XML 237 R195.htm IDEA: XBRL DOCUMENT
v3.24.0.1

INCOME TAXES - Amortization of Deferred Credits (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022 | Dec. 31, 2021
Income Tax Disclosure [Line Items] |  |  |
Amortization of investment tax credits | $ 84 | $ 83 | $ 84
Southern Power |  |  |
Income Tax Disclosure [Line Items] |  |  |
Amortization of investment tax credits | $ 58 | $ 58 | $ 58

X
- Definition Amortization of deferred investment tax credits. + References No definition available. + Details
Name: | so_AmortizationOfDeferredInvestmentTaxCredits
Namespace Prefix: | so_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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. + Details
Name: | us-gaap_IncomeTaxContingencyLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=so_SouthernPowerMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |