Net Regulatory Assets, Estimated Amount Remaining At Retirement

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- Definition

Public Utilities, Required Fossil-stream Generation Retirements

+ References

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 360
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 10.C)
-URI http://asc.fasb.org/extlink&oid=122136288&loc=d3e659983-123033

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 980
-SubTopic 340
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382

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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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REGULATORY MATTERS - MPC Integrated Resource Plan (Details) $ in Millions	Dec. 31, 2021 USD ($)	Sep. 09, 2021 MW	Dec. 31, 2020 USD ($) MW
Public Utilities, General Disclosures [Line Items]
Net regulatory assets \| $	$ 4,711		$ 5,493
Mississippi Power
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs) \| MW			950
Net regulatory assets \| $	46		$ 136
Mississippi Power \| Plant Watson Unit 4
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs) \| MW		268
Mississippi Power \| Plant Greene County Units 1 and 2
Public Utilities, General Disclosures [Line Items]
Required fossil-stream generation retirements (in MWs) \| MW		103
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) \| MW		502
Percent ownership		50.00%
Net regulatory assets \| $	515
Estimated amount remaining at retirement \| $	$ 386