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- Definition

Public Utilities, Approved Additional Generating Capacity

+ References

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Public Utilities, Review Period

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 360
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479070/980-360-S99-1

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- Definition

The net amount of all regulatory assets less all regulatory liabilities as of the end of the period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 980
-SubTopic 340
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478742/980-340-50-1

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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.

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REGULATORY MATTERS - MPC Integrated Resource Plan (Details) $ in Millions			1 Months Ended
	Jan. 09, 2025 MW	Apr. 26, 2024	Oct. 31, 2023 MW	Dec. 31, 2024 USD ($)	Nov. 08, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2021 MW	Dec. 31, 2020 MW
Public Utilities, General Disclosures [Line Items]
Net regulatory assets \| $				$ 7,041		$ 6,523
Mississippi Power
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs)								950
Approved additional generating capacity (in MW)			750
Review period		120 days
Net regulatory assets \| $				$ 59		$ 90
Mississippi Power \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Approved additional generating capacity (in MW)	600
Mississippi Power \| Plant Watson Unit 4
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs)							268
Mississippi Power \| Plant Greene County Units 1 and 2
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs)							206
Percent ownership				40.00%
Mississippi Power \| Plant Greene County Units 1 and 2 \| Alabama Power
Public Utilities, General Disclosures [Line Items]
Percent ownership							40.00%
Mississippi Power \| Plant Daniel
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs)							502
Percent ownership		50.00%					50.00%
Net regulatory assets \| $				$ 478
Mississippi Power \| Plant Daniel \| Minimum
Public Utilities, General Disclosures [Line Items]
Acquisition payment receivable \| $					$ 35
Mississippi Power \| Plant Daniel \| Maximum
Public Utilities, General Disclosures [Line Items]
Acquisition payment receivable \| $					$ 38