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INCOME TAXES - NOL Carryforwards (Details) $ in Millions | Dec. 31, 2021 USD ($)
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Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | $ 278
Mississippi Power | Mississippi |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 195
Southern Power |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 41
Southern Power | Oklahoma |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 27
Southern Power | Florida |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 10
Southern Power | South Carolina |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 2
Southern Power | Other states |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 2
Other Subsidiaries | Other states |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 17
Other Subsidiaries | New York |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | 11
Other Subsidiaries | New York City |
Operating Loss Carryforwards [Line Items] |
Approximate Net State Income Tax Benefit of NOL Carryforwards | $ 14

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