Amount of drawn expected remaining.

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Advances from customers for construction.

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The maximum borrowing capacity for the construction loan as outlined in the closed agreement. Borrowings will take place when construction on a qualifying project is substantially complete.

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The maximum borrowing amount for other loan sources not specifically stated in the taxonomy.

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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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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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Number of shares issued during the period from a dividend reinvestment plan (DRIP). A dividend reinvestment plan allows the shareholders 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		6 Months Ended
	Aug. 31, 2019	Jan. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 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						129,675
Issuance of shares under the DRP			$ 294	$ 4,522	$ 608	$ 7,081
Common stock granted and issued under plan		200,000
Percentage of offering shares on discount to participants		5.00%
Other long term debt			91,000		91,000		$ 83,000
Customer advances			24,342		24,342		$ 23,905
Amount drawn					9,721	$ 13,217
Middlesex [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan			413		413
Proceeds from private placement					40
Middlesex [Member] \| New Jersey Board Of Public Utilities [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing amount			$ 1,000		$ 1,000
New Jersey Infrastructure Bank [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan											$ 435
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	$ 71
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	$ 537		$ 608		$ 608
Amount drawn					323
Amount of drawn expected remaining					$ 285