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Rate and Regulatory Matters - Schedule of Regulatory Assets and Liabilities (Details) - USD ($) $ in Thousands | Dec. 31, 2024 | Dec. 31, 2023
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Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |
Regulatory Assets |  | $ 101,783 | $ 90,694
Regulatory Liabilities |  |  |
Regulatory Liabilities |  | 64,557 | 113,021
Income Taxes [Member] |  |  |
Regulatory Liabilities |  |  |
Regulatory Liabilities | [1] | 27,380 | 28,188
Cost of Removal [Member] |  |  |
Regulatory Liabilities |  |  |
Regulatory Liabilities | [2] | 20,595 | 19,727
Employee Benefit Plans [Member] |  |  |
Regulatory Liabilities |  |  |
Regulatory Liabilities | [3] | 9,435 | 1,471
Lawsuit Settlement [Member] |  |  |
Regulatory Liabilities |  |  |
Regulatory Liabilities | [4] | 5,334 | 63,635
New Jersey Revenue Taxes [Member] |  |  |
Regulatory Liabilities |  |  |
Regulatory Liabilities | [5] | 1,813 |
Income Taxes [Member] |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |
Regulatory Assets | [6] | 89,825 | 84,419
Other Regulatory Assets [Member] |  |  |
Schedule of Regulatory Assets and Liabilities [Line Items] |  |  |
Regulatory Assets | [7] | $ 11,958 | $ 6,275
[1] | The 2017 Tax Act reduced the statutory corporate federal income tax rate from 35% to 21%. The tariff rates charged to customers effective prior to 2018 in the Company’s regulated companies include recovery of income taxes at the statutory rate in effect at the time those rates were approved by the respective state public utility commissions. The Company has recorded regulatory liabilities for excess income taxes collected through rates due to the lower income tax rate under the 2017 Tax Act. These regulatory liabilities are overwhelmingly related to utility plant depreciation deduction timing differences, which are subject to Internal Revenue Service (IRS) normalization rules. The IRS rules limit how quickly the excess taxes attributable to accelerated taxes can be returned to customers. The current base rates for Middlesex and Pinelands customers became effective after 2017 and reflect the impact of the 2017 Tax Act.
[2] | The Company uses composite depreciation rates for its regulated utility assets, which is currently an acceptable method under GAAP and is widely used in the utility industry. Historically, under the composite depreciation method, the anticipated costs of removing assets upon retirement are provided for over the life of those assets as a component of depreciation expense. The Company recovers certain asset retirement costs through rates charged to customers as an approved component of depreciation expense.
[3] | Retirement benefits include pension and other retirement benefits that have been recorded on the Consolidated Balance Sheet in accordance with the guidance provided in ASC 715, Compensation – Retirement Benefits. These amounts represent obligations less than current funding.
[4] | The net proceeds available to Middlesex from the 3M Settlement Agreement were recorded as a regulatory liability and are being used for future related operating and maintenance costs.
[5] | Revenue related taxes paid by the Company's New Jersey Regulated subsidiaries, and reflected in those subsidiaries current base rates, were above enacted rates and will be refunded back to customers in a future rate proceeding.
[6] | The recovery period for income taxes is dependent upon when the temporary differences between the tax and book treatment of various items reverse.
[7] | Other primarily includes deferred costs for rate cases and tank painting.

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