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Rate and Regulatory Matters (Details) - USD ($) |  |  |  |  |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 02, 2023 | Dec. 31, 2022 | Aug. 31, 2022 | Jan. 02, 2022 | Mar. 31, 2021 | Sep. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2021 | Nov. 30, 2021
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Corporate tax rate |  |  | 6.00% |  |  |  |  |  |
Annual revenues |  |  |  |  |  |  | $ 2,200,000 |  |
DSIC rate, description |  |  |  |  |  |  | Tidewater reset its Distribution System Improvement Charge (DSIC) rate to zero effective April 1, 2021 |  |
capital expenditures rate |  |  |  |  |  |  | 5.39% |  |
Regulatory liabilities |  | $ 290,000,000 |  |  |  |  | $ 290,000,000 | $ 30,400,000 |
Maximum [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Corporate tax rate |  |  |  |  |  |  | 35.00% |  |
Minimum [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Corporate tax rate |  |  |  |  |  |  | 21.00% |  |
Delaware Public Service Commission [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Percentage of consumer price index |  |  |  |  |  |  | 3.00% |  |
Maturity date |  |  |  |  |  |  | Dec. 31, 2029 |  |
Middlesex Water [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Regulatory liabilities |  | 17,700,000 |  |  |  |  | $ 17,700,000 | 16,100,000 |
Middlesex Water [Member] | New Jersey Board of Public Utilities [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues |  | 2,700,000 |  | $ 20,700,000 | $ 1,100,000 |  |  | 27,700,000 |
Base rate amount |  |  |  |  |  |  |  | $ 513,500,000 |
Return on equity |  |  |  |  |  |  |  | 9.60% |
Regulatory liabilities |  | $ 0 |  |  |  |  | $ 0 | $ 3,000,000 |
Tidewater [Member] | Delaware Public Service Commission [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  | $ 1 |  |  |  |
Pinelands [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  |  | $ 400,000 |  |  |
Pinelands [Member] | New Jersey Board of Public Utilities [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  |  | $ 600,000 |  |  |
Middlesex Water Company [Member] | Maturity Less than 30 Days [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Escrow account |  |  |  |  |  |  |  |  | $ 1,700,000
Forecast [Member] | Middlesex Water [Member] | New Jersey Board of Public Utilities [Member] |  |  |  |  |  |  |  |  |
Rate and Regulatory Matters (Details) [Line Items] |  |  |  |  |  |  |  |  |
Approved increase in annual operating revenues | $ 7,000,000 |  |  |  |  |  |  |  |

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