Condensed Consolidating Financial Statements (Details 3) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Condensed Consolidating Financial Statements
Operating revenue	$ 158,416	$ 154,555	$ 268,931	$ 265,999
Operations:
Water production costs	61,915	59,645	107,317	101,342
Administrative and general	23,796	23,155	48,937	48,436
Other	16,004	17,030	32,380	32,675
Maintenance	4,988	4,188	9,993	8,321
Depreciation and amortization	16,087	14,491	32,140	29,120
Income tax expense (benefit)	7,190	9,548	3,351	8,402
Taxes other than income taxes	5,144	5,715	10,369	11,150
Total operating expenses	135,124	133,772	244,487	239,446
Net operating income	23,292	20,783	24,444	26,553
Other Income and Expenses:
Non-regulated revenue	3,474	3,215	7,754	6,737
Non-regulated expenses, net	(2,253)	(3,240)	(6,372)	(5,657)
Income tax (expense) on other income and expense	(481)	16	(560)	(435)
Net other income (loss)	740	(9)	822	645
Interest:
Interest expense	7,077	7,803	14,152	15,840
Less: capitalized interest	(215)	(539)	(580)	(1,079)
Net interest expense	6,862	7,264	13,572	14,761
Net Income	17,170	13,510	11,694	12,437
Consolidating Adjustments
Operations:
Other	(126)	(125)	(252)	(252)
Depreciation and amortization	(26)	(28)	(53)	(56)
Income tax expense (benefit)	237	370	454	716
Total operating expenses	85	217	149	408
Net operating income	(85)	(217)	(149)	(408)
Other Income and Expenses:
Non-regulated revenue	(554)	(795)	(1,147)	(1,557)
Income tax (expense) on other income and expense	226	359	432	693
Net other income (loss)	(328)	(436)	(715)	(864)
Interest:
Interest expense	(429)	(669)	(896)	(1,305)
Net interest expense	(429)	(669)	(896)	(1,305)
Equity earnings of subsidiaries	(16,985)	(13,291)	(11,304)	(12,078)
Net Income	(16,969)	(13,275)	(11,272)	(12,045)
Parent Company
Operations:
Administrative and general	33		33
Depreciation and amortization	57	28	100	28
Income tax expense (benefit)	(55)	(93)	(105)	(229)
Total operating expenses	35	(65)	28	(201)
Net operating income	(35)	65	(28)	201
Other Income and Expenses:
Non-regulated revenue	450	597	917	1,167
Income tax (expense) on other income and expense	(184)	(244)	(374)	(476)
Net other income (loss)	266	353	543	691
Interest:
Interest expense	46	199	125	533
Net interest expense	46	199	125	533
Equity earnings of subsidiaries	16,985	13,291	11,304	12,078
Net Income	17,170	13,510	11,694	12,437
Cal Water
Condensed Consolidating Financial Statements
Operating revenue	150,340	146,730	254,089	251,161
Operations:
Water production costs	59,514	57,102	102,882	96,543
Administrative and general	21,090	20,460	43,862	43,069
Other	14,363	15,418	29,025	29,607
Maintenance	4,833	4,029	9,656	7,994
Depreciation and amortization	14,961	13,697	29,915	27,454
Income tax expense (benefit)	7,429	9,813	4,081	9,086
Taxes other than income taxes	4,493	5,015	9,143	9,869
Total operating expenses	126,683	125,534	228,564	223,622
Net operating income	23,657	21,196	25,525	27,539
Other Income and Expenses:
Non-regulated revenue	3,208	3,005	7,237	6,187
Non-regulated expenses, net	(2,109)	(2,873)	(5,748)	(4,793)
Income tax (expense) on other income and expense	(447)	(54)	(606)	(568)
Net other income (loss)	652	78	883	826
Interest:
Interest expense	6,984	7,631	13,944	15,358
Less: capitalized interest	(197)	(405)	(538)	(784)
Net interest expense	6,787	7,226	13,406	14,574
Net Income	17,522	14,048	13,002	13,791
All Other Subsidiaries
Condensed Consolidating Financial Statements
Operating revenue	8,076	7,825	14,842	14,838
Operations:
Water production costs	2,401	2,543	4,435	4,799
Administrative and general	2,673	2,695	5,042	5,367
Other	1,767	1,737	3,607	3,320
Maintenance	155	159	337	327
Depreciation and amortization	1,095	794	2,178	1,694
Income tax expense (benefit)	(421)	(542)	(1,079)	(1,171)
Taxes other than income taxes	651	700	1,226	1,281
Total operating expenses	8,321	8,086	15,746	15,617
Net operating income	(245)	(261)	(904)	(779)
Other Income and Expenses:
Non-regulated revenue	370	408	747	940
Non-regulated expenses, net	(144)	(367)	(624)	(864)
Income tax (expense) on other income and expense	(76)	(45)	(12)	(84)
Net other income (loss)	150	(4)	111	(8)
Interest:
Interest expense	476	642	979	1,254
Less: capitalized interest	(18)	(134)	(42)	(295)
Net interest expense	458	508	937	959
Net Income	$ (553)	$ (773)	$ (1,730)	$ (1,746)