CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - SWEPCo (Parenthetical) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Amortization of Pension and OPEB Deferred Costs, Tax	$ 0	$ (1)	$ (3)
Pension and OPEB Funded Status, Tax	17	11	(4)
SOUTHWESTERN ELECTRIC POWER COMPANY
Amortization of Pension and OPEB Deferred Costs, Tax	0	0	0
Pension and OPEB Funded Status, Tax	$ 1	$ 2	$ 1

Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 12
-SubTopic 10
-Topic 220
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482790/220-10-45-12

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Balance Type:	debit
Period Type:	duration