Regulatory Matters - GPC Storm Damage Recovery (Details) - USD ($) $ in Millions	1 Months Ended	9 Months Ended
Aug. 31, 2023	Sep. 30, 2023
Accrued Storm Reserve
Public Utilities, General Disclosures [Line Items]
Accrual		$ 42
GEORGIA POWER CO
Public Utilities, General Disclosures [Line Items]
Weather-related damages		31
Regulatory balance		97
GEORGIA POWER CO \| Accrued Storm Reserve
Public Utilities, General Disclosures [Line Items]
Accrual	$ 110	24
ALABAMA POWER CO \| Accrued Storm Reserve
Public Utilities, General Disclosures [Line Items]
Accrual		$ 9

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- Definition

Amount, after effects of reinsurance, of increase (decrease) in the liability for unpaid claims and claims adjustment expense.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 944
-SubTopic 40
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480081/944-40-50-3

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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

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- Definition

The amount for the individual regulatory liability as itemized in a table of regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 405
-Name Accounting Standards Codification
-Section 25
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147481854/980-405-25-1

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