Sale of California Water Service (Details) (USD $) In Thousands, except Share data, unless otherwise specified	0 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Investments, Debt and Equity Securities [Abstract]
Available for Sale Marketable Security, Shares Sold	125,969
Available-for-sale Securities, Gross Realized Gains (Losses), Sale Proceeds	$ 3,056
Fees Incurred on Sale of Available for Sale Securities	10
Gain on sale of California Water Service Group stock	2,017	2,017	0	2,017	0
Available-for-sale Securities, Income Tax Expense on Realized Gain (Loss)	822
Gain (Loss) on Sale of Securities, Net	1,195
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, Net of Tax	$ 1,171	$ 1,171	$ 0	$ 1,171	$ 0
Available For Sale Securities, Number of Securities Held		259,151		259,151