v3.26.1
Segment Reporting - Reportable Segment and Other Business Activities (Details) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2026
Mar. 31, 2026
Jun. 30, 2025
Mar. 31, 2025
Jun. 30, 2026
Jun. 30, 2025
Dec. 31, 2025
Segment Reporting [Line Items]              
Operating revenue $ 210,474   $ 198,255   $ 393,767 $ 365,854  
Less:              
Production expenses 85,481   80,869   151,905 139,836  
Administrative and general 33,626   28,795   63,433 56,555  
Maintenance 7,455   7,470   15,831 14,969  
Property taxes and other non-income taxes 9,024   8,506   17,978 17,701  
Depreciation and amortization 32,134   28,750   64,440 57,032  
Interest on long-term debt and other interest expense 17,952   18,122   36,790 36,394  
Provision (benefit) for income taxes 3,978   4,670   7,371 8,141  
Other (5,765)   (3,602)   (9,583) (6,000)  
Net income 26,589 $ 19,013 24,675 $ 16,551 45,602 41,226  
Capital expenditures 121,936   132,058   214,444 216,403  
Assets 5,437,264       5,437,264   $ 5,149,566
Operating Segments | Water Utility Services              
Segment Reporting [Line Items]              
Operating revenue 206,715   194,674   386,104 359,830  
Less:              
Production expenses 83,981   79,324   149,407 137,309  
Administrative and general 27,396   24,967   55,657 51,718  
Maintenance 6,740   6,745   13,619 13,748  
Property taxes and other non-income taxes 9,055   8,506   17,961 17,715  
Depreciation and amortization 31,872   28,485   63,916 56,517  
Interest on long-term debt and other interest expense 13,496   12,719   27,997 25,758  
Provision (benefit) for income taxes 5,971   6,706   11,871 12,012  
Other (4,457)   (1,748)   (8,022) (2,870)  
Net income 32,661   28,970   53,698 47,923  
Capital expenditures 121,936   132,058   214,444 216,403  
Assets 5,270,343       5,270,343   5,054,235
Other Services              
Segment Reporting [Line Items]              
Operating revenue 3,759   3,581   7,663 6,024  
Less:              
Production expenses 1,500   1,545   2,498 2,527  
Administrative and general 201   252   418 812  
Maintenance 715   725   2,212 1,221  
Property taxes and other non-income taxes 35   9   78 (50)  
Depreciation and amortization 30   34   60 61  
Interest on long-term debt and other interest expense 69   0   69 0  
Provision (benefit) for income taxes 370   283   731 509  
Other (58)   (38)   (151) (137)  
Net income 897   771   1,748 1,081  
Capital expenditures 0   0   0 0  
Assets 22,953       22,953   26,707
Unallocated Corporate              
Segment Reporting [Line Items]              
Operating revenue 0   0   0 0  
Less:              
Production expenses 0   0   0 0  
Administrative and general 6,029   3,576   7,358 4,025  
Maintenance 0   0   0 0  
Property taxes and other non-income taxes (66)   (9)   (61) 36  
Depreciation and amortization 232   231   464 454  
Interest on long-term debt and other interest expense 4,387   5,403   8,724 10,636  
Provision (benefit) for income taxes (2,363)   (2,319)   (5,231) (4,380)  
Other (1,250)   (1,816)   (1,410) (2,993)  
Net income (6,969)   (5,066)   (9,844) (7,778)  
Capital expenditures 0   $ 0   0 $ 0  
Assets $ 143,968       $ 143,968   $ 68,624