DERIVATIVES AND HEDGING - Narrative (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Cash collateral received from third-parties	$ 83	$ 87
Fair value of derivative liability subject to cross-acceleration	30	72
Fair value of derivative liability, subject to cross-default provision	183	164
APCo
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair value of derivative liability, subject to cross-default provision	2	1
PSO
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair value of derivative liability, subject to cross-default provision	27	4
SWEPCo
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Fair value of derivative liability, subject to cross-default provision	$ 10	$ 2
Commodity
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Maximum length of time to hedge exposure to variability	9 years
Cross-acceleration provisions, maximum third-party obligation, amount	$ 50
Cross-default trigger, maximum third party obligation, amount	$ 50