COMMITMENTS AND CONTINGENCIES - (Details) - MGP Costs [Member] $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Commitments and Contingencies [Line Items]
Number Of Former Manufactured Gas Sites Where We Own Or Retain Legal Responsibility For Environmental Conditions	12
Number of sites where regulatory closure has been achieved	5
Deferred MGP Costs, Maximum	$ 15.0
Regulatory Asset for Costs Associated with Manufactured Gas Sites	$ 29.9	$ 18.8
Number of sites with ongoing groundwater monitoring	7
Accrual for Environmental Loss Contingencies, Revision in Estimates	$ 11.2
Accrual for Environmental Loss Contingencies	$ 22.8	$ 14.5