FINANCING ACTIVITIES - Schedule of Short-term Debt (Details) - USD ($) $ in Millions |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Short-Term Debt [Line Items] | ||
| Short-term – Securitized Debt of Receivables | $ 900 | $ 900 |
| Interest Rate | 3.95% | 4.00% |
| Commercial Paper | $ 1,125 | $ 605 |
| Total Short-term Debt | 2,028 | 1,508 |
| SOUTHWESTERN ELECTRIC POWER COMPANY | ||
| Short-Term Debt [Line Items] | ||
| Notes Payable | $ 3 | $ 3 |
| Commercial Paper | ||
| Short-Term Debt [Line Items] | ||
| Weighted-Average Interest Rate | 4.07% | 3.92% |
| Notes Payable | SOUTHWESTERN ELECTRIC POWER COMPANY | ||
| Short-Term Debt [Line Items] | ||
| Weighted-Average Interest Rate | 6.00% | 6.30% |
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- Definition Carrying value as of the balance sheet date of short-term borrowings using unsecured obligations issued by banks, corporations and other borrowers to investors. The maturities of these money market securities generally do not exceed 270 days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average interest rate of debt outstanding. No definition available.
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- Definition Including the current and noncurrent portions, aggregate carrying amount of all types of notes payable, as of the balance sheet date, with initial maturities beyond one year or beyond the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Weighted average interest rate of short-term debt outstanding calculated at point in time. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented. No definition available.
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