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INCOME TAXES - Amortization of Deferred Credits (Details) - USD ($) $ in Millions | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Tax Disclosure [Line Items] |  |  |
Amortization of deferred investment tax credits | $ 84 | $ 84 | $ 181
Southern Power |  |  |
Income Tax Disclosure [Line Items] |  |  |
Amortization of deferred investment tax credits | $ 58 | $ 59 | $ 151

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- Definition Amortization of deferred investment tax credits. + References No definition available. + Details
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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. + Details
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- Details
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Namespace Prefix: |
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Balance Type: |
Period Type: |