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v3.25.3

Fair Value Measurements - Schedule of Assets and Liabilities Measured On Recurring Basis (Details) - Fair Value, Recurring - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Assets |  |
Equity securities | $ 579 | $ 561
Investments, including money market funds | 22 | 22
Total assets | 601 | 583
Liabilities |  |
Total liabilities | 635 | 619
Houston Electric |  |
Assets |  |
Investments, including money market funds | 5 | 5
Total assets | 5 | 5
CERC |  |
Assets |  |
Investments, including money market funds | 16 | 15
Total assets | 16 | 15
Indexed debt securities derivative |  |
Liabilities |  |
Derivative liability | 635 | 619
Level 1 |  |
Assets |  |
Equity securities | 579 | 561
Investments, including money market funds | 22 | 22
Total assets | 601 | 583
Liabilities |  |
Total liabilities | 0 | 0
Level 1 | Houston Electric |  |
Assets |  |
Investments, including money market funds | 5 | 5
Total assets | 5 | 5
Level 1 | CERC |  |
Assets |  |
Investments, including money market funds | 16 | 15
Total assets | 16 | 15
Level 1 | Indexed debt securities derivative |  |
Liabilities |  |
Derivative liability | 0 | 0
Level 2 |  |
Assets |  |
Equity securities | 0 | 0
Investments, including money market funds | 0 | 0
Total assets | 0 | 0
Liabilities |  |
Total liabilities | 635 | 619
Level 2 | Houston Electric |  |
Assets |  |
Investments, including money market funds | 0 | 0
Total assets | 0 | 0
Level 2 | CERC |  |
Assets |  |
Investments, including money market funds | 0 | 0
Total assets | 0 | 0
Level 2 | Indexed debt securities derivative |  |
Liabilities |  |
Derivative liability | 635 | 619
Level 3 |  |
Assets |  |
Equity securities | 0 | 0
Investments, including money market funds | 0 | 0
Total assets | 0 | 0
Liabilities |  |
Total liabilities | 0 | 0
Level 3 | Houston Electric |  |
Assets |  |
Investments, including money market funds | 0 | 0
Total assets | 0 | 0
Level 3 | CERC |  |
Assets |  |
Investments, including money market funds | 0 | 0
Total assets | 0 | 0
Level 3 | Indexed debt securities derivative |  |
Liabilities |  |
Derivative liability | $ 0 | $ 0

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