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Infrastructure Replacement Program, Approved Investment Variance Amount

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Public Utilities, Approved Annual Recovery of Capital Investment

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

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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 - Southern Company Gas (Details) - USD ($) $ in Millions	Jul. 31, 2024	Jul. 02, 2024	Jun. 07, 2024
SOUTHERN Co GAS \| SAVE
Public Utilities, General Disclosures [Line Items]
Approved investment amount			$ 355
Approved investment variance amount			$ 5
Program duration period			5 years
SOUTHERN Co GAS \| SAVE \| 2025
Public Utilities, General Disclosures [Line Items]
Approved investment amount			$ 70
SOUTHERN Co GAS \| SAVE \| 2026
Public Utilities, General Disclosures [Line Items]
Approved investment amount			70
SOUTHERN Co GAS \| SAVE \| 2027
Public Utilities, General Disclosures [Line Items]
Approved investment amount			70
SOUTHERN Co GAS \| SAVE \| 2028
Public Utilities, General Disclosures [Line Items]
Approved investment amount			70
SOUTHERN Co GAS \| SAVE \| 2029
Public Utilities, General Disclosures [Line Items]
Approved investment amount			$ 70
Atlanta Gas Light \| Subsequent Event
Public Utilities, General Disclosures [Line Items]
Recovery of capital investments		$ 600
Approved rate increase (decrease)	$ 120