Contingencies (Details) $ in Millions	6 Months Ended
	Jun. 30, 2020 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	$ 6.3
Accrued liability for the estimated additional cost to complete the clean-up at the site	$ 1.3