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v3.25.2

Employee Benefit Plans (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Pension plans |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | $ 6 | $ 6 | $ 12 | $ 12
Interest cost | 19 | 18 | 39 | 37
Expected return on plan assets | (20) | (18) | (40) | (37)
Amortization of net loss | 7 | 7 | 14 | 14
Net periodic cost (benefit) | 12 | 13 | 25 | 26
Total contributions expected in current year | 116 |  | 116 |
Total contributions to the plans during the period | 17 |  | 80 |
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 | 0 | 1 | 0 | 1
Interest cost | 4 | 3 | 7 | 6
Expected return on plan assets | (2) | (2) | (3) | (3)
Amortization of prior service cost (credit) | 0 | 0 | (1) | (1)
Amortization of net loss | (3) | (2) | (5) | (4)
Net periodic cost (benefit) | (1) | 0 | (2) | (1)
Total contributions expected in current year | 9 |  | 9 |
Total contributions to the plans during the period | 4 |  | 7 |
Postretirement benefit plans | Houston Electric |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 2 | 2 | 3 | 3
Expected return on plan assets | (1) | (1) | (2) | (2)
Amortization of prior service cost (credit) | (1) | (2) | (2) | (3)
Amortization of net loss | (2) | (1) | (3) | (2)
Net periodic cost (benefit) | (2) | (2) | (4) | (4)
Total contributions expected in current year | 1 |  | 1 |
Total contributions to the plans during the period | 1 |  | 1 |
Postretirement benefit plans | CERC |  |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |  |
Service cost | 0 | 0 | 0 | 0
Interest cost | 1 | 1 | 2 | 2
Expected return on plan assets | (1) | 0 | (1) | 0
Amortization of prior service cost (credit) | 0 | 0 | 1 | 1
Amortization of net loss | (1) | 0 | (2) | (1)
Net periodic cost (benefit) | (1) | $ 1 | 0 | $ 2
Total contributions expected in current year | 5 |  | 5 |
Total contributions to the plans during the period | $ 2 |  | $ 4 |

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