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Contingencies (Details) $ in Millions | 3 Months Ended
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Mar. 31, 2021 USD ($)
Loss Contingencies [Line Items] |
Amount spent in clean-up and remediation activities [Abstract] | $ 1.5
Term estimate for the environmental cleanup | 2 years
Environmental Clean-Up and Remediation | GOLDEN STATE WATER COMPANY |
Loss Contingencies [Line Items] |
Environmental Remediation Expense | $ 6.4
Accrued liability for the estimated additional cost to complete the clean-up at the site | $ 1.3

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