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-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
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-Name Accounting Standards Codification
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-SubTopic 10
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-URI http://asc.fasb.org/extlink&oid=118943535&loc=d3e11049-110243

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

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- Definition

The minimum amount the entity agreed to spend under the 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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- 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.

+ References

No definition available.

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Commitments and Contingent Liabilities (Narrative) (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2019 USD ($) gal	Mar. 31, 2018 USD ($)	Dec. 31, 2018 USD ($)
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Guaranty liabilty for AWM's performance	$ 1,500		$ 1,500
Budgeted construction cost for construction program, 2018	112,000
Contractual construction agreements	17,000
Rental expenses under operating leases	$ 100	$ 100
Estimated incremental borrowing rate	4.03%
Lease maturity date		2030
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	27,000,000
Regulated Water Authority [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Purchase commitment expiration date of contract	Feb. 27, 2021
Water purchase per commitment \| gal	3,000,000
City of Dover [Member]
Purchase Commitment, Excluding Long-term Commitment [Line Items]
Water purchase per commitment \| gal	15,000,000