CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($) $ in Thousands	Jun. 30, 2025	Dec. 31, 2024
Statement of Financial Position [Abstract]
Utility plant, at original cost (less accumulated depreciation - 2025 - $198,012; 2024 - $192,253)	$ 770,488	$ 747,186
Current assets
Cash and cash equivalents	349	1,147
Accounts and other receivables (less provision for expected credit loss - 2025 - $396; 2024 - $343)	11,002	11,339
Income tax receivable	112	624
Unbilled operating revenues	2,670	1,861
Materials and supplies	4,543	4,278
Prepaid property taxes	1	2,188
Prepaid expenses and other	3,622	3,091
Total current assets	22,299	24,528
Other assets
Non‑utility property (less accumulated depreciation - 2025 - $1,130; 2024 - $1,116)	3,581	3,603
Other deferred assets	6,986	6,525
Goodwill	1,939	1,939
Operating lease right-of-use assets	410	414
Total other assets	12,916	12,481
Regulatory assets, net	13,593	14,428
Total Assets	819,296	798,623
Stockholders' equity
Common stock	10,311	10,300
Preferred stock	0	0
Additional paid-in capital	144,173	143,920
Retained earnings	90,421	84,969
Total stockholders' equity	244,905	239,189
Long-term debt, net of current portion	175,138	176,509
Total stockholders' equity and long-term debt	420,043	415,698
Current liabilities
Lines of credit	1,986
Current portion of long-term debt	2,213	2,167
Accounts payable	10,424	11,228
Accrued expenses	3,109	5,336
Overdraft payable	62	31
Accrued interest	893	930
Income taxes payable	1,305	500
Customer and other deposits	3,387	3,347
Other	2,190	2,054
Total current liabilities	25,569	25,593
Commitments and contingencies
Deferred credits and other liabilities
Net advances for construction	1,453	1,582
Operating lease liabilities	401	404
Regulatory liabilities	29,664	30,267
Deferred investment tax credits	402	409
Deferred income taxes	52,730	52,265
Total deferred credits and other liabilities	84,650	84,927
Net contributions in aid of construction	289,034	272,405
Total Liabilities and Stockholders' Equity	$ 819,296	$ 798,623