v3.25.4

Exit Activities and Asset Sales (Narrative) (Details) $ in Millions | 1 Months Ended | 12 Months Ended | 42 Months Ended |
--- | --- | --- | --- | ---
Sep. 30, 2025 facility | Dec. 31, 2025 USD ($) | Dec. 31, 2024 USD ($) | Nov. 30, 2025 USD ($) | Feb. 17, 2026 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Facilities agreed to sell | facility | 13 |  |  |  |
Duration of purchase agreement | 30 years |  |  |  |
Minimum |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Expected duration of review | 12 months |  |  |  |
Maximum |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Expected duration of review | 18 months |  |  |  |
Retention Benefits |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Retention and severance costs |  | $ 7 | $ 8 |  |
Retention Benefits | D.E. Karn Generating Complex and J.H. Campbell Generating Units | Retention Incentive Program |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Regulatory asset collection period |  | 3 years |  |  |
Retention Benefits | J.H. Campbell Generating Units |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Retention and severance costs |  |  |  | $ 48 |
Retention Benefits | J.H. Campbell Generating Units | Subsequent Event |  |  |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |  |  |
Expected cost |  |  |  |  | $ 4

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