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v3.25.1

Securitization - Narrative (Details) - USD ($) $ in Thousands | 1 Months Ended |  |  |
--- | --- | --- | --- | ---
Mar. 31, 2023 | Mar. 31, 2025 | Sep. 30, 2024 | Jun. 30, 2023
Variable Interest Entity [Line Items] |  |  |  |
Long-term debt, fair value |  | $ 7,568,621 | $ 7,337,936 |
Variable Interest Entity, Primary Beneficiary | Texas | Extraordinary Gas Cost | Winter Storm Uri |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Regulatory asset, authorized | $ 3,500,000 |  |  |
Variable Interest Entity, Primary Beneficiary | Texas | Extraordinary Gas Cost | Winter Storm Uri | Minimum |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Regulatory asset, maturity period | 12 years |  |  |
Variable Interest Entity, Primary Beneficiary | Texas | Extraordinary Gas Cost | Winter Storm Uri | Maximum |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Regulatory asset, maturity period | 18 years |  |  |
Securitized Utility Tariff Bonds | Senior Notes | Variable Interest Entity, Primary Beneficiary |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Debt face amount |  |  |  | $ 95,000
Long-term debt |  | 81,000 | 85,100 |
Long-term debt, fair value |  | $ 81,900 | $ 87,800 |

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