-- None. No documentation exists for this element. --

No definition available.

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Data Type:	xbrli:stringItemType
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- Definition

Due from Affiliate, Noncurrent, Secured By Property, Plant, And Equipment

+ References

No definition available.

+ Details

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Namespace Prefix:	sji_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Due from Affiliate, Noncurrent, Unsecured

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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).

+ References

No definition available.

+ Details

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Namespace Prefix:	sji_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Length of Pipeline

+ References

No definition available.

+ Details

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- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	sji_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	sji_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

No definition available.

+ Details

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Namespace Prefix:	sji_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22(a)(1))

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 323

-SubTopic 10

-Section 50

-Paragraph 3

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=6382943&loc=d3e33918-111571

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DISCONTINUED OPERATIONS AND AFFILIATIONS 2 (Details) $ in Millions	6 Months Ended
	Jun. 30, 2015 USD ($) mi	Jun. 30, 2014 USD ($)	Dec. 31, 2014 USD ($)
Affiliations [Abstract]
Investments in unconsolidated affiliates	$ 1.3	$ 3.7
Notes Receivable - affiliate	48.4		$ 51.5
Due from Affiliate, Noncurrent, Secured By Property, Plant, And Equipment	$ 39.2
Interest accrual on secured notes receivable	7.50%
Due from Affiliate, Noncurrent, Unsecured	$ 9.2
Net asset - included in investment in affiliates and other noncurrent liabilities	51.1
Combined equity contributions and the notes receivable - affiliate	$ 100.3
Energenic US LLC
Affiliations [Abstract]
Equity interest	50.00%
Potato Creek, LLC (Potato Creek)
Affiliations [Abstract]
Equity interest	30.00%
PennEast Pipeline Company, LLC (PennEast)
Affiliations [Abstract]
Equity interest	20.00%
Length of Pipeline (in miles) \| mi	100