DERIVATIVE INSTRUMENTS - INTEREST RATE SWAPS (Details)	Dec. 31, 2020 USD ($)
Interest rate contract
Derivative [Line Items]
Fair value of interest rate derivatives terminated	$ 8,200,000
South Jersey Gas Company \| Interest Rate Swap, 12,500,000, Contract 1
Derivative [Line Items]
Notional Amount	$ 12,500,000
Fixed Interest Rate	3.53%
South Jersey Gas Company \| Interest Rate Swap, 12,500,000, Contract 2
Derivative [Line Items]
Notional Amount	$ 12,500,000
Fixed Interest Rate	3.43%

Fixed interest rate related to the interest rate derivative.

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1B
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5580258-113959

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 1A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=121590274&loc=SL5579245-113959

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- Definition

Fair value of all derivatives designated as interest rate fair value hedging instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=117331979&loc=d3e41228-113958

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