Guarantee Expiration Period

No definition available.

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- Definition

The amount of guarantee provided by an entity to another that may include performance guarantee. Performance guarantee is an agreement (contract) that requires the guarantor to make payments to a guaranteed party based on another entity's failure to perform under an obligating agreement. This may include the issuance of a performance standby letter of credit which requires the guarantor to make payments if a specified party fails to perform under a nonfinancial contractual obligation.

+ References

No definition available.

+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Long Term Contract for Asset Management Agreement, Minimum Annual Fees

+ References

No definition available.

+ Details

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Balance Type:	debit
Period Type:	duration

- Definition

Long-Term Contract For Purchase Of Electric Power, Contract Term, Maximum

+ References

No definition available.

+ Details

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Period Type:	duration

- Definition

Long-Term Contract For Purchase Of Electric Power, Contract Term, Minimum

+ References

No definition available.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

Long-term Contract for Purchase of Electric Power, Fees Paid to Supplier

+ References

No definition available.

+ Details

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

- Definition

Long-Term Contract For Purchase Of Electric Power, Plant Output Being Purchased, Maximum

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
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Period Type:	instant

- Definition

The number of environmental cleanup sites for which costs have been incurred and recorded.

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Percentage of personnel represented by collective bargaining agreements.

+ References

No definition available.

+ Details

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Namespace Prefix:	sji_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19(b),22(b))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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Period Type:	instant

- Definition

Aggregate carrying amount of the estimated litigation liability for known or estimated probable loss from litigation, which may include attorneys' fees and other litigation costs.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942415&loc=d3e14326-108349

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.25)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	credit
Period Type:	instant

- 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.

+ Details

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- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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Balance Type:	na
Period Type:	instant

- Details

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- Details

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- Details

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Period Type:

- Details

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Data Type:	na
Balance Type:
Period Type:

- Details

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Balance Type:
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- Details

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Namespace Prefix:
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Balance Type:
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- Details

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- Details

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- Details

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- Details

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COMMITMENTS AND CONTINGENCIES (Details)		3 Months Ended
COMMITMENTS AND CONTINGENCIES (Details)	Jul. 01, 2018 USD ($)	Mar. 31, 2020 USD ($) site decatherm	Dec. 31, 2019 USD ($)	Dec. 31, 2018 $ / shares
Loss Contingencies [Line Items]
Minimum annual fee for long-term asset management agreement	$ 4,250,000
Percentage of personnel represented, collective bargaining agreements		43.00%
Approximate amount accrued related to all claims		$ 3,200,000	$ 3,100,000
Standby letters of credit
Loss Contingencies [Line Items]
Total Facility		9,600,000
SJG
Loss Contingencies [Line Items]
Cumulative obligation for demand charges and reservation fees per month		$ 8,800,000
Percentage of personnel represented, collective bargaining agreements		68.00%
Approximate amount accrued related to all claims		$ 900,000	$ 900,000
SJG \| Environmental Remediation
Loss Contingencies [Line Items]
Number of sites for environmental cleanup \| site		12
SJG \| Letter of credit
Loss Contingencies [Line Items]
Total Facility		$ 800,000
SJG \| Letter of credit under separate facility
Loss Contingencies [Line Items]
Total Facility		25,100,000
ETG Utility Operations \| Letter of credit
Loss Contingencies [Line Items]
Total Facility		1,000,000.0
South Jersey Resources Group, LLC
Loss Contingencies [Line Items]
Cumulative obligation for demand charges and reservation fees per month		$ 1,600,000
Maximum purchase commitment (in dts/d) \| decatherm		672,500
Minimum length of contract		5 years
Maximum length of contract		11 years
Capital Units
Loss Contingencies [Line Items]
Corporate Unit, stated value per share (in dollars per share) \| $ / shares				$ 50
Parental Guarantee
Loss Contingencies [Line Items]
Parental guarantees		$ 11,300,000
Guarantee expiration period		2 years
ETG Utility Operations
Loss Contingencies [Line Items]
Cumulative obligation for demand charges and reservation fees per month		$ 5,200,000
Minimum annual fee for long-term asset management agreement		$ 4,250,000
ETG Utility Operations \| Environmental Remediation
Loss Contingencies [Line Items]
Number of sites for environmental cleanup \| site		5