Condensed Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
OPERATING ACTIVITIES:
Net income	$ 16,394	$ 14,276
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	26,035	24,521
Deferred income taxes	8,732	11,421
Share-based compensation	451	513
Gain on sale of real estate investment	(910)	0
Loss on sale of utility property	0	23
Changes in operating assets and liabilities:
Accounts receivable and accrued unbilled utility revenue	(14,368)	(12,756)
Accounts payable, purchased power and other current liabilities	1,032	28
Accrued groundwater extraction charges and purchased water	4,274	4,559
Tax receivable and accrued taxes	6,899	4,809
Accrued interest	158	196
Accrued payroll	622	650
Other current asset	4,183	0
Postretirement benefits	3,853	2,421
Other changes, net	13	(1,644)
NET CASH PROVIDED BY OPERATING ACTIVITIES	57,368	49,017
INVESTING ACTIVITIES:
Company-funded	(67,731)	(43,346)
Contributions in aid of construction	(4,211)	(5,281)
Additions to real estate investments	(50)	(165)
Payments for business/asset acquisition and water rights	(1,971)	(2,065)
Cost to retire utility plant, net of salvage	(766)	(1,702)
Proceeds from sale of real estate investment	5,517	0
Proceeds from sale of utility property	0	43
NET CASH USED IN INVESTING ACTIVITIES	(69,212)	(52,516)
FINANCING ACTIVITIES:
Borrowings from line of credit	0	17,600
Repayments of line of credit	0	(16,100)
Long-term borrowings	0	50,000
Repayments of long-term borrowings	(3,497)	(925)
Debt issuance costs	(33)	(87)
Dividends paid	(9,920)	(9,616)
Exercise of stock options and similar instruments	731	547
Tax benefits realized from share options exercised	43	7
Receipts of advances and contributions in aid of construction	6,111	5,043
Refunds of advances for construction	(1,641)	(1,631)
NET CASH (USED IN) PROVIDED BY FINANCING ACTIVITIES	(8,206)	44,838
NET CHANGE IN CASH AND CASH EQUIVALENTS	(20,050)	41,339
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	26,734	1,730
CASH AND CASH EQUIVALENTS, END OF PERIOD	6,684	43,069
Cash paid (received) during the period for:
Interest	15,757	14,812
Income taxes	(3,406)	(5,269)
Supplemental disclosure of non-cash activities:
Increase in accrued payables for construction costs capitalized	9,815	1,518
Utility property installed by developers	$ 214	$ 0