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v3.25.3

RATE MATTERS - Net Book Value (Details) - Generating Units Probable of Abandonment - SWEPCo $ in Millions | 9 Months Ended
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Sep. 30, 2025 USD ($)
Northeastern Plant, Unit 3 |
Public Utilities, General Disclosures [Line Items] |
Net Book Value | $ 73.9
Accelerated Depreciation Regulatory Asset | 212.8
Cost of Removal Regulatory Liability | 21.2
Annual Depreciation | 16.1
Welsh Plant, Units 1 and 3 |
Public Utilities, General Disclosures [Line Items] |
Net Book Value | 278.8
Accelerated Depreciation Regulatory Asset | 206.2
Cost of Removal Regulatory Liability | 57.6
Annual Depreciation | $ 46.5

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