RATE MATTERS - February 2021 Severe Winter Weather Impacts in SPP (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2025	Dec. 31, 2024	Mar. 31, 2021
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets	$ 4,870.2	$ 5,129.2
SWEPCo
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets	944.9	921.3
February 2021 Severe Storm Fuel Costs \| SWEPCo
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets	144.0	180.5
February 2021 Severe Storm Fuel Costs \| Arkansas \| SWEPCo
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets	$ 29.6	37.2
Approved Recovery Period	6 years
February 2021 Severe Storm Fuel Costs \| Louisiana \| SWEPCo
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets	$ 55.9	70.6
Approved Recovery Period			5 years
February 2021 Severe Storm Fuel Costs \| Texas \| SWEPCo
Public Utilities, General Disclosures [Line Items]
Noncurrent Regulatory Assets	$ 58.5	$ 72.7
Approved Recovery Period	5 years
Approved Carrying Charge	1.65%