Regulatory Assets and Liabilities (Details) (USD $)	9 Months Ended
	Sep. 30, 2014	Aug. 14, 2014
2009 GRC pension plan cost
Balancing account disclosures
Regulatory asset	$ 3,000,000
Authorized amount of ratepayer refund	6,300,000
Conservation costs
Balancing account disclosures
Regulatory liabilities	4,900,000
2012 GRC pension plan cost
Balancing account disclosures
Regulatory liabilities	3,500,000
2012 GRC conservaion costs
Balancing account disclosures
Regulatory liabilities	2,000,000
Health care costs
Balancing account disclosures
Regulatory asset	1,900,000
Cal Water
Balancing account disclosures
Net regulatory receivable		30,600,000
Period over which ratepayer surcharges will be applied	3 years
Interim rate memorandum account balance	17,100,000
Regulatory asset	13,000,000
Deferred revenues	$ 500,000
Recovery from taxpayers (as a percent)	85.00%
Refund of excess to ratepayers (as a percent)	85.00%