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Advances from customers for construction.

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Percentage of offering shares on discount to participants.

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The percentage of the loan balance that is subject to the market interest rate at the time of closing in the contractual debt agreement.

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The percentage of the loan balance that is subject to the stated interest rate in the contractual debt agreement.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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Amount of long-term debt classified as other.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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Value of stock issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the holder of the stock to reinvest dividends paid to them by the entity on new issues of stock by the entity.

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Capitalization (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended		3 Months Ended		9 Months Ended
	Aug. 31, 2019	Jan. 31, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019	Apr. 30, 2019	Dec. 31, 2018	Sep. 30, 2018	Aug. 31, 2018	May 31, 2018	Mar. 31, 2018
Schedule of Capitalization [Line Items]
Issuance of shares under the DRP, shares					14,223	221,558
Issuance of shares under the DRP			$ 313	$ 5,368	$ 921	$ 12,449
Common stock granted and issued under plan		200,000
Percentage of offering shares on discount to participants		5.00%
Other long term debt			90,900		90,900		$ 83,000
Customer advances			25,100		25,100		$ 23,905
Amount drawn					10,319	$ 82,446
Middlesex [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan			41,900		41,900
Proceeds from private placement					40,000
Middlesex [Member] \| New Jersey Board Of Public Utilities [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing amount			$ 100,000		$ 100,000
FMB [Member]
Schedule of Capitalization [Line Items]
Percentage of principal with stated interest rate					2.90%
Debt Instrument Maturity Date					Nov. 30, 2050
New Jersey Infrastructure Bank [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan											$ 43,500
Interest rate			0.00%		0.00%
Percentage of principal with stated interest rate					75.00%
Percentage of principal with market interest rate					25.00%
First Mortgage Bonds [Member]
Schedule of Capitalization [Line Items]
Proceeds from issuance premium	$ 7,100
New Jersey NJIB Program [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan										$ 8,700
Delaware State Revolving Fund [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing amount									$ 10,000				$ 900
Maximum borrowing capacity, construction loan								$ 1,700
Series 2018A [Member]
Schedule of Capitalization [Line Items]
Interest rate												0.00%
Series 2019A [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan	$ 32,500
Interest rate	4.00%
Series 2019B [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan	$ 21,200
Interest rate	5.00%
First Mortgage Bonds [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan	$ 53,700		$ 60,800		$ 60,800
Amount drawn					38,100
Amount of drawn expected remaining					$ 22,700