RATE MATTERS - Regulated Generating Units (Details) $ in Millions	Mar. 31, 2025 USD ($)
Pirkey Generating Station (Unit No. 1) \| SWEPCo \| Texas
Public Utilities, General Disclosures [Line Items]
Net book value	$ 69

Amount after accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business to produce goods and services and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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