SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES, Part 2 (Details) $ in Thousands		1 Months Ended			12 Months Ended
	Jul. 19, 2022 USD ($) Installment	Jul. 31, 2023 USD ($)	Aug. 31, 2022 USD ($)	Jan. 31, 2017	Dec. 31, 2023 USD ($) Installment Refund	Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017	Jan. 31, 2019 USD ($)
Amortization period of other regulatory expense [Abstract]
Deferred contract costs and other					5 years
Rate case studies					5 years
Deferred costs affiliated interest agreement					20 years
Goodwill					50 years
Deferred acquisition costs					20 years
Franchise costs					80 years
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					$ 7,289	$ 7,274
Impairment or Disposal of Long-Lived Assets [Abstract]
Impairment					0	0	$ 0
Goodwill [Abstract]
Goodwill					1,939	1,939
Summary of other deferred assets net of amortization [Abstract]
Investment in Co Bank					5,882	5,351
Settlement agreement receivable-long term					2,496	4,991
Other deferred assets					126	194
Other deferred assets					8,504	10,536
Contributions in Aid of Construction [Abstract]
Refund for contributions in aid of construction due to tax status change						$ 3,600
Regulatory Liabilities [Line Items]
Litigation settlement amount	$ 10,000				10,000
Litigation settlement amount received		$ 2,500	$ 2,500
Litigation settlement, remaining amount					$ 5,000
Number of installments | Installment	2				2
Number of refunds | Refund					2
Federal corporate tax rate					21.00%	21.00%	21.00%		34.00%
Decrease in the net deferred income tax liability								$ (24,300)
Net regulatory liability amount								$ 22,800
Regulatory Liabilities					$ 25,676	$ 28,721
Minimum [Member]
Amortization period of other regulatory expense [Abstract]
Amortization period of debt related cost				15 years
Maximum [Member]
Amortization period of other regulatory expense [Abstract]
Amortization period of debt related cost				30 years
Maryland [Member]
Amortization period of other regulatory expense [Abstract]
Rate proceedings					5 years
Delaware [Member]
Amortization period of other regulatory expense [Abstract]
Rate proceedings					3 years
DEPSC [Member]
Regulatory Liabilities [Line Items]
Net regulatory liability amount										$ 22,200
Regulatory liabilities, amortization period					49 years 6 months
MDPSC [Member]
Regulatory Liabilities [Line Items]
Net regulatory liability amount					$ 600
Artesian Water [Member]
Contributions in Aid of Construction [Abstract]
Amount received in grant					3,800	2,000
Deferred Settlement Refunds [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities					5,000	7,500
Deferred Income Taxes [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities					20,700	21,200
Deferred Contract Costs and Other [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					209	227
Rate Case Studies [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					136	57
Rate Proceedings [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					385	0
Deferred Income Taxes [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					444	465
Debt Related Costs [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					4,322	4,682
Deferred Costs Affiliated Interest Agreement [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					1,110	1,114
Goodwill [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					258	266
Deferred Acquisition and Franchise Costs [Member]
Regulatory assets net of amortization, comprise [Abstract]
Regulatory assets, net					$ 425	$ 463