CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2026	Mar. 31, 2025
Income Statement [Abstract]
Operating revenue	$ 183,293	$ 167,599
Production expenses:
Purchased water	26,945	25,953
Power	4,272	3,483
Groundwater extraction charges	23,209	18,291
Other production expenses	11,998	11,240
Total production expenses	66,424	58,967
Administrative and general	29,807	27,760
Maintenance	8,376	7,499
Property taxes and other non-income taxes	8,954	9,195
Depreciation and amortization	32,306	28,282
Total operating expense	145,867	131,703
Operating income	37,426	35,896
Other (expense) income:
Interest on long-term debt and other interest expense	(18,838)	(18,272)
Pension non-service credit	1,939	1,603
Other, net	1,879	795
Income before income taxes	22,406	20,022
Provision for income taxes	3,393	3,471
Net income (loss)	19,013	16,551
Other comprehensive loss, net	0	0
Comprehensive income	$ 19,013	$ 16,551
Earnings per share
Basic (in usd per share)	$ 0.50	$ 0.49
Diluted (in usd per share)	0.49	0.49
Dividends per share (in usd per share)	$ 0.44	$ 0.42
Weighted average shares outstanding
Basic (in shares)	37,931,742	33,778,792
Diluted (in shares)	38,549,353	33,868,565