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Revenue from Contracts with Customers and Lease Income - Schedule of Remaining Performance Obligations (Details) $ in Millions | Sep. 30, 2024 USD ($)
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Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 303
Performance obligation, expected timing of satisfaction | 3 months
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 884
Performance obligation, expected timing of satisfaction | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 375
Performance obligation, expected timing of satisfaction | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 336
Performance obligation, expected timing of satisfaction | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 325
Performance obligation, expected timing of satisfaction | 1 year
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 2,180
Performance obligation, expected timing of satisfaction |
ALABAMA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 11
Performance obligation, expected timing of satisfaction | 3 months
ALABAMA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 11
Performance obligation, expected timing of satisfaction | 1 year
ALABAMA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction | 1 year
ALABAMA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction | 1 year
ALABAMA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction | 1 year
ALABAMA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction |
GEORGIA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 21
Performance obligation, expected timing of satisfaction | 3 months
GEORGIA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 64
Performance obligation, expected timing of satisfaction | 1 year
GEORGIA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 26
Performance obligation, expected timing of satisfaction | 1 year
GEORGIA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 17
Performance obligation, expected timing of satisfaction | 1 year
GEORGIA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 17
Performance obligation, expected timing of satisfaction | 1 year
GEORGIA POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 17
Performance obligation, expected timing of satisfaction |
MISSISSIPPI POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 15
Performance obligation, expected timing of satisfaction | 3 months
MISSISSIPPI POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 63
Performance obligation, expected timing of satisfaction | 1 year
MISSISSIPPI POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 66
Performance obligation, expected timing of satisfaction | 1 year
MISSISSIPPI POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 69
Performance obligation, expected timing of satisfaction | 1 year
MISSISSIPPI POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 73
Performance obligation, expected timing of satisfaction | 1 year
MISSISSIPPI POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction |
SOUTHERN POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 73
Performance obligation, expected timing of satisfaction | 3 months
SOUTHERN POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 312
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 299
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 306
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 297
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN POWER CO | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 2,169
Performance obligation, expected timing of satisfaction |
SOUTHERN Co GAS | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-10-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 3
Performance obligation, expected timing of satisfaction | 3 months
SOUTHERN Co GAS | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 2
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN Co GAS | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN Co GAS | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN Co GAS | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2028-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction | 1 year
SOUTHERN Co GAS | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2029-01-01 |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items] |
Revenue, remaining performance obligation | $ 0
Performance obligation, expected timing of satisfaction |

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