RATE MATTERS - Regulatory Assets Subject to Securitization (Details) - APPALACHIAN POWER COMPANY $ in Millions	Dec. 31, 2025 USD ($)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	$ 2,528
Undepreciated Utility Plant Balances of Amos, Mitchell and Mountaineer (as of December 31, 2022)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	1,704
ENEC Under-Recovery Regulatory Assets
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	413
Forecasted Undepreciated CCR and ELG Investments of Amos, Mitchell and Mountaineer (as of November 30, 2024)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	237
Deferred Storm Other Operation and Maintenance Expense Regulatory Assets
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	158
Upfront Financing Costs
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	16
APCo
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	1,565
APCo | Undepreciated Utility Plant Balances of Amos, Mitchell and Mountaineer (as of December 31, 2022)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	1,145
APCo | ENEC Under-Recovery Regulatory Assets
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	167
APCo | Forecasted Undepreciated CCR and ELG Investments of Amos, Mitchell and Mountaineer (as of November 30, 2024)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	88
APCo | Deferred Storm Other Operation and Maintenance Expense Regulatory Assets
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	155
APCo | Upfront Financing Costs
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	10
WPCo
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	963
WPCo | Undepreciated Utility Plant Balances of Amos, Mitchell and Mountaineer (as of December 31, 2022)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	559
WPCo | ENEC Under-Recovery Regulatory Assets
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	246
WPCo | Forecasted Undepreciated CCR and ELG Investments of Amos, Mitchell and Mountaineer (as of November 30, 2024)
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	149
WPCo | Deferred Storm Other Operation and Maintenance Expense Regulatory Assets
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	3
WPCo | Upfront Financing Costs
Regulatory Asset [Line Items]
Regulatory asset, requested to be financed through securitization	$ 6