Rate and Regulatory Matters (Details) - USD ($) $ in Millions		1 Months Ended			9 Months Ended
	Apr. 12, 2023	Oct. 31, 2023	Sep. 30, 2022	May 31, 2021	Sep. 30, 2023	Nov. 30, 2021
Minimum [Member]
Rate and Regulatory Matters [Line Items]
Deferred Income, Revenue Recognized					$ 46.0
Maximum [Member]
Rate and Regulatory Matters [Line Items]
Deferred Income, Revenue Recognized					$ 77.0
Middlesex Water [Member]
Rate and Regulatory Matters [Line Items]
Escrow account			$ 1.7
Maturity Less than 30 Days [Member] | Middlesex Water Company [Member]
Rate and Regulatory Matters [Line Items]
Escrow account						$ 1.7
New Jersey Board of Public Utilities [Member] | Middlesex Water [Member]
Rate and Regulatory Matters [Line Items]
Approved increase in annual operating revenues			$ 2.7	$ 34.0
New Jersey Board of Public Utilities [Member] | Pinelands [Member]
Rate and Regulatory Matters [Line Items]
Approved increase in annual operating revenues	$ 1.0
Subsequent Event [Member] | New Jersey Board of Public Utilities [Member] | Middlesex Water [Member]
Rate and Regulatory Matters [Line Items]
Approved increase in annual operating revenues		$ 2.7