility Plant Interests [Line Items]
Cash flow revisions			3,000,000	31,000,000
Asset retirement obligations		$ 179,000,000	$ 179,000,000	$ 190,000,000		$ 176,000,000