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v3.24.2

Rate and Regulatory Matters (Details) - USD ($) $ in Thousands |  |  |  |  |  | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Sep. 30, 2024 | Jul. 01, 2024 | Jun. 30, 2024 | May 26, 2024 | Mar. 01, 2024 | Jun. 30, 2024 | Jun. 30, 2023 | Jun. 30, 2024 | Jun. 30, 2023 | Dec. 31, 2023 | Sep. 30, 2022 | Nov. 30, 2021
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  |  | $ 563,100 |  |  |  |  |  |
Return on equity |  |  |  |  |  | 9.60% |  |  |  |  |  |
Reclassification from regulatory liabilities |  |  | $ 171,315 |  |  | $ 171,315 |  | $ 171,315 |  | $ 226,725 |  |
Depreciation |  |  |  |  |  | 6,305 | $ 6,184 | 11,701 | $ 12,170 |  |  |
Carrying costs |  |  |  |  |  |  |  | 4,100 |  |  |  |
Previously incurred operating treatment costs |  |  | 1,400 |  |  | $ 1,400 |  | 1,400 |  |  |  |
Surcharge for costs incurred |  |  | 1,200 |  |  |  |  |  |  |  |  |
New Jersey Board of Public Utilities [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Reclassification from regulatory liabilities |  |  |  |  |  |  |  |  |  | $ 48,300 |  |
Depreciation |  |  |  |  |  |  |  | $ 900 |  |  |  |
Middlesex Water [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Escrow account |  |  |  |  |  |  |  |  |  |  | $ 1,700 |
Middlesex Water [Member] | New Jersey Board of Public Utilities [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  | $ 15,400 |  |  |  |  |  |  |
Maturity Less than 30 Days [Member] | Middlesex Water Company [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Escrow account |  |  |  |  |  |  |  |  |  |  |  | $ 1,700
Tidewater [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Operations and maintenance expense |  |  | $ 300 |  |  |  |  |  |  |  |  |
Series of Individually Immaterial Business Acquisitions [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Annual revenues |  |  |  | $ 500 |  |  |  |  |  |  |  |
Subsequent Event [Member] | Tidewater [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Revenue |  | $ 1,600 |  |  |  |  |  |  |  |  |  |
Forecast [Member] | Tidewater [Member] |  |  |  |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Operations and maintenance expense | $ 2,100 |  |  |  |  |  |  |  |  |  |  |

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