Fair Value of Financial Instruments - Schedule of Outstanding Long-Term Debt (Details) - USD ($) $ in Thousands |
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Fair value of financial instruments | ||
| Unamortized debt issuance expense | $ 3,200 | $ 3,400 |
| Carrying Amount | ||
| Fair value of financial instruments | ||
| Long-term debt, fair value | 794,185 | 794,310 |
| Fair Value | ||
| Fair value of financial instruments | ||
| Long-term debt, fair value | 776,792 | 790,820 |
| GOLDEN STATE WATER COMPANY | ||
| Fair value of financial instruments | ||
| Unamortized debt issuance expense | 2,900 | 3,000 |
| GOLDEN STATE WATER COMPANY | Carrying Amount | ||
| Fair value of financial instruments | ||
| Long-term debt, fair value | 709,185 | 709,310 |
| GOLDEN STATE WATER COMPANY | Fair Value | ||
| Fair value of financial instruments | ||
| Long-term debt, fair value | $ 690,889 | $ 703,319 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset. No definition available.
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