REVENUE (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Disaggregation of Revenue [Line Items]
Total revenues from alternative revenue programs	$ (3.1)	$ 8.8	$ 44.6	$ 21.3
SJG
Disaggregation of Revenue [Line Items]
Total revenues from alternative revenue programs	$ (0.2)	$ 8.8	$ 37.0	$ 26.0