REGULATORY PROCEEDINGS (Details) - USD ($) $ in Millions				3 Months Ended		6 Months Ended
	Nov. 20, 2020	May 29, 2020	Nov. 15, 2019	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Other Proceedings [Abstract]
Cumulative DSIC Rate	7.50%	7.41%	7.50%
Net Eligible Plant Improvements - Cumulative Dollars	$ 43.1	$ 43.1	$ 43.1
Delaware [Member]
Rate Proceedings [Abstract]
Percentage of gross water sales						15.00%
Period to complete rate case by law						7 months
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				$ 1.3	$ 1.3	$ 2.5	$ 2.4