CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
Operating activities:
Net income	$ 102,578	$ 93,967	$ 84,987
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	120,490	115,050	108,138
Deferred income taxes	5,183	10,355	(8,510)
Stock-based compensation	6,444	5,623	4,647
Allowance for equity funds used during construction	(6,237)	(2,362)	(2,114)
Loss on sale of nonutility properties and other assets	0	572	0
Changes in operating assets and liabilities, net of acquired assets and liabilities:
Accounts receivable and accrued unbilled revenue	(3,234)	(12,663)	(10,869)
Accounts payable and other current liabilities	9,280	4,241	492
Accrued groundwater extraction charges, purchased water and power	4,204	639	4,772
Tax receivable and payable, and other accrued taxes	(18,280)	(18,355)	(22,415)
Postretirement benefits	(5,682)	(4,400)	(1,549)
Regulatory assets and liabilities excluding income tax temporary differences and postretirement benefits	7,374	(1,812)	12,278
Up-front service concession payments	0	(23,900)	0
Other noncurrent assets and liabilities	26,114	21,042	20,756
Proceeds from litigation settlement, net	7,823	0	0
Other changes, net	(11,254)	7,529	218
Net cash provided by operating activities	244,803	195,526	190,831
Investing activities:
Company-funded	(489,607)	(353,029)	(271,772)
Contributions in aid of construction	(30,146)	(24,179)	(16,855)
Additions to nonutility assets and real estate investments	0	(29)	(24,244)
Payments for business acquisitions	0	0	(7,537)
Cost to retire utility plant, net of salvage	(3,149)	(3,430)	(2,097)
Proceeds from sale of real estate investments and release of escrow deposit	2,801	40,572	233
Net cash used in investing activities	(520,101)	(340,095)	(322,272)
Financing activities:
Borrowings from lines of credit	436,530	242,000	146,415
Repayments of lines of credit	(468,821)	(295,260)	(134,493)
Long-term borrowings	185,167	185,329	70,000
Repayments of long-term borrowings	(3,861)	(48,975)	(4,347)
Dividends paid	(58,645)	(52,132)	(47,905)
Receipts of advances and contributions in aid of construction	59,902	33,070	22,425
Refunds of advances for construction	(4,404)	(2,963)	(2,763)
Issuance of common stock, net of issuance costs	122,808	85,008	80,659
Proceeds from litigation settlement, net	16,949	0	0
Other changes, net	(755)	(117)	(1,171)
Net cash provided by financing activities	284,870	145,960	128,820
Net change in cash and cash equivalents	9,572	1,391	(2,621)
Cash and cash equivalents, beginning of year	11,114	9,723	12,344
Cash and cash equivalents, end of year	20,686	11,114	9,723
Cash paid (refunded) during the year for:
Interest	79,428	73,268	67,508
Interest, net of amounts capitalized	72,093	69,744	64,608
Income taxes	3,238	(598)	23,020
Supplemental disclosure of non-cash activities:
Accrued payables for additions to utility plant	48,146	41,692	35,904
Utility property installed by developers	3,686	2,465	3,341
Proceeds receivable from sale of real estate investments	0	2,801	0
Accrued selling expenses on sale of real estate investments	0	2,177	0
Seller financing in asset acquisition, net of discount	$ 0	$ 0	$ 15,400