Proceeds From Asset Acquisition, Transaction Cost Reimbursement

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Public Utilities, Approved Rate Increase (Decrease), Minimum Annual Accrual, Amount

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Public Utilities, Customer Refund Payments

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- Definition

Regulatory Asset, Accrual

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- Definition

Regulatory Clause, Property Damage Reserve

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- Definition

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

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

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

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Percentage of public utility's approved rate increase (decrease) by regulatory agency.

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Amount of public utility's requested rate increase (decrease) with regulatory agency.

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Percentage of public utility's requested rate increase (decrease) with regulatory agency.

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Regulatory Matters - MPC (Details) - MISSISSIPPI POWER CO - USD ($)								1 Months Ended
	Jul. 30, 2025	Jun. 30, 2025	Jun. 17, 2025	Apr. 03, 2025	Apr. 01, 2025	Mar. 17, 2025	Apr. 11, 2024	Jul. 31, 2025	Apr. 30, 2025	Jun. 19, 2025	Jun. 16, 2025
Loss Contingencies [Line Items]
Approved rate increase (decrease)					$ 8,000,000
Plant Daniel Units 1 and 2
Loss Contingencies [Line Items]
Proportionate ownership share										50.00%
Reliability Reserve Liability
Loss Contingencies [Line Items]
Accrual						$ (10,900,000)
Remaining net book value						$ 57,000,000
Subsequent Event \| Plant Daniel Units 1 and 2
Loss Contingencies [Line Items]
Proceeds from acquisition	$ 36,000,000
Mississippi PSC PEP Filing
Loss Contingencies [Line Items]
Requested revenues increase (decrease) percentage			4.00%
Requested rate increase amount			$ 41,000,000
Approved rate increase, percentage			2.00%
Approved rate increase (decrease)									$ 22,000,000
Mississippi PSC PEP Filing \| Subsequent Event
Loss Contingencies [Line Items]
Approved rate increase (decrease)								$ 19,000,000
Mississippi PSC
Loss Contingencies [Line Items]
Approved rate increase (decrease)					$ 6,000,000
Ad Valorem Tax Adjustment
Loss Contingencies [Line Items]
Requested rate increase amount		$ 7,000,000
Mississippi PSC SRR Filing
Loss Contingencies [Line Items]
Approved rate increase (decrease)			$ 13,500,000
Minimum annual accrual, amount							$ 12,600,000
Property damage reserve			$ 125,000,000								$ 75,000,000
FERC
Loss Contingencies [Line Items]
Approved rate increase, percentage				2.50%
Approved rate increase (decrease)				$ 1,000,000
Customer refund payments				$ 4,000,000