GOODWILL AND IDENTIFIABLE INTANGIBLE ASSETS - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Goodwill [Line Items]
Goodwill	$ 706,960,000		$ 706,960,000		$ 706,960,000
Amortization expense	200,000	$ 1,500,000	1,700,000	$ 2,900,000
Impairment of identifiable intangible assets	0	0	0	0
Goodwill impairment	0	$ 0	0	$ 0
ETG Utility Operations
Goodwill [Line Items]
Goodwill	700,200,000		700,200,000		700,200,000
Retail Services
Goodwill [Line Items]
Goodwill	$ 6,800,000		$ 6,800,000		$ 6,800,000