REVENUE RECOGNITION - Disaggregation of Revenues (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Disaggregation of Revenue [Abstract]
Revenues	$ 28,549	$ 27,416	$ 54,435	$ 51,960
Other Operating Revenue not in scope of ASC 606	624	428	1,065	775
Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	25,915	25,185	49,301	47,555
Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	2,010	1,803	4,069	3,630
Consumption Charges [Member] | Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	15,454	15,176	28,476	27,486
Fixed Fees [Member] | Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	9,335	9,102	18,600	18,422
Service Charges [Member] | Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	178	178	359	380
DSIC [Member] | Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	235	0	534	0
Metered Wastewater Services [Member] | Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	213	205	400	344
Industrial Wastewater Services [Member] | Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	500	524	932	923
Service Line Protection Plans [Member] | Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	1,614	1,424	3,245	2,854
Contract Operations [Member] | Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	249	238	501	505
Design and Installation [Member] | Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	3	5	7	59
Inspection Fees [Member] | Non-Tariff Revenue [Member]
Disaggregation of Revenue [Abstract]
Revenues	$ 144	$ 136	$ 316	$ 212