Consolidated Statements of Income and Comprehensive Income (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Operating revenue	$ 238,955	$ 215,638	$ 216,097
Operating expense:
Purchased water	54,317	43,557	45,317
Power	5,394	6,429	6,582
Groundwater extraction charges	20,997	26,614	31,635
Other production costs	11,345	10,702	10,074
Total production costs	92,053	87,302	93,608
Administrative and general	39,136	38,184	35,445
Maintenance	13,261	12,242	13,172
Property taxes and other non-income taxes	8,921	7,907	8,549
Depreciation and amortization	31,193	28,331	25,643
Impairment on real estate investment	0	3,597	0
Total operating expense	184,564	177,563	176,417
Operating income	54,391	38,075	39,680
Other (expense) income:
Interest on long-term debt	(17,799)	(15,676)	(13,996)
Mortgage and other interest expense	(1,876)	(2,007)	(1,974)
Loss on sale of utility property	(23)	0	0
Gain on sale of California Water Service Group stock	0	18,966	0
Dividend income	238	1,185	1,298
Other, net	513	603	443
Income before income taxes	35,444	41,146	25,451
Provision for income taxes	14,566	16,740	10,280
Net income	20,878	24,406	15,171
Other comprehensive loss:
Unrealized loss on investment, net of taxes of $59 in 2011, $30 in 2010 and $4,334 in 2009	(85)	(44)	(6,236)
Reclassification adjustment for gain realized on investment, net of tax of $7,494 in 2010	0	(10,784)	0
Comprehensive income	$ 20,793	$ 13,578	$ 8,935
Earnings per share
Basic	$ 1.12	$ 1.32	$ 0.82
Diluted	$ 1.11	$ 1.30	$ 0.81
Weighted average shares outstanding
Basic	18,581,762	18,531,458	18,486,536
Diluted	18,794,066	18,742,315	18,680,458