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Contingencies (Details) - Environmental Clean-Up and Remediation - GOLDEN STATE WATER COMPANY $ in Millions | Mar. 31, 2025 USD ($) plantSite
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Loss Contingencies [Line Items] |
Number of plant facilities | plantSite | 1
Environmental costs recognized, capitalized | $ 6.8
Environmental loss contingencies paid by third party | 1.5
Accrued liability for the estimated additional cost to complete the clean-up at the site | $ 1.3

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