FINANCIAL INSTRUMENTS - Financial Instruments Not Carried at Fair Value (Details) - USD ($) $ in Millions	Mar. 31, 2019	Dec. 31, 2018
Debt Instrument [Line Items]
Estimated fair value of long-term debt, including current maturities	$ 2,540.0	$ 2,910.0
Carrying amount of long-term debt, including current maturities	2,450.0	2,840.0
Unamortized debt issuance costs	25.9	27.0
SJG Utility Operations
Debt Instrument [Line Items]
Estimated fair value of long-term debt, including current maturities	907.5	895.1
Carrying amount of long-term debt, including current maturities	903.6	893.4
Unamortized debt issuance costs	$ 6.7	$ 6.8

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.

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

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- Definition

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

+ References

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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