Amount of drawn expected remaining.

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Advances from customers for construction.

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No definition available.

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- Definition

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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No definition available.

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

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No definition available.

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Percentage of offering shares on discount to participants.

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No definition available.

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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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No definition available.

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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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No definition available.

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- Definition

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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The cash inflow from a debt initially having maturity due after one year or beyond the operating cycle, if longer.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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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
	Aug. 31, 2019	Mar. 31, 2020	Mar. 31, 2019	Feb. 28, 2020	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		47,649	4,834
Issuance of shares under the DRP		$ 313	$ 2,559
Common stock granted and issued under plan	200,000
Percentage of offering shares on discount to participants	5.00%
Other long term debt		87,600			$ 83,000
Customer advances		24,146			$ 23,905
Amount drawn		5,398	$ 6,899
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		$ 1,500				$ 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%
New Jersey Infrastructure Bank [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan									$ 43,500
Interest rate		0.00%
Percentage of principal with stated interest rate		75.00%
Percentage of principal with market interest rate		25.00%
Middlesex [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan		$ 37,000
First Mortgage Bonds [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing capacity, construction loan	$ 53,700	60,800
Amount drawn		23,400
Proceeds from issuance premium	$ 7,100
Amount of drawn expected remaining		$ 37,400
New Jersey Board Of Public Utilities [Member] \| Middlesex [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing amount				$ 100,000