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Commitments and Contingent Liabilities (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) gal	Sep. 30, 2021 USD ($)
Purchase Commitment, Excluding Long-Term Commitment [Line Items]
Construction program | $			$ 85.0
Estimated obligation expenditure | $			26.0
Rental expenses under operating leases | $	$ 0.2	$ 0.2	$ 0.6	$ 0.6
Estimated incremental borrowing rate	(4.03%)		(4.03%)
NJ Water Supply Authority [Member]
Purchase Commitment, Excluding Long-Term Commitment [Line Items]
Purchase commitment expiration date of contract			Nov. 30, 2023
Water purchase per commitment | gal			27
Regulated Water Authority [Member]
Purchase Commitment, Excluding Long-Term Commitment [Line Items]
Purchase commitment expiration date of contract			Feb. 27, 2026
Water purchase per commitment | gal			3
City of Dover [Member]
Purchase Commitment, Excluding Long-Term Commitment [Line Items]
Water purchase per commitment | gal			15

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- Definition

Budgeted construction cost for construction program, next year.

+ References

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- Definition

Estimated incremental borrowing rate.

+ References

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- Definition

Estimated obligation expenditure.

+ References

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- Definition

The expiration date of a long-term purchase commitment.

+ References

No definition available.

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- Definition

Number of units of goods that must be purchased within the specified time period of the agreement to avoid penalties or unfavorable effects on pricing, among other adverse consequences.

+ References

No definition available.

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X

- Definition

Amount of operating lease income from lease payments paid and payable to lessor. Excludes variable lease payments not included in measurement of lease receivable.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 270
-SubTopic 10
-Section 50
-Paragraph 6A
-URI https://asc.fasb.org/extlink&oid=126900988&loc=SL77927221-108306

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 30
-Section 50
-Paragraph 5
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=124258985&loc=SL77919372-209981

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- Definition

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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