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AFFILIATIONS, DISCONTINUED OPERATIONS AND RELATED-PARTY TRANSACTIONS - Narrative (Details) - USD ($)		1 Months Ended	3 Months Ended	12 Months Ended
	Feb. 20, 2020	Dec. 31, 2019	Jun. 30, 2021	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Affiliations [Abstract]
Impairment on Investments in Equity Method Investees			$ 87,400,000	$ 102,872,000	$ 0	$ 0
Investment				38,509,000	106,230,000
Impairment Charges				0	0	10,745,000
Net investments in unconsolidated affiliates				60,600,000	28,900,000	8,300,000
Notes receivable due from affiliate				$ 69,900,000	$ 33,900,000
Interest accrual on secured notes receivable (as a percent)				7.50%	7.50%
Net asset - included in investment in affiliates and other noncurrent liabilities				$ 38,500,000	$ 106,200,000
Combined equity contributions and the notes receivable - affiliate				108,500,000	140,100,000
PennEast
Affiliations [Abstract]
Contract extension to construct pipeline (in years)	2 years	2 years
Investment				8,200,000	$ 91,300,000
Energenic
Affiliations [Abstract]
Investment				$ 0
Millennium Account Services, LLC
Affiliations [Abstract]
Equity interest (as a percent)				50.00%
Potato Creek
Affiliations [Abstract]
Equity interest (as a percent)				30.00%
REV LNG
Affiliations [Abstract]
Equity interest (as a percent)				35.00%	35.00%
REV LNG \| Equity Method Investee
Affiliations [Abstract]
Notes receivable due from affiliate				$ 62,600,000	$ 19,300,000
Secured Debt
Affiliations [Abstract]
Notes receivable due from affiliate				2,000,000	12,100,000
Unsecured promissory notes
Affiliations [Abstract]
Notes receivable due from affiliate				$ 5,300,000	2,500,000
Midstream \| PennEast
Affiliations [Abstract]
Equity interest (as a percent)				20.00%
Marina Energy LLC \| Notes Receivable
Affiliations [Abstract]
Impairment Charges				$ 9,100,000
Marina Energy LLC \| Notes Receivable \| Accounts Receivable
Affiliations [Abstract]
Impairment Charges				6,400,000
Marina Energy LLC \| Notes Receivable \| Notes Receivable
Affiliations [Abstract]
Impairment Charges				2,700,000
Marina Energy LLC \| Cogeneration Assets
Affiliations [Abstract]
Impairment Charges				$ 6,400,000
Marina Energy LLC \| Energenic
Affiliations [Abstract]
Equity interest (as a percent)				50.00%
South Jersey Energy Company \| EnergyMark
Affiliations [Abstract]
Equity interest (as a percent)				33.00%
SJRG \| EnergyMark
Affiliations [Abstract]
Total operating revenue, affiliates				$ 25,600,000	$ 13,700,000	$ 27,800,000
Energenic \| Cogeneration Assets
Affiliations [Abstract]
Impairment Charges				$ 12,700,000