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INCOME TAXES - NOL Carryforwards (Details) $ in Millions | Dec. 31, 2024 USD ($)
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Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | $ 265
Operating loss carryforwards, valuation allowance | (82)
Mississippi Power | Mississippi |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 178
Operating loss carryforwards, valuation allowance | (32)
Southern Power |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 38
Operating loss carryforwards, valuation allowance | (21)
Southern Power | Oklahoma |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 26
Operating loss carryforwards, valuation allowance | (11)
Southern Power | Florida |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 10
Operating loss carryforwards, valuation allowance | (10)
Southern Power | Other states |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 2
Operating loss carryforwards, valuation allowance | 0
Other Subsidiaries | Other states |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 24
Operating loss carryforwards, valuation allowance | (4)
Other Subsidiaries | New York |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 11
Operating loss carryforwards, valuation allowance | (11)
Other Subsidiaries | New York City |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 14
Operating loss carryforwards, valuation allowance | $ (14)

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- Definition Amount before allocation of valuation allowances of deferred tax asset attributable to deductible state and local operating loss carryforwards. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 6 -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-6 + 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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 3 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-3 + Details
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- Definition The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 740 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 2 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org/1943274/2147482685/740-10-50-2 + Details
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