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v3.25.3

Employee Benefit Plans (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Pension plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | $ 5 | $ 6 | $ 17 | $ 18
Interest cost | 20 | 18 | 59 | 55
Expected return on plan assets | (20) | (19) | (60) | (56)
Amortization of net loss | 7 | 7 | 21 | 21
Net periodic cost (benefit) | 12 | 12 | 37 | 38
Total contributions expected in current year | 116 |  | 116 |
Total contributions to the plans during the period | 21 |  | 101 |
Pension plans | Houston Electric |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Total contributions expected in current year | 0 |  | 0 |
Total contributions to the plans during the period | 0 |  | 0 |
Pension plans | CERC |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Total contributions expected in current year | 0 |  | 0 |
Total contributions to the plans during the period | 0 |  | 0 |
Postretirement benefit plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 1 | 0 | 1 | 1
Interest cost | 3 | 3 | 10 | 9
Expected return on plan assets | (1) | (1) | (4) | (4)
Amortization of prior service cost (credit) | (1) | (1) | (2) | (2)
Amortization of net loss | (2) | (2) | (7) | (6)
Net periodic cost (benefit) | 0 | (1) | (2) | (2)
Total contributions expected in current year | 10 |  | 10 |
Total contributions to the plans during the period | 3 |  | 10 |
Postretirement benefit plans | Houston Electric |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 1 | 1 | 4 | 4
Expected return on plan assets | (1) | (1) | (3) | (3)
Amortization of prior service cost (credit) | (2) | (1) | (4) | (4)
Amortization of net loss | (1) | (1) | (4) | (3)
Net periodic cost (benefit) | (3) | (2) | (7) | (6)
Total contributions expected in current year | 1 |  | 1 |
Total contributions to the plans during the period | 0 |  | 1 |
Postretirement benefit plans | CERC |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 2 | 1 | 4 | 3
Expected return on plan assets | 0 | (1) | (1) | (1)
Amortization of prior service cost (credit) | 1 | 1 | 2 | 2
Amortization of net loss | (1) | (1) | (3) | (2)
Net periodic cost (benefit) | 2 | $ 0 | 2 | $ 2
Total contributions expected in current year | 6 |  | 6 |
Total contributions to the plans during the period | $ 2 |  | $ 6 |

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