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v3.19.3.a.u2

Rate and Regulatory Matters (Narrative) (Details) $ in Thousands |  | 1 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 01, 2019 | Nov. 30, 2019 USD ($) Customer | Oct. 31, 2019 USD ($) | Mar. 31, 2018 USD ($) | Dec. 31, 2019 USD ($) | Dec. 31, 2018 USD ($) | Dec. 31, 2017 USD ($)
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Regulatory Liability - Cost of Utility Plant Removal |  |  |  |  | $ 69,152 | $ 79,112 |
Corporate tax rate | 3.35% |  |  |  |  |  |
Regulatory liabilities |  |  |  |  | 31,500 | 31,700 |
Deferred income tax benefits |  |  |  |  | $ (11,719) | (8,724) | $ 7,944
Maximum [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Corporate tax rate |  |  |  |  | 35.00% |  |
Minimum [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Corporate tax rate |  |  |  |  | 21.00% |  |
Pinelands Water Company [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  | $ 500 |  |  |  |
Pinelands Wastewater [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  | $ 500 |  |  |  |
Delaware Public Service Commission [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Percentage of consumer price index |  |  |  |  | 3.00% |  |
Maturity date |  |  |  |  | Dec. 31, 2029 |  |
Delaware Public Service Commission [Member] | Tidewater [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  | $ 500 |  |
Number of customers | Customer |  | 1,000 |  |  |  |  |
Purchase of the wastewater utility assets |  | $ 1,800 |  |  |  |  |
New Jersey Board Of Public Utilities [Member] | Middlesex [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  | $ 500 |  | $ 5,500 |  |  |
Additional annual costs |  |  |  |  | 100 |  |
Base rate amount |  |  |  | $ 245,500 |  |  |
Return on equity |  |  |  | 9.60% |  |  |
Regulatory liabilities |  |  |  |  | 24,200 | $ 34,600 |
Deferred income tax benefits |  |  |  | $ 28,700 |  |  |
Amortization period |  |  |  | 4 years |  |  |
New Jersey Board Of Public Utilities [Member] | Pinelands Water Company [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  | 500 |  |
New Jersey Board Of Public Utilities [Member] | Pinelands Wastewater [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  | 700 |  |
Pennsylvania Public Utilities Commissio [Member] | Twin Lakes [Member] |  |  |  |  |  |  |
Regulatory Liabilities [Line Items] |  |  |  |  |  |  |
Approved increase in annual operating revenues |  |  |  |  | $ 200 |  |

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