Public Utilities, Infrastructure Replacement Programs And Capital Projects, Expenditures

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Public Utilities, Infrastructure Replacement Programs And Capital Projects, Expenditures Since Project Inception

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Public Utilities, Infrastructure Replacement Programs And Capital Projects, Pipe Installed Since Project Inception

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Public Utilities, Infrastructure Replacement Programs And Capital Projects, Program Duration

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Public Utilities, Infrastructure Replacement Programs And Capital Projects, Scope Of Program

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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 - GAS Schedule of Infrastructure Replacement Programs and Capital Projects (Details) - Southern Company Gas $ in Millions	12 Months Ended
	Dec. 31, 2024 USD ($) mi	Dec. 31, 2023 USD ($)	Dec. 31, 2022 USD ($)
Public Utilities, General Disclosures [Line Items]
Capital Expenditures in 2024	$ 186
Capital Expenditures Since Project Inception	$ 868
Pipe Installed Since Project Inception (in miles) \| mi	651
Scope of Program (in miles) \| mi	1,011
SAVE
Public Utilities, General Disclosures [Line Items]
Capital Expenditures in 2024	$ 75
Capital Expenditures Since Project Inception	$ 561
Pipe Installed Since Project Inception (in miles) \| mi	598
Scope of Program (in miles) \| mi	938
Program Duration	18 years
System Reinforcement Rider
Public Utilities, General Disclosures [Line Items]
Capital Expenditures in 2024	$ 99	$ 104	$ 76
Capital Expenditures Since Project Inception	$ 279
Pipe Installed Since Project Inception (in miles) \| mi	29
Program Duration	6 years
Pipeline Replacement Program
Public Utilities, General Disclosures [Line Items]
Capital Expenditures in 2024	$ 12
Capital Expenditures Since Project Inception	$ 28
Pipe Installed Since Project Inception (in miles) \| mi	24
Scope of Program (in miles) \| mi	73
Program Duration	7 years