Contract Extension To Construct Pipeline

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Investments in parties associated with the reporting entity net of guarantees to be paid by the reporting entity (which are included as liabilities on the balance sheet).

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The maximum exposure to loss (i.e. risk) to the reporting entity should the affiliates (the parties associated with the reporting entity) become unable to continue operations.

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The amount of net investments in, and advances to unconsolidated affiliates reported by an equity method investment of the entity.

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Notes Receivable, Accrued Interest, Related Parties

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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Contractual interest rate for funds borrowed, under the debt agreement.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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Amount of revenue, fees and commissions earned from transactions between (a) a parent company and its subsidiaries; (b) subsidiaries of a common parent; (c) an entity and trusts for the benefit of employees, for example, but not limited to, pension and profit-sharing trusts that are managed by or under the trusteeship of the entity's management; (d) an entity and its principal, owners, management, or members of their immediate families; and (e) affiliates.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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AFFILIATIONS, DISCONTINUED OPERATIONS AND RELATED-PARTY TRANSACTIONS - Narrative (Details) - USD ($) $ in Thousands		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
	Feb. 20, 2020	Dec. 31, 2019	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Schedule of Equity Method Investments [Line Items]
Investment		$ 87,087	$ 91,323		$ 91,323		$ 87,087
Investments in unconsolidated affiliates					2,000	$ 3,900
Notes receivable - affiliate		18,100	15,400		15,400		18,100
Net asset - included in investment in affiliates and other noncurrent liabilities		$ 87,100	$ 91,300		91,300		87,100
Combined equity contributions and the notes receivable - affiliate					$ 106,700		105,200
PennEast Pipeline Company, LLC (PennEast)
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			20.00%		20.00%
Contract extension to construct pipeline (in years)	2 years	2 years
Investment		$ 82,700	$ 86,900		$ 86,900		82,700
Energenic US LLC
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			50.00%		50.00%
Millennium Account Services, LLC
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			50.00%		50.00%
Potato Creek, LLC (Potato Creek)
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			30.00%		30.00%
EnerConnex, LLC
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			25.00%		25.00%
Secured Debt
Schedule of Equity Method Investments [Line Items]
Notes receivable - affiliate		$ 13,100	$ 13,100		$ 13,100		$ 13,100
Interest rate		7.50%	7.50%		7.50%		7.50%
Notes receivable, accrued interest, from affiliate		$ 4,400	$ 4,400		$ 4,400		$ 4,400
Unsecured promissory notes
Schedule of Equity Method Investments [Line Items]
Notes receivable - affiliate		$ 5,000	$ 2,300		$ 2,300		$ 5,000
South Jersey Energy Company \| EnergyMark
Schedule of Equity Method Investments [Line Items]
Equity interest (as a percent)			33.00%		33.00%
SJRG \| EnergyMark
Schedule of Equity Method Investments [Line Items]
Total operating revenue, affiliates			$ 3,500	$ 5,300	$ 8,700	$ 19,200