SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021 USD ($)	Jun. 30, 2020	Jun. 30, 2021 USD ($)	Jun. 30, 2020 USD ($)	Dec. 31, 2020 USD ($)
Significant Accounting Policies [Line Items]
Number of natural gas distribution services customers	2,200,000		2,200,000
Segment Reporting, Disclosure of Major Customers	no	—	—	—
Capital Expenditures Incurred but Not yet Paid			$ 7,500	$ 6,900
Allowance for Doubtful Accounts, Premiums and Other Receivables	$ 20,500		$ 20,500		$ 16,600