Amount of Water Revenue Bonds Authorized to Finance Acquisition of the System in Claremont

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Represents the amount of environmental remediation costs paid by the third party.

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Represents the number of customers served by the entity.

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Total costs accrued as of the balance sheet date for environmental loss contingencies.

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The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities.

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Period end amount of total net PPE.

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Contingencies (Details) (GSWC, USD $)	12 Months Ended
Contingencies (Details) (GSWC, USD $)	Dec. 31, 2014 customer	Nov. 04, 2014
Environmental Clean-Up and Remediation
Contingencies
Amount spent in clean-up and remediation activities	4,500,000
Amount paid by the State of California Underground Storage Tank Fund for clean-up and remediation of plant facilities	1,500,000
Accrued liability for the estimated additional cost to complete the clean-up at the site	1,400,000
City of Claremont \| Condemnation of Properties
Contingencies
Amount of Water Revenue Bonds Authorized to Finance Acquisition of the System		135,000,000
Number of customers served through water systems	11,000
Ojai FLOW \| Condemnation of Properties
Contingencies
Number of customers served through water systems	3,000
City of Apple Valley [Member] \| Condemnation of Properties
Contingencies
Number of customers served through water systems	2,900
City of Artesia [Member] \| Condemnation of Properties
Contingencies
Number of customers served through water systems	3,300
Transmission and distribution \| City of Claremont \| Condemnation of Properties
Contingencies
Public Utilities, Property, Plant and Equipment, Net	47,700,000