Minimum Natural Disaster Reserve Balance, Triggering Establishment Charge

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- Definition

Natural Disaster Reserve Authorized Limit

+ References

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- Definition

Natural Disaster Reserve, Expected Annual Recovery Until Reserve is Restored

+ References

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- Definition

Natural Disaster Reserve, Expected Recovery Amount

+ References

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- Definition

Amount of structure or a modification to a structure under construction. Includes recently completed structures or modifications to structures that have not been placed into service.

+ References

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-Publisher FASB
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- Definition

The proportionate share of interest (percent) in a jointly owned utility plant.

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-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
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Liability as of the balance sheet date for amounts representing estimated cost of settling unpaid claims under the terms of the underlying insurance policies, less estimated reinsurance recoveries on such claims. This includes an estimate for claims which have been incurred but not reported. Claim adjustment expenses represent the costs estimated to be incurred in the settlement of unpaid claims.

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-Topic 944
-SubTopic 210
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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.

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Regulatory Matters - APC (Details) - USD ($)	3 Months Ended	6 Months Ended
Regulatory Matters - APC (Details) - USD ($)	Dec. 31, 2021	Jun. 30, 2021	Apr. 15, 2021	Dec. 31, 2020
Public Utilities, General Disclosures [Line Items]
Construction work in progress		$ 9,264,000,000		$ 8,697,000,000
ALABAMA POWER CO
Public Utilities, General Disclosures [Line Items]
Construction work in progress		978,000,000		866,000,000
Minimum natural disaster reserve balance, triggering establishment charge		50,000,000
Natural disaster reserve authorized limit		75,000,000
Natural disaster reserve balance		36,000,000
Natural disaster reserve, expected annual recovery until reserve is restored		16,000,000
ALABAMA POWER CO \| Scenario, Forecast
Public Utilities, General Disclosures [Line Items]
Natural disaster reserve, expected recovery amount	$ 4,000,000
ALABAMA POWER CO \| Plant Barry Unit 8
Public Utilities, General Disclosures [Line Items]
Construction work in progress		188,000,000
MISSISSIPPI POWER CO
Public Utilities, General Disclosures [Line Items]
Construction work in progress		$ 126,000,000		$ 146,000,000
MISSISSIPPI POWER CO \| Plant Greene County Units 1 and 2 \| ALABAMA POWER CO
Public Utilities, General Disclosures [Line Items]
Proportionate ownership share			40.00%