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v3.20.2

REGULATORY PROCEEDINGS (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Jun. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019 | Dec. 31, 2018 | Jun. 30, 2020
Other Proceedings [Abstract] |  |  |  |  |  |  |  |
Cumulative DSIC Rate | 7.41% |  | 7.41% | 7.41% |  |  | 5.55% | 7.50%
Net Eligible Plant Improvements - Cumulative Dollars |  |  | $ 43.1 | $ 43.1 |  | $ 43.1 | $ 30.4 |
Delaware [Member] |  |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |  |
Percentage of gross water sales |  |  |  | 15.00% |  |  |  |
Period to complete rate case by law |  |  |  | 7 months |  |  |  |
Revenue returned to customers as a result of TCJA |  |  |  | $ 3.8 |  |  |  |
Delaware [Member] | Maximum [Member] |  |  |  |  |  |  |  |
Rate Proceedings [Abstract] |  |  |  |  |  |  |  |
Temporary annual rate increase subject to 15% gross water sales limitation |  |  |  | $ 2.5 |  |  |  |
Percentage of rate relief allowed should a rate case not complete |  |  |  | 15.00% |  |  |  |
Other Proceedings [Abstract] |  |  |  |  |  |  |  |
Distribution System Improvement Charge rate increase applied between base rate filings |  |  |  | 7.50% |  |  |  |
Distribution System Improvement Charge rate increase within a 12-month period |  |  |  | 5.00% |  |  |  |
Artesian Water [Member] |  |  |  |  |  |  |  |
Other Proceedings [Abstract] |  |  |  |  |  |  |  |
Revenue earned in DSIC rate increases | $ 1.4 | $ 1.3 |  | $ 3.8 | $ 3.1 |  |  |

X
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