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Employee Benefit Plans - Narrative (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2025 | Mar. 31, 2024
Defined Benefit Plan Disclosure [Line Items] |  |
Increase (decrease) in regulatory assets and liabilities | $ (1,143) | $ 2,234
GSWC |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Increase (decrease) in regulatory assets and liabilities | (2,767) | 3,935
Pension Benefits |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Plan assets, contributions by employer | 3,400 |
Pension Benefits | GSWC |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Regulatory adjustment — deferred | 800 |
Pension Benefits | Water: | GSWC |  |
Defined Benefit Plan Disclosure [Line Items] |  |
Increase (decrease) in regulatory assets and liabilities | $ (300) | $ (100)

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