Length of Pipeline

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- Definition

Number of Counties in which Entity Operates

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- Definition

Costs (net of amortization) that are capitalized under the full cost method of accounting related to interests in proved and unproved properties.

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No definition available.

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The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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The adjustment to expense previously capitalized costs of drilling exploratory wells when proved reserves are not found or when the entity obtains information that raises substantial doubt about the economic or operational viability of the project.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount of lessee's right to use underlying asset under operating lease.

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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.

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No definition available.

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Number of common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends.

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Amount of operating expense for impairments of regulated operation.

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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	3 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details)	Mar. 31, 2019 USD ($) county mi shares	Mar. 31, 2018 USD ($)	Jan. 01, 2019 USD ($)	Dec. 31, 2018 USD ($) shares	Jul. 01, 2018 USD ($)
Accounting Policies [Abstract]
Length of pipeline (in miles) \| mi	118
Amount of costs related to interests in proved and unproved properties in Pennsylvania, net of amortization				$ 8,600,000
Shares of treasury stock held (in shares) \| shares	220,339			233,482
Goodwill	$ 734,607,000			$ 734,600,000	$ 731,029,000
Public Utilities, General Disclosures [Line Items]
Operating lease right of use asset	2,700,000		$ 3,100,000
Current portion of long-term debt	333,909,000			733,909,000
Impairment charge		$ 0
Identified impairments	0	0
SJG Utility Operations
Public Utilities, General Disclosures [Line Items]
Operating lease right of use asset	400,000		$ 500,000
Current portion of long-term debt	$ 18,909,000			$ 18,909,000
Number of counties in which entity operates \| county	7
Impairment charge	$ 0	$ 0
Elizabethtown Gas
Public Utilities, General Disclosures [Line Items]
Number of counties in which entity operates \| county	7
Series 2018D Senior Notes, Due 2019
Public Utilities, General Disclosures [Line Items]
Early repayment of senior debt	$ 400,000,000