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v3.25.1

Revenue Customer Type (Details) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Mar. 31, 2025 USD ($) Units | Mar. 31, 2024 USD ($) | Mar. 31, 2025 USD ($) Units | Mar. 31, 2024 USD ($)
Revenue, Major Customer [Line Items] |  |  |  |
MLGW's % of operating revenues |  |  | 700.00% | 700.00%
NES's % of operating revenues |  |  | 800.00% | 800.00%
Off System Sales of Electricity | $ 1 | $ 2 | $ 2 | $ 4
Bill credits for LTA | $ (61) | $ (54) | $ (111) | (101)
Number of LPCs signed LTA | Units | 148 |  | 148 |
Number of LPCs signed Flexibility Agreement | Units | 107 |  | 107 |
Percent of sales of electricity to LPCs |  | 92.00% | 92.00% |
Pre-commercial Ops - capitalized revenue | $ (2) | $ 0 | $ (2) | 3
Regulated Operating Revenue | 3,476 | 3,093 | 6,352 | 5,824
Unregulated Operating Revenue | 56 | 61 | 100 | 95
Regulated and Unregulated Operating Revenue | 3,532 | 3,154 | 6,452 | 5,919
lpcs [Domain] |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 3,199 | 2,842 | 5,815 | 5,329
industries directly served [Domain] |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 245 | 221 | 475 | 438
federal agencies and other [Domain] |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 34 | 30 | 64 | 60
ALABAMA |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 520 | 457 | 951 | 865
GEORGIA |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 94 | 80 | 168 | 149
KENTUCKY |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 214 | 201 | 396 | 378
MISSISSIPPI |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 307 | 284 | 576 | 539
NORTH CAROLINA |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 28 | 28 | 49 | 51
TENNESSEE |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | 2,298 | 2,027 | 4,184 | 3,816
VIRGINIA |  |  |  |
Revenue, Major Customer [Line Items] |  |  |  |
Regulated Operating Revenue | $ 16 | $ 14 | $ 28 | $ 25

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- Definition MLGW's % of operating revenues + References No definition available. + Details
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- Definition NES's % of operating revenues + References No definition available. + Details
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