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Rate and Regulatory Matters (Details) - USD ($) $ in Millions				1 Months Ended	12 Months Ended
	Apr. 12, 2023	Jan. 02, 2023	Jan. 02, 2022	Sep. 30, 2022	Dec. 31, 2021	Nov. 30, 2021
Middlesex Water [Member]
Rate and Regulatory Matters (Details) [Line Items]
Escrow account				$ 1.7
Maturity Less than 30 Days [Member] | Middlesex Water Company [Member]
Rate and Regulatory Matters (Details) [Line Items]
Escrow account						$ 1.7
New Jersey Board of Public Utilities [Member] | Middlesex Water [Member]
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues		$ 7.0	$ 20.7	$ 2.7	$ 27.7
Subsequent Event [Member] | New Jersey Board of Public Utilities [Member] | Pinelands [Member]
Rate and Regulatory Matters (Details) [Line Items]
Approved increase in annual operating revenues	$ 1.0

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- References

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The designation of funds furnished by a borrower to a lender to assure future payments of the borrower's real estate taxes and insurance obligations with respect to a mortgaged property. Escrow deposits may be made for a variety of other purposes such as earnest money and contingent payments. This element excludes replacement reserves which are an escrow separately provided for within the US GAAP taxonomy.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 954
-SubTopic 440
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (d)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147480327/954-440-50-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03.10)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147479853/942-210-S99-1

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- Definition

Amount of public utility's approved rate increase (decrease) by regulatory agency.

+ References

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