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Capitalization (Narrative) (Details) - USD ($) $ in Thousands	1 Months Ended	9 Months Ended
	Nov. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Aug. 31, 2017	May 31, 2017	Jan. 31, 2017	Dec. 31, 2016
Schedule of Capitalization [Line Items]
Issuance of shares under the DRP, shares		24,154	35,350
Issuance of shares under the DRP		$ 900	$ 1,200
Other long term debt		64,100					$ 59,700
Customer advances		$ 21,307					$ 20,846
Series XX [Member] | Subsequent Event [Member]
Schedule of Capitalization [Line Items]
Proceeds from issuance of first mortgage bond	$ 11,100
Interest rate	0.00%
Due date of debt	Aug. 01, 2047
Series YY [Member] | Subsequent Event [Member]
Schedule of Capitalization [Line Items]
Proceeds from issuance of first mortgage bond	$ 3,700
Due date of debt	Aug. 01, 2047
New Jersey SRF Program [Member]
Schedule of Capitalization [Line Items]
Maximum borrowing amount						$ 37,000
Maximum borrowing capacity, construction loan				$ 9,500	$ 2,300

X

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

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- Definition

For utilities only, represents the carrying amount of the liability as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.

+ References

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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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- Definition

Amount of long-term debt classified as other.

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The cash inflow from amounts received from a long-term debt instrument secured by a first mortgage deed of trust, containing a pledge of real property. The lender has the highest claim on the property in case of default.

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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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