SOUTH JERSEY GAS 10-Q 8 May 15 2015 Q1 Quarterly report Financial data

DOCUMENT_AND_ENTITY_INFORMATIO

DOCUMENT AND ENTITY INFORMATION Document	3 Months Ended
	Mar. 31, 2015	1-May-15
Document and Entity Information [Abstract]
Entity Registrant Name	SOUTH JERSEY GAS Co
Entity Central Index Key	1035216
Current Fiscal Year End Date	-19
Entity Filer Category	Non-accelerated Filer
Document Type	10-Q
Document Period End Date	31-Mar-15
Document Fiscal Year Focus	2015
Document Fiscal Period Focus	Q1
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		2,339,139

CONDENSED_STATEMENTS_OF_INCOME

CONDENSED STATEMENTS OF INCOME (UNAUDITED) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Income Statement [Abstract]
Operating Revenues	$267,658	$210,545
Operating Expenses:
Cost of Sales (Excluding depreciation)	146,102	103,293
Operations	33,358	30,312
Maintenance	3,998	3,259
Depreciation	9,591	9,056
Energy and Other Taxes	1,420	1,185
Total Operating Expenses	194,469	147,105
Operating Income	73,189	63,440
Other Income and Expense	760	1,086
Interest Charges	-5,190	-4,342
Income Before Income Taxes	68,759	60,184
Income Taxes	-26,172	-22,527
Net Income	$42,587	$37,657

CONDENSED_STATEMENTS_OF_COMPRE

CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Net Income	$42,587		$37,657
Other Comprehensive Gain - Net of Tax:
Unrealized Gain on Available-for-Sale Securities	54	[1]	62	[1]
Unrealized Gain on Derivatives - Other	2	[1]	8	[1]
Other Comprehensive Gain - Net of Tax	56	[1]	70	[1]
Comprehensive Income	$42,643		$37,727
[1]	Determined using a combined average statutory tax rate of 40% and 41% in 2015 and 2014, respectively.

CONDENSED_STATEMENTS_OF_COMPRE1

CONDENSED STATEMENTS OF COMPREHENSIVE INCOME (UNAUDITED) (Parenthetical)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Statement of Comprehensive Income [Abstract]
Combined statutory tax rate	40.00%	41.00%

CONDENSED_STATEMENTS_OF_CASH_F

CONDENSED STATEMENTS OF CASH FLOWS (UNAUDITED) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Statement of Cash Flows [Abstract]
Net Cash Provided by Operating Activities	$19,634	$31,553
Cash Flows from Investing Activities:
Capital Expenditures	-41,601	-40,674
Net Purchase of Restricted Investments in Margin Accounts	-937	-463
Investment in Long-Term Receivables	-4,658	-2,053
Proceeds from Long-Term Receivables	1,808	1,981
Net Cash Used in Investing Activities	-45,388	-41,209
Cash Flows from Financing Activities:
Net Borrowings from (Repayments of) Short-Term Credit Facilities	28,200	-17,800
Proceeds from Issuance of Long-Term Debt	0	30,000
Payments for Issuance of Long-Term Debt	0	-210
Net Cash Provided by Financing Activities	28,200	11,990
Net Increase in Cash and Cash Equivalents	2,446	2,334
Cash and Cash Equivalents at Beginning of Period	1,778	2,020
Cash and Cash Equivalents at End of Period	$4,224	$4,354

CONDENSED_BALANCE_SHEETS_UNAUD

CONDENSED BALANCE SHEETS (UNAUDITED) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Property, Plant and Equipment:
Utility Plant, at original cost	$2,042,333		$2,002,966
Accumulated Depreciation	-419,223		-413,597
Property, Plant and Equipment - Net	1,623,110		1,589,369
Investments:
Available-for-Sale Securities	9,048		8,894
Restricted Investments	8,898		7,961
Total Investments	17,946		16,855
Current Assets:
Cash and Cash Equivalents	4,224		1,778
Accounts Receivable	164,014		60,535
Accounts Receivable - Related Parties	23,430		1,157
Unbilled Revenues	47,629		49,910
Provision for Uncollectibles	-8,620		-6,601
Natural Gas in Storage, average cost	5,611		25,325
Materials and Supplies, average cost	1,106		1,104
Deferred Income Taxes - Net	37,472		44,064
Prepaid Taxes	3,374		13,601
Derivatives - Energy Related Assets	1		2,051
Other Prepayments and Current Assets	10,018		3,688
Total Current Assets	288,259		196,612
Regulatory and Other Noncurrent Assets:
Regulatory Assets	335,009		357,160
Unamortized Debt Issuance Costs	7,186		7,382
Long-Term Receivables	17,679		15,223
Other	2,731		3,071
Total Regulatory and Other Noncurrent Assets	362,605		382,836
Total Assets	2,291,920		2,185,672
Common Equity:
Common Stock, Par Value $2.50 per share: Authorized - 4,000,000 shares Outstanding - 2,339,139 shares	5,848		5,848
Other Paid-In Capital and Premium on Common Stock	250,899		250,899
Accumulated Other Comprehensive Loss	-14,423	[1]	-14,479	[1]
Retained Earnings	480,887		438,300
Total Common Equity	723,211		680,568
Long-Term Debt	507,091		507,091
Total Capitalization	1,230,302		1,187,659
Current Liabilities:
Notes Payable	129,600		101,400
Current Portion of Long-Term Debt	35,909		35,909
Accounts Payable - Commodity	24,286		22,359
Accounts Payable - Other	36,102		32,711
Accounts Payable - Related Parties	11,092		11,249
Derivatives - Energy Related Liabilities	5,781		6,305
Customer Deposits and Credit Balances	15,391		17,626
Environmental Remediation Costs	36,498		28,480
Taxes Accrued	8,274		1,177
Pension Benefits	1,515		1,515
Interest Accrued	4,944		6,099
Other Current Liabilities	4,706		6,580
Total Current Liabilities	314,098		271,410
Regulatory and Other Noncurrent Liabilities:
Regulatory Liabilities	66,526		41,899
Deferred Income Taxes - Net	451,120		435,022
Environmental Remediation Costs	88,263		95,828
Asset Retirement Obligations	42,069		41,976
Pension and Other Postretirement Benefits	82,442		95,241
Investment Tax Credits	111		149
Derivatives - Energy Related Liabilities	1,016		1,298
Derivatives - Other	8,330		7,325
Other	7,643		7,865
Total Regulatory and Other Noncurrent Liabilities	747,520		726,603
Commitments and Contingencies
Total Capitalization and Liabilities	$2,291,920		$2,185,672
[1]	Determined using a combined average statutory tax rate of 40%.

CONDENSED_BALANCE_SHEETS_UNAUD1

CONDENSED BALANCE SHEETS (UNAUDITED) (Parenthetical) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Statement of Financial Position [Abstract]
Common Stock, Par Value (in dollars per share)	$2.50	$2.50
Authorized (in shares)	4,000,000	4,000,000
Outstanding (in shares)	2,339,139	2,339,139

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES:
	THE ENTITY - South Jersey Industries, Inc. (SJI) owns all of the outstanding common stock of South Jersey Gas Company (SJG or the Company), a regulated natural gas utility. SJG distributes natural gas in the seven southern most counties of New Jersey. In our opinion, the condensed financial statements reflect all normal and recurring adjustments needed to fairly present our financial position and operating results at the dates and for the periods presented. SJG’s business is subject to seasonal fluctuations and accordingly, this interim financial information should not be the basis for estimating the full year’s operating results. As permitted by the rules and regulations of the Securities and Exchange Commission, the accompanying condensed financial statements contain certain condensed financial information and exclude certain note disclosures normally included in annual audited financial statements prepared in accordance with accounting principles generally accepted in the United States of America (GAAP). These condensed financial statements should be read in conjunction with SJG’s Annual Report on Form 10-K for the year ended December 31, 2014 for a more complete discussion of our accounting policies and certain other information.
	REVENUE AND THROUGHPUT - BASED TAXES - SJG collects certain revenue-based energy taxes from its customers. Such taxes include New Jersey State Sales Tax and Public Utilities Assessment (PUA). State sales tax is recorded as a liability when billed to customers and is not included in revenue or operating expenses. The PUA is included in both revenues and energy and other taxes, and totaled $0.6 million and $0.4 million for the three months ended March 31, 2015 and 2014, respectively.
	NEW ACCOUNTING PRONOUNCEMENTS — Other than as described below, no new accounting pronouncement issued or effective during 2015 or 2014 had, or is expected to have, a material impact on the condensed financial statements.
	In May 2014, the Financial Accounting Standards Board (FASB) issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), This ASU supersedes the revenue recognition requirements in FASB ASC 605, Revenue Recognition, and in most industry-specific topics. The new guidance identifies how and when entities should recognize revenue. The new rules establish a core principle requiring the recognition of revenue to depict the transfer of promised goods or service to customers in an amount reflecting the consideration to which the entity expects to be entitled in exchange for such goods or services. The new guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. Management is currently determining the impact that adoption of this guidance will have on the Company's financial statement results.
	In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40); Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. The new guidance requires management of a company to evaluate whether there is substantial doubt about the company's ability to continue as a going concern. This ASU is effective for the annual reporting period ending after December 15, 2016, and for interim and annual reporting periods thereafter, with early adoption permitted. Management does not expect this standard to have an impact on the Company's financial statements upon adoption.
	In February 2015, the FASB issued ASU 2015-02, Consolidation (Topic 810)—Amendments to the Consolidation Analysis, which changes the analysis to be performed in determining whether certain types of legal entities should be consolidated. Specifically, the standard amends the evaluation of whether (a) fees paid to a decision maker or service providers represent a variable interest, (b) a limited partnership or similar entity has the characteristics of a Variable Interest Entity ("VIE") and (c) a reporting entity is the primary beneficiary of a VIE. The standard is effective for annual periods beginning after December 15, 2015 and interim periods therein, with early adoption permitted. Management is currently determining the impact that adoption of this guidance will have on the Company's financial statement results.
	In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. This ASU requires debt issuance costs to be presented in the balance sheet as a direct deduction from the associated debt liability. The standard is effective for annual periods beginning after December 15, 2015 and interim periods therein. Management is currently determining the impact that adoption of this guidance will have on the Company's financial statement results.

STOCKBASED_COMPENSATION_PLANS

STOCK-BASED COMPENSATION PLANS	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION PLANS	STOCK-BASED COMPENSATION PLANS:
	Officers and other key employees of SJG participate in the Stock-Based Compensation Plan (Plan) of SJI. Restricted performance-based shares issued under the Plan vest over a three-year period and are subject to SJI achieving certain market or earnings-based performance targets as compared to a peer group average, which can cause the actual amount of shares that ultimately vest to range from between 0% to 200% of the original share units granted. Beginning in 2015, SJI also began granting time-based shares of restricted stock, one-third of which vests annually over a three-year period and is limited to 100% payout if the service requirement is met. In January 2015, SJG officers and other key employees were granted 7,366 shares of time-based restricted stock.
	Grants containing market-based performance targets use SJI's total shareholder return (TSR) relative to a peer group to measure performance. As TSR-based grants are contingent upon market and service conditions, SJI is required to measure and recognize stock-based compensation expense based on the fair value at the date of grant on a straight-line basis over the requisite three-year period of each award. In addition, SJI identifies specific forfeitures of share-based awards, and compensation expense is adjusted accordingly over the requisite service period. Compensation expense is not adjusted based on the actual achievement of performance goals. The fair value of TSR-based restricted stock awards on the date of grant is estimated using a Monte Carlo simulation model.
	Through 2014, grants containing earnings-based targets were based on SJI's earnings per share (EPS) growth rate relative to a peer group to measure performance. Beginning in 2015, earning-based performance targets include predefined EPS and return on equity (ROE) goals to measure performance. As EPS-based and ROE-based grants are contingent upon performance and service conditions, SJI is required to measure and recognize stock-based compensation expense based on the fair value at the date of grant over the requisite three-year period of each award. The fair value is measured as the market price at the date of grant. The initial accruals of compensation expense are based on the estimated number of shares expected to vest, assuming the requisite service is rendered and probable outcome of the performance condition is achieved. That estimate is revised if subsequent information indicates that the actual number of shares is likely to differ from previous estimates. Compensation expense is ultimately adjusted based on the actual achievement of service and performance targets.
	We are allocated a portion of SJI's compensation cost during the vesting period.  We accrue a liability and record compensation cost over the requisite three-year service period based on the grant date fair value as described above for each type of grant. Upon vesting, we make a cash payment to SJI equal to the amounts accrued as compensation cost during the vesting period. Since the inception of the Plan, our expense recognition policy has been consistent with the expense recognition policy at SJI.
	The following table summarizes the SJI nonvested restricted stock awards pertaining to SJG outstanding at March 31, 2015, and the assumptions used to estimate the fair value of the awards:
	Grant Date		Shares		Fair Value		Expected		Risk-Free
			Outstanding		Per Share		Volatility		Interest Rate
	Jan. 2013 - TSR		8,002		$	22.19	21.1	%	0.4	%
	Jan. 2013 - EPS		8,002		$	25.59	n/a		n/a
	Jan. 2014 - TSR		10,394		$	21.31	20	%	0.8	%
	Jan. 2014 - EPS		10,394		$	27.22	n/a		n/a
	Jan. 2015 - TSR		6,874		$	26.31	16	%	1.1	%
	Jan. 2015 - EPS, ROE, Time		17,686		$	29.47	n/a		n/a
	Expected volatility is based on the actual volatility of SJI’s share price over the preceding three-year period as of the valuation date. The risk-free interest rate is based on the zero-coupon U.S. Treasury Bond, with a term equal to the three-year term of the restricted shares. As notional dividend equivalents are credited to the holders during the three-year service period, no reduction to the fair value of the award is required.
	The cost for restricted stock awards during 2015 and 2014 is approximately $0.1 million per quarter. Of these costs, approximately one half was capitalized to Utility Plant.
	As of March 31, 2015, there was $1.0 million of total unrecognized compensation cost related to nonvested share-based compensation awards granted under the Plan. That cost is expected to be recognized over a weighted average period of 2.2 years.
	The following table summarizes information regarding restricted stock award activity during the three months ended March 31, 2015, excluding accrued dividend equivalents:
		Shares		Weighted
				Average
				Grant Date
				Fair Value
	Nonvested Shares Outstanding, January 1, 2015	36,794		$	24.1
	Granted	24,560		$	28.58
	Nonvested Shares Outstanding, March 31, 2015	61,354		$	25.9
	Performance targets during the three-year vesting periods were not attained for the January 2011 grant that vested at December 31, 2013, or the January 2012 grant that vested at December 31, 2014. As a result, no shares were awarded in 2014 or 2015. SJG has a policy of making cash payments to SJI to satisfy its obligations under the Plan. Cash payments to SJI during the three months ended March 31, 2015 and 2014 were approximately $0.2 million and $0.4 million, respectively, relating to stock awards. Additionally, a change in control could result in the nonvested shares becoming nonforfeitable or immediately payable in cash.

RATES_AND_REGULATORY_ACTIONS

RATES AND REGULATORY ACTIONS	3 Months Ended
	Mar. 31, 2015
Public Utilities, General Disclosures [Abstract]
RATES AND REGULATORY ACTIONS	RATES AND REGULATORY ACTIONS:
	SJG is subject to the rules and regulations of the New Jersey Board of Public Utilities (BPU).
	Effective October 1, 2014, the BPU granted SJG a base rate increase of $20 million, which was predicated in part upon a 7.10% rate of return on rate base that included a 9.75% return on common equity. The $20 million base rate increase includes approximately $7.5 million associated with previously approved Accelerated Infrastructure Replacement Program (AIRP) investments that were rolled into rate base. SJG was also permitted to recover regulatory assets contained in its petition and reduce its composite depreciation rate from 2.4% to 2.1%.
	In January 2015, SJG filed a petition with the BPU seeking to continue offering energy efficiency programs through June 2018 with a proposed budget of $56 million and with the same rate recovery mechanism that exists for its current energy efficiency programs.
	There have been no other significant regulatory actions or changes to SJG's rate structure since December 31, 2014. See Note 3 to the Financial Statements in Item 8 of SJG's Form 10-K for the year ended December 31, 2014.

REGULATORY_ASSETS_AND_LIABILIT

REGULATORY ASSETS AND LIABILITIES	3 Months Ended
	Mar. 31, 2015
Regulatory Assets and Liabilities Disclosure [Abstract]
REGULATORY ASSETS AND LIABILITIES	REGULATORY ASSETS AND LIABILITIES:
	There have been no significant changes to the nature of SJG’s regulatory assets and liabilities since December 31, 2014, which are described in Notes 3 and 4 to the Financial Statements in Item 8 of SJG’s Form 10-K for the year ended December 31, 2014.
	Regulatory Assets consisted of the following items (in thousands):
		March 31, 2015		December 31, 2014
	Environmental Remediation Costs:
	Expended - Net	$	28,057	$	29,540
	Liability for Future Expenditures	124,761		124,308
	Deferred Asset Retirement Obligation Costs	31,604		31,584
	Deferred Pension and Other Postretirement Benefit Costs	99,040		99,040
	Deferred Gas Costs - Net	20,291		32,202
	Societal Benefit Costs Receivable	—		385
	Deferred Interest Rate Contracts (Note 11)	8,330		7,325
	Energy Efficiency Tracker	1,782		11,247
	Pipeline Supplier Service Charges	5,025		5,441
	Pipeline Integrity Cost	3,439		3,431
	AFUDC - Equity Related Deferrals	10,987		10,781
	Other Regulatory Assets	1,693		1,876
	Total Regulatory Assets	$	335,009	$	357,160
	DEFERRED GAS COSTS - NET - Over/under collections of gas costs are monitored through SJG's Basic Gas Supply Service (BGSS) mechanism. Net undercollected gas costs are classified as a regulatory asset and net overcollected gas costs are classified as a regulatory liability. Derivative contracts used to hedge natural gas purchases are also included in the BGSS, subject to BPU approval. The reduction in deferred gas costs from December 31, 2014 was due to gas costs recovered from customers exceeding the actual cost of the commodity incurred during the first three months of 2015 as a result of more normal gas prices. SJG's BGSS mechanism is designed to over-collect gas costs during the winter season when usage is highest.
	ENERGY EFFICIENCY TRACKER - This regulatory asset primarily represents energy efficiency measures installed in customer homes and businesses. The decrease from December 31, 2014 is due to higher recoveries in the first three months of 2015 due to high level of recoveries resulting from extremely cold weather.
	Regulatory Liabilities consisted of the following items (in thousands):
		March 31, 2015		December 31, 2014
	Excess Plant Removal Costs	$	35,762	$	35,940
	Conservation Incentive Program Payable	21,825		4,700
	Societal Benefit Costs	8,939		—
	Other Regulatory Liabilities	—		1,259
	Total Regulatory Liabilities	$	66,526	$	41,899
	EXCESS PLANT REMOVAL COSTS - Represents amounts accrued in excess of actual utility plant removal costs incurred to date. The decrease in the balance from year end is due to an amortization as a credit to depreciation expense, as required as part of our September 2014 base rate increase.
	CONSERVATION INCENTIVE PROGRAM (CIP) PAYABLE – The CIP tracking mechanism adjusts earnings when actual usage per customer experienced during the period varies from an established baseline usage per customer. Actual usage per customer was greater than the established baseline during 2014 and more notably during the first three months of 2015, resulting in a payable. This is primarily the result of extremely cold weather experienced in the region.
	SOCIETAL BENEFIT COSTS (SBC) - This regulatory liability primarily represents the excess recoveries over the expenses incurred under the New Jersey Clean Energy Program which is a mechanism designed to recover costs associated with energy efficiency and renewable energy programs. The change from a $0.4 million regulatory asset to an $8.9 million regulatory liability is due to current SBC rates, which are producing revenue greater than SBC expenses. In July 2014, SJG made its annual 2014-2015 SBC filing requesting a decrease in SBC revenues, in part, to avoid this liability. The petition is currently pending.

RELATEDPARTY_TRANSACTIONS

RELATED-PARTY TRANSACTIONS	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
RELATED-PARTY TRANSACTIONS	RELATED-PARTY TRANSACTIONS:
	There have been no significant changes in the nature of SJG’s related-party transactions since December 31, 2014. See Note 5 to the Financial Statements in Item 8 of SJG’s Form 10-K for the year ended December 31, 2014 for a detailed description of the related parties and their associated transactions.
	A summary of related party transactions, excluding pass-through items, included in Operating Revenues were as follows (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Operating Revenues/Affiliates:
	SJRG	$	1,052		$	158
	Marina	232			333
	Total Operating Revenue/Affiliates	$	1,284		$	491
	Related-party transactions, excluding pass-through items, included in Operating Expenses were as follows (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Costs of Sales/Affiliates (Excluding depreciation)
	SJRG	$	19,023		$	5,484
	Energy-Related Derivative (Gains) / Losses *
	SJRG	$	(4	)	$	(1,030	)
	* Contracts used to hedge natural gas purchases. Included in Cost of Sales on the Condensed Statement of Income.
	Operations Expense/Affiliates
	SJI	$	3,917		$	4,030
	Millennium	660			608
	Other	(109		)	(104		)
	Total Operations Expense/Affiliates	$	4,468		$	4,534

FINANCIAL_INSTRUMENTS

FINANCIAL INSTRUMENTS	3 Months Ended
	Mar. 31, 2015
Financial Instruments, Owned, at Fair Value [Abstract]
FINANCIAL INSTRUMENTS	FINANCIAL INSTRUMENTS:
	RESTRICTED INVESTMENTS - In accordance with the terms of our tax-exempt first mortgage bonds, unused proceeds are required to be escrowed pending approved construction expenditures. As of both March 31, 2015 and December 31, 2014, the escrowed proceeds, including interest earned, totaled $0.1 million. During March 2013, SJG established a margin account with a counterparty in conjunction with SJG's risk management activities as detailed in Note 11. The funds provided by SJG will increase or decrease as the number and value of outstanding energy-related contracts held with this counterparty change. As of March 31, 2015 and December 31, 2014, the balance held with this counterparty totaled $8.8 million and 7.8 million, respectively. The carrying amounts of the Restricted Investments approximate their fair value at March 31, 2015 and December 31, 2014, which would be included in Level 1 of the fair value hierarchy. (See Note 10 - Fair Value of Financial Assets and Financial Liabilities.)
	LONG-TERM RECEIVABLES – SJG provides financing to customers for the purpose of attracting conversions to natural gas heating systems from competing fuel sources.  The terms of these loans call for customers to make monthly payments over a period of up to five years with no interest.  The carrying amounts of such loans were $14.9 million and $15.0 million as of March 31, 2015 and December 31, 2014, respectively.  The current portion of these receivables is reflected in Accounts Receivable and the non-current portion is reflected in Long-Term Receivables on the condensed balance sheets.  The carrying amounts noted above are net of unamortized discounts resulting from imputed interest in the amount of $1.2 million and $1.3 million as of March 31, 2015 and December 31, 2014, respectively.  The annualized amortization to interest is not material to SJG’s financial statements.  The carrying amounts of these receivables approximate their fair value at March 31, 2015 and December 31, 2014, which would be included in Level 2 of the fair value hierarchy. (See Note 10 - Fair Value of Financial Assets and Financial Liabilities.)
	FINANCIAL INSTRUMENTS NOT CARRIED AT FAIR VALUE - The fair value of a financial instrument is the market price to sell an asset or transfer a liability at the measurement date. The carrying amounts of SJG's financial instruments approximate their fair values at March 31, 2015 and December 31, 2014, except as noted below.
	•	For Long-Term Debt, in estimating the fair value, we use the present value of remaining cash flows at the balance sheet date. We based the estimates on interest rates available to SJG at the end of each period for debt with similar terms and maturities (Level 2 in the fair value hierarchy. See Note 10 - Fair Value of Financial Assets and Financial Liabilities). The estimated fair values of SJG's long-term debt, including current maturities, as of March 31, 2015 and December 31, 2014, were $595.8 million and $587.3 million, respectively. The carrying amount of SJG's long-term debt, including current maturities, as of both March 31, 2015 and December 31, 2014 was $543.0 million.

LINES_OF_CREDIT

LINES OF CREDIT	3 Months Ended
	Mar. 31, 2015
Line of Credit Facility [Abstract]
LINES OF CREDIT	LINES OF CREDIT:
	Credit facilities and available liquidity as of March 31, 2015 were as follows (in thousands):
		Total Facility		Usage		Available Liquidity		Expiration Date
	Commercial Paper Program/ Revolving Credit Facility	$	200,000	$	129,600	$	70,400	May-18
	Uncommitted Bank Lines	10,000		—		10,000		Various
	Total	$	210,000	$	129,600	$	80,400
	The SJG revolving credit facility is provided by a syndicate of banks and contains one financial covenant limiting the ratio of indebtedness to total capitalization (as defined in the credit agreement) to not more than 0.65 to 1 measured at the end of each fiscal quarter.  SJG was in compliance with this covenant as of March 31, 2015.
	SJG manages a commercial paper program under which SJG may issue short-term, unsecured promissory notes to qualified investors up to a maximum aggregate amount outstanding at any time of $200.0 million.  The notes  have fixed maturities which vary by note, but may not exceed 270 days from the date of issue. Proceeds from the notes are used for general corporate purposes.  SJG uses the commercial paper program in tandem with the $200.0 million revolving credit facility and does not expect the principal amount of borrowings outstanding under the commercial paper program and the credit facility at any time to exceed an aggregate of $200.0 million.
	Average borrowings outstanding under these credit facilities during the three months ended March 31, 2015 and 2014 were $108.5 million and $40.8 million, respectively.  The maximum amount outstanding under these credit facilities during the three months ended March 31, 2015 and 2014 were $136.9 million and $66.0 million, respectively.
	Based upon the existing credit facilities and a regular dialogue with our banks, we believe that there will continue to be sufficient credit available to meet our business’ future liquidity needs. Borrowings under these credit facilities are at market rates.  The weighted average interest rate on these borrowings, which changes daily, was 0.50% and 0.25% at March 31, 2015 and 2014, respectively.

PENSION_AND_OTHER_POSTRETIREME

PENSION AND OTHER POSTRETIREMENT BENEFITS	3 Months Ended
	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
PENSION AND OTHER POSTRETIREMENT BENEFITS	PENSION AND OTHER POSTRETIREMENT BENEFITS:
	For the three months ended  March 31, 2015 and 2014, net periodic benefit cost related to the employee and officer pension and other postretirement benefit plans consisted of the following components (in thousands):
		Pension Benefits
		Three Months Ended
		March 31,
		2015			2014
	Service Cost	$	1,067		$	966
	Interest Cost	2,048			2,027
	Expected Return on Plan Assets	(2,734		)	(2,455		)
	Amortizations:
	Prior Service Cost	39			33
	Actuarial Loss	1,963			1,072
	Net Periodic Benefit Cost	2,383			1,643
	Capitalized Benefit Costs	(1,239		)	(854		)
	Total Net Periodic Benefit Expense	$	1,144		$	789
		Other Postretirement Benefits
		Three Months Ended
		March 31,
		2015			2014
	Service Cost	$	182		$	172
	Interest Cost	429			510
	Expected Return on Plan Assets	(416		)	(473		)
	Amortizations:
	Prior Service Cost	85			26
	Actuarial Loss	214			167
	Net Periodic Benefit Cost	494			402
	Capitalized Benefit Costs	(257		)	(209		)
	Total Net Periodic Benefit Expense	$	237		$	193
	Capitalized benefit costs reflected in the table above relate to our construction program.
	SJG contributed $12.0 million to the pension plans in January 2015. No contributions were made to the pension plans during 2014. Payments related to the unfunded Supplemental Executive Retirement Plan (SERP) are expected to approximate $1.5 million in 2015. We also have a regulatory obligation to contribute approximately $3.6 million annually to the other postretirement benefit plans’ trusts, less direct costs incurred.
	See Note 11 to the Financial Statements in Item 8 of SJG’s Form 10-K for the year ended December 31, 2014 for additional information related to SJG’s pension and other postretirement benefits.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	3 Months Ended
	Mar. 31, 2015
Commitments and Contingencies Disclosure [Abstract]
COMMITMENTS AND CONTINGENCIES	COMMITMENTS AND CONTINGENCIES:
	STANDBY LETTER OF CREDIT - SJG provided a $25.2 million letter of credit under a separate facility outside of its revolving credit facility to support variable-rate demand bonds issued through the New Jersey Economic Development Authority (NJEDA) to finance the expansion of SJG’s natural gas distribution system.
	ENVIRONMENTAL REMEDIATION COSTS - SJG incurred and recorded costs for environmental cleanup of 12 sites where SJG or its predecessors operated gas manufacturing plants. SJG stopped manufacturing gas in the 1950s. There have been no significant changes to the status of SJG’s environmental remediation efforts since December 31, 2014, as described in Note 12 to the Financial Statements in Item 8 of SJG’s Form 10-K for the year ended December 31, 2014.
	GAS SUPPLY RELATED CONTRACTS - In the normal course of conducting business, we have entered into long-term contracts for natural gas supplies, firm transportation and gas storage service. The earliest date at which any of the primary terms of these contracts expire is October 2017. The transportation and storage agreements entered into between us and each of our interstate pipeline service providers were done so in accordance with their respective FERC-approved tariff. Our cumulative obligation for gas supply related demand charges and reservation fees paid for these services averages approximately $3.9 million per month and is recovered on a current basis through the BGSS.
	PENDING LITIGATION - We are subject to claims arising in the ordinary course of business and other legal proceedings. We accrue liabilities related to these claims when we can reasonably estimate the amount or range of amounts of probable settlement costs or other charges for these claims. The Company has accrued approximately $0.8 million and $0.5 million related to all claims in the aggregate as of March 31, 2015 and December 31, 2014, respectively. Management does not believe that it is reasonably possible that there will be a material change in the Company's estimated liability in the near term and does not currently anticipate the disposition of any known claims that would have a material effect on the Company's financial position, results of operations or cash flows.
	COLLECTIVE BARGAINING AGREEMENTS - Unionized personnel represent approximately 60% of our workforce at March 31, 2015. The Company has collective bargaining agreements with two unions who represent these employees: the International Brotherhood of Electrical Workers (IBEW) operates under a collective bargaining agreement that runs through February 2017; and the International Association of Machinists and Aerospace Workers (IAM) operates under a collective bargaining agreement that expires in August 2017.

FAIR_VALUE_OF_FINANCIAL_ASSETS

FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES	FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES:
	GAAP establishes a hierarchy that prioritizes fair value measurements based on the types of inputs used for the various valuation techniques.  The levels of the hierarchy are described below:
	•	Level 1:  Observable inputs such as quoted prices in active markets for identical assets or liabilities.
	•	Level 2:  Inputs other than quoted prices that are observable for the asset or liability, either directly or indirectly; these include quoted prices for similar assets or liabilities in active markets and quoted prices for identical or similar assets or liabilities in markets that are not active.
	•	Level 3:  Unobservable inputs that reflect the reporting entity’s own assumptions.
	Assessment of the significance of a particular input to the fair value measurement requires judgment and may affect the valuation of financial assets and financial liabilities and their placement within the fair value hierarchy.
	For financial assets and financial liabilities measured at fair value on a recurring basis, information about the fair value measurements for each major category is as follows (in thousands):
	As of March 31, 2015
		Total		Level 1		Level 2		Level 3
	Assets
	Available-for-Sale Securities (A)	$	9,048	$	3,619	$	5,429	$	—
	Derivatives – Energy Related Assets (B)	1		1		—		—
		$	9,049	$	3,620	$	5,429	$	—
	Liabilities
	Derivatives – Energy Related Liabilities (B)	$	6,797	$	6,506	$	291	$	—
	Derivatives – Other (C)	8,330		—		8,330		—
		$	15,127	$	6,506	$	8,621	$	—
	As of December 31, 2014
		Total		Level 1		Level 2		Level 3
	Assets
	Available-for-Sale Securities (A)	$	8,894	$	5,924	$	2,970	$	—
	Derivatives - Energy Related Assets (B)	2,051		2		2,049		—
		$	10,945	$	5,926	$	5,019	$	—
	Liabilities
	Derivatives - Energy Related Liabilities (B)	$	7,603	$	7,254	$	349	$	—
	Derivatives - Other (C)	7,325		—		7,325		—
		$	14,928	$	7,254	$	7,674	$	—
	(A)  Available-for-Sale Securities include securities that are traded in active markets and securities that are not traded publicly.  The securities traded in active markets are valued using the quoted principal market close prices that are provided by the trustees and are categorized in Level 1 in the fair value hierarchy. The remaining securities consist of funds that are not publicly traded. These funds, which consist of stocks and bonds that are traded individually in active markets, are valued using quoted prices for similar assets and are categorized in Level 2 in the fair value hierarchy.
	(B)  Derivatives – Energy Related Assets and Liabilities are traded in both exchange-based and non-exchange-based markets. Exchange-based contracts are valued using unadjusted quoted market sources in active markets and are categorized in Level 1 in the fair value hierarchy. Certain non-exchange-based contracts are valued using indicative price quotations available through brokers or over-the-counter, on-line exchanges and are categorized in Level 2. These price quotations reflect the average of the bid-ask mid-point prices and are obtained from sources that management believes provide the most liquid market. Management reviews and corroborates the price quotations to ensure the prices are observable which includes consideration of actual transaction volumes, market delivery points, bid-ask spreads and contract duration.
	(C)  Derivatives – Other, include interest rate swaps that are valued using quoted prices on commonly quoted intervals, which are interpolated for periods different than the quoted intervals, as inputs to a market valuation model.  Market inputs can generally be verified and model selection does not involve significant management judgment.

DERIVATIVE_INSTRUMENTS

DERIVATIVE INSTRUMENTS	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
DERIVATIVE INSTRUMENTS	DERIVATIVE INSTRUMENTS:
	SJG is involved in buying, selling, transporting and storing natural gas and is subject to market risk on expected future purchases and sales due to commodity price fluctuations. The Company, through its affiliate South Jersey Resources Group (SJRG) and another counterparty, uses a variety of derivative instruments to limit this exposure to market risk in accordance with strict corporate guidelines. These derivative instruments include forward contracts, futures contracts, swap agreements and options contracts. As of March 31, 2015, SJG had outstanding derivative contracts intended to limit the exposure to market risk on 11.6 million decatherms (MMdts) of expected future purchases of natural gas and 0.04 MMdts of expected future sales of natural gas. In addition to these derivative contracts, SJG had basis and index related purchase and sales contracts totaling 0.8 MMdts. These contracts, which do not qualify for the normal purchase and sale exemption and have not been designated as hedging instruments under GAAP, are measured at fair value and recorded in Derivatives — Energy Related Assets or Derivatives — Energy Related Liabilities on the condensed balance sheets. The costs or benefits of these short-term contracts are recoverable through SJG’s BGSS clause, subject to BPU approval. As a result, the net unrealized pre-tax gains and losses for these energy-related commodity contracts are included with realized gains and losses in Regulatory Assets or Regulatory Liabilities on the condensed balance sheets. As of March 31, 2015 and December 31, 2014, SJG had $6.8 million and $5.6 million of unrealized losses, respectively, included in its BGSS related to open financial contracts.
	The Company has also entered into interest rate derivatives to hedge exposure to increasing interest rates and the impact of those rates on cash flows of variable-rate debt. These interest rate derivatives, which have not been designated as hedging instruments under GAAP, are measured at fair value and recorded in Derivatives-Other on the condensed balance sheets. The fair value represents the amount SJG would have to pay the counterparty to terminate these contracts as of those dates. There have been no significant changes to the Company’s active interest rate swaps since December 31, 2014, which are described in Note 1 to the Financial Statements in Item 8 of SJG’s Annual Report on Form 10-K for the year ended December 31, 2014. Subject to BPU approval, the market value upon termination of these interest rate derivatives can be recovered in rates and, therefore, these unrealized losses have been included in Regulatory Assets on the condensed balance sheets.
	We previously used derivative transactions known as “Treasury Locks” to hedge against the impact on our cash flows of possible interest rate increases on debt issued in September 2005.  The initial $1.4 million cost of the Treasury Locks has been included in Accumulated Other Comprehensive Loss and is being amortized over the 30-year life of the associated debt issue.  As of March 31, 2015 and December 31, 2014, the unamortized balance was approximately $0.9 million, and $1.0 million, respectively .
	The fair values of all derivative instruments, as reflected in the condensed balance sheets as of March 31, 2015 and December 31, 2014, are as follows (in thousands):
	Derivatives not designated as hedging instruments under GAAP	March 31, 2015						December 31, 2014
		Assets			Liabilities			Assets			Liabilities
	Energy related commodity contracts:
	Derivatives – Energy Related – Current	$	1		$	5,781		$	2,051		$	6,305
	Derivatives – Energy Related – Non-Current	—			1,016			—			1,298
	Interest rate contracts:
	Derivatives – Other	—			8,330			—			7,325
	Total derivatives not designated as hedging instruments under GAAP	1			15,127			2,051			14,928
	Total Derivatives	$	1		$	15,127		$	2,051		$	14,928
	For derivative instruments disclosed in the table above, information as to the presentation on the condensed balance sheets is as follows (in thousands):
	As of March 31, 2015:
	Description	Gross amounts of recognized assets/liabilities			Gross amount offset in the balance sheet			Net amounts of assets/liabilities in balance sheet			Gross amounts not offset in the balance sheet						Net amount
											Financial Instruments				Cash Collateral Posted
	Derivatives - Energy Related Assets	$	1		$	—		$	1		$	(1	)	(A)	$	—	$	—
	Derivatives - Energy Related Liabilities	(6,797		)	—			(6,797		)	1			(B)	6,506		(290		)
	Derivatives - Other	(8,330		)	—			(8,330		)	—				—		(8,330		)
	As of December 31, 2014:
	Description	Gross amounts of recognized assets/liabilities			Gross amount offset in the balance sheet			Net amounts of assets/liabilities in balance sheet			Gross amounts not offset in the balance sheet						Net amount
											Financial Instruments				Cash Collateral Posted
	Derivatives - Energy Related Assets	$	2,051		$	—		$	2,051		$	(2	)	(A)	$	—	$	2,049
	Derivatives - Energy Related Liabilities	(7,603		)	—			(7,603		)	2			(B)	7,253		(348		)
	Derivatives - Other	(7,325		)	—			(7,325		)	—				—		(7,325		)
	(A) The balances at March 31, 2015 and December 31, 2014 were related to derivative liabilities which can be net settled against derivative assets.
	(B) The balances at March 31, 2015 and December 31, 2014 were related to derivative assets which can be net settled against derivative liabilities.
	The effect of derivative instruments on the condensed statements of income for the three months ended March 31, 2015 and 2014 are as follows (in thousands):
		Three months ended
		March 31,
	Derivatives in Cash Flow Hedging Relationships	2015			2014
	Interest Rate Contracts:
	Losses reclassified from Accumulated Other Comprehensive Loss into income (a)	$	(12	)	$	(12	)
	(a) Included in Interest Charges
	Net realized loss of $2.6 million and gain of $2.4 million associated with SJG's energy related financial commodity contracts for the three months ended March 31, 2015 and 2014, respectively, are not included in the above table.  These contracts are part of SJG’s regulated risk management activities that serve to mitigate BGSS costs passed on to its customers. As these transactions are entered into pursuant to, and recoverable through, regulatory riders, any changes in the value of SJG’s energy-related financial commodity contracts are deferred in Regulatory Assets or Liabilities, as applicable, and there is no impact to earnings.

LONGTERM_DEBT

LONG-TERM DEBT	3 Months Ended
	Mar. 31, 2015
Long-term Debt, Unclassified [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT:
	The Company did not issue or retire any long-term debt during the three months ended March 31, 2015. We retire debt when it is cost effective as permitted by the debt agreements.

ACCUMULATED_OTHER_COMPREHENSIV

ACCUMULATED OTHER COMPREHENSIVE LOSS	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS	ACCUMULATED OTHER COMPREHENSIVE LOSS:
	The changes in Accumulated Other Comprehensive Loss (AOCL) for the three months ended March 31, 2015 are as follows (in thousands):
		Postretirement Liability Adjustment			Unrealized Gain (Loss) on Derivatives-Other			Unrealized Gain (Loss) on Available-for-Sale Securities			Total
	Balance at January 1, 2015 (a)	$	(13,837	)	$	(567	)	$	(75	)	$	(14,479	)
	Other comprehensive income before reclassifications	—			—			92			92
	Amounts reclassified from AOCL (b)	—			2			(38		)	(36		)
	Net current period other comprehensive income	—			2			54			56
	Balance at March 31, 2015 (a)	$	(13,837	)	$	(565	)	$	(21	)	$	(14,423	)
	(a) Determined using a combined average statutory tax rate of 40%.
	(b) See table below.
	The reclassifications out of AOCL during the three months ended March 31, 2015 are as follows (in thousands):
	Components of AOCL	Amounts Reclassified from AOCL (in thousands)			Affected Line Item in the Condensed Statements of Income
		Three Months Ended
		31-Mar-15
	Unrealized Loss in on Derivatives-Other - Interest Rate Contracts designated as cash flow hedges	$	12		Interest Charges
	Unrealized Gain on Available-for-Sale Securities	(64		)	Other Income & Expense
		(52		)	Income Before Income Taxes
	Income Taxes (a)	16			Income Taxes
	Gains from reclassifications for the period net of tax	$	(36	)
	(a) Determined using a combined average statutory tax rate of 40%.

SUBSEQUENT_EVENTS

SUBSEQUENT EVENTS	3 Months Ended
	Mar. 31, 2015
Subsequent Events [Abstract]
SUBSEQUENT EVENTS	SUBSEQUENT EVENTS:
	On April 1, 2015, the Board of Directors of SJG declared a cash dividend of $9,891,000 payable to SJI. The dividend was paid on April 2, 2015.

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	3 Months Ended
	Mar. 31, 2015
Accounting Policies [Abstract]
REVENUE AND THROUGHPUT BASED TAXES	REVENUE AND THROUGHPUT - BASED TAXES - SJG collects certain revenue-based energy taxes from its customers. Such taxes include New Jersey State Sales Tax and Public Utilities Assessment (PUA). State sales tax is recorded as a liability when billed to customers and is not included in revenue or operating expenses.
NEW ACCOUNTING PRONOUNCEMENTS	NEW ACCOUNTING PRONOUNCEMENTS — Other than as described below, no new accounting pronouncement issued or effective during 2015 or 2014 had, or is expected to have, a material impact on the condensed financial statements.
	In May 2014, the Financial Accounting Standards Board (FASB) issued ASU 2014-09, Revenue from Contracts with Customers (Topic 606), This ASU supersedes the revenue recognition requirements in FASB ASC 605, Revenue Recognition, and in most industry-specific topics. The new guidance identifies how and when entities should recognize revenue. The new rules establish a core principle requiring the recognition of revenue to depict the transfer of promised goods or service to customers in an amount reflecting the consideration to which the entity expects to be entitled in exchange for such goods or services. The new guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2016. Management is currently determining the impact that adoption of this guidance will have on the Company's financial statement results.
	In August 2014, the FASB issued ASU 2014-15, Presentation of Financial Statements - Going Concern (Subtopic 205-40); Disclosure of Uncertainties about an Entity's Ability to Continue as a Going Concern. The new guidance requires management of a company to evaluate whether there is substantial doubt about the company's ability to continue as a going concern. This ASU is effective for the annual reporting period ending after December 15, 2016, and for interim and annual reporting periods thereafter, with early adoption permitted. Management does not expect this standard to have an impact on the Company's financial statements upon adoption.
	In February 2015, the FASB issued ASU 2015-02, Consolidation (Topic 810)—Amendments to the Consolidation Analysis, which changes the analysis to be performed in determining whether certain types of legal entities should be consolidated. Specifically, the standard amends the evaluation of whether (a) fees paid to a decision maker or service providers represent a variable interest, (b) a limited partnership or similar entity has the characteristics of a Variable Interest Entity ("VIE") and (c) a reporting entity is the primary beneficiary of a VIE. The standard is effective for annual periods beginning after December 15, 2015 and interim periods therein, with early adoption permitted. Management is currently determining the impact that adoption of this guidance will have on the Company's financial statement results.
	In April 2015, the FASB issued ASU 2015-03, Interest-Imputation of Interest (Subtopic 835-30): Simplifying the Presentation of Debt Issuance Costs. This ASU requires debt issuance costs to be presented in the balance sheet as a direct deduction from the associated debt liability. The standard is effective for annual periods beginning after December 15, 2015 and interim periods therein. Management is currently determining the impact that adoption of this guidance will have on the Company's financial statement results.
FAIR VALUE	(A)  Available-for-Sale Securities include securities that are traded in active markets and securities that are not traded publicly.  The securities traded in active markets are valued using the quoted principal market close prices that are provided by the trustees and are categorized in Level 1 in the fair value hierarchy. The remaining securities consist of funds that are not publicly traded. These funds, which consist of stocks and bonds that are traded individually in active markets, are valued using quoted prices for similar assets and are categorized in Level 2 in the fair value hierarchy.
	(B)  Derivatives – Energy Related Assets and Liabilities are traded in both exchange-based and non-exchange-based markets. Exchange-based contracts are valued using unadjusted quoted market sources in active markets and are categorized in Level 1 in the fair value hierarchy. Certain non-exchange-based contracts are valued using indicative price quotations available through brokers or over-the-counter, on-line exchanges and are categorized in Level 2. These price quotations reflect the average of the bid-ask mid-point prices and are obtained from sources that management believes provide the most liquid market. Management reviews and corroborates the price quotations to ensure the prices are observable which includes consideration of actual transaction volumes, market delivery points, bid-ask spreads and contract duration.
	(C)  Derivatives – Other, include interest rate swaps that are valued using quoted prices on commonly quoted intervals, which are interpolated for periods different than the quoted intervals, as inputs to a market valuation model.  Market inputs can generally be verified and model selection does not involve significant management judgment.

STOCKBASED_COMPENSATION_PLANS_

STOCK-BASED COMPENSATION PLANS (Tables)	3 Months Ended
	Mar. 31, 2015
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Summary of the SJI nonvested restricted stock awards pertaining to SJG outstanding at and the assumptions used to estimate the fair value of the awards	The following table summarizes the SJI nonvested restricted stock awards pertaining to SJG outstanding at March 31, 2015, and the assumptions used to estimate the fair value of the awards:
	Grant Date		Shares		Fair Value		Expected		Risk-Free
			Outstanding		Per Share		Volatility		Interest Rate
	Jan. 2013 - TSR		8,002		$	22.19	21.1	%	0.4	%
	Jan. 2013 - EPS		8,002		$	25.59	n/a		n/a
	Jan. 2014 - TSR		10,394		$	21.31	20	%	0.8	%
	Jan. 2014 - EPS		10,394		$	27.22	n/a		n/a
	Jan. 2015 - TSR		6,874		$	26.31	16	%	1.1	%
	Jan. 2015 - EPS, ROE, Time		17,686		$	29.47	n/a		n/a
Summary of the information regarding restricted stock award activity excluding accrued dividend equivalents	The following table summarizes information regarding restricted stock award activity during the three months ended March 31, 2015, excluding accrued dividend equivalents:
		Shares		Weighted
				Average
				Grant Date
				Fair Value
	Nonvested Shares Outstanding, January 1, 2015	36,794		$	24.1
	Granted	24,560		$	28.58
	Nonvested Shares Outstanding, March 31, 2015	61,354		$	25.9

REGULATORY_ASSETS_AND_LIABILIT1

REGULATORY ASSETS AND LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Regulatory Assets and Liabilities Disclosure [Abstract]
Schedule of Regulatory Assets	Regulatory Assets consisted of the following items (in thousands):
		March 31, 2015		December 31, 2014
	Environmental Remediation Costs:
	Expended - Net	$	28,057	$	29,540
	Liability for Future Expenditures	124,761		124,308
	Deferred Asset Retirement Obligation Costs	31,604		31,584
	Deferred Pension and Other Postretirement Benefit Costs	99,040		99,040
	Deferred Gas Costs - Net	20,291		32,202
	Societal Benefit Costs Receivable	—		385
	Deferred Interest Rate Contracts (Note 11)	8,330		7,325
	Energy Efficiency Tracker	1,782		11,247
	Pipeline Supplier Service Charges	5,025		5,441
	Pipeline Integrity Cost	3,439		3,431
	AFUDC - Equity Related Deferrals	10,987		10,781
	Other Regulatory Assets	1,693		1,876
	Total Regulatory Assets	$	335,009	$	357,160
Schedule of Regulatory Liabilities	Regulatory Liabilities consisted of the following items (in thousands):
		March 31, 2015		December 31, 2014
	Excess Plant Removal Costs	$	35,762	$	35,940
	Conservation Incentive Program Payable	21,825		4,700
	Societal Benefit Costs	8,939		—
	Other Regulatory Liabilities	—		1,259
	Total Regulatory Liabilities	$	66,526	$	41,899

RELATEDPARTY_TRANSACTIONS_Tabl

RELATED-PARTY TRANSACTIONS (Tables)	3 Months Ended
	Mar. 31, 2015
Related Party Transactions [Abstract]
Summary of related party transactions	A summary of related party transactions, excluding pass-through items, included in Operating Revenues were as follows (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Operating Revenues/Affiliates:
	SJRG	$	1,052		$	158
	Marina	232			333
	Total Operating Revenue/Affiliates	$	1,284		$	491
	Related-party transactions, excluding pass-through items, included in Operating Expenses were as follows (in thousands):
		Three Months Ended
		March 31,
		2015			2014
	Costs of Sales/Affiliates (Excluding depreciation)
	SJRG	$	19,023		$	5,484
	Energy-Related Derivative (Gains) / Losses *
	SJRG	$	(4	)	$	(1,030	)
	* Contracts used to hedge natural gas purchases. Included in Cost of Sales on the Condensed Statement of Income.
	Operations Expense/Affiliates
	SJI	$	3,917		$	4,030
	Millennium	660			608
	Other	(109		)	(104		)
	Total Operations Expense/Affiliates	$	4,468		$	4,534

LINES_OF_CREDIT_Tables

LINES OF CREDIT (Tables)	3 Months Ended
	Mar. 31, 2015
Line of Credit Facility [Abstract]
Schedule of lines of credit	Credit facilities and available liquidity as of March 31, 2015 were as follows (in thousands):
		Total Facility		Usage		Available Liquidity		Expiration Date
	Commercial Paper Program/ Revolving Credit Facility	$	200,000	$	129,600	$	70,400	May-18
	Uncommitted Bank Lines	10,000		—		10,000		Various
	Total	$	210,000	$	129,600	$	80,400

PENSION_AND_OTHER_POSTRETIREME1

PENSION AND OTHER POSTRETIREMENT BENEFITS (Tables)	3 Months Ended
	Mar. 31, 2015
Compensation and Retirement Disclosure [Abstract]
Schedule of defined benefit plans disclosures	For the three months ended  March 31, 2015 and 2014, net periodic benefit cost related to the employee and officer pension and other postretirement benefit plans consisted of the following components (in thousands):
		Pension Benefits
		Three Months Ended
		March 31,
		2015			2014
	Service Cost	$	1,067		$	966
	Interest Cost	2,048			2,027
	Expected Return on Plan Assets	(2,734		)	(2,455		)
	Amortizations:
	Prior Service Cost	39			33
	Actuarial Loss	1,963			1,072
	Net Periodic Benefit Cost	2,383			1,643
	Capitalized Benefit Costs	(1,239		)	(854		)
	Total Net Periodic Benefit Expense	$	1,144		$	789
		Other Postretirement Benefits
		Three Months Ended
		March 31,
		2015			2014
	Service Cost	$	182		$	172
	Interest Cost	429			510
	Expected Return on Plan Assets	(416		)	(473		)
	Amortizations:
	Prior Service Cost	85			26
	Actuarial Loss	214			167
	Net Periodic Benefit Cost	494			402
	Capitalized Benefit Costs	(257		)	(209		)
	Total Net Periodic Benefit Expense	$	237		$	193

FAIR_VALUE_OF_FINANCIAL_ASSETS1

FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES (Tables)	3 Months Ended
	Mar. 31, 2015
Fair Value Disclosures [Abstract]
Fair value of assets and liabilities	For financial assets and financial liabilities measured at fair value on a recurring basis, information about the fair value measurements for each major category is as follows (in thousands):
	As of March 31, 2015
		Total		Level 1		Level 2		Level 3
	Assets
	Available-for-Sale Securities (A)	$	9,048	$	3,619	$	5,429	$	—
	Derivatives – Energy Related Assets (B)	1		1		—		—
		$	9,049	$	3,620	$	5,429	$	—
	Liabilities
	Derivatives – Energy Related Liabilities (B)	$	6,797	$	6,506	$	291	$	—
	Derivatives – Other (C)	8,330		—		8,330		—
		$	15,127	$	6,506	$	8,621	$	—
	As of December 31, 2014
		Total		Level 1		Level 2		Level 3
	Assets
	Available-for-Sale Securities (A)	$	8,894	$	5,924	$	2,970	$	—
	Derivatives - Energy Related Assets (B)	2,051		2		2,049		—
		$	10,945	$	5,926	$	5,019	$	—
	Liabilities
	Derivatives - Energy Related Liabilities (B)	$	7,603	$	7,254	$	349	$	—
	Derivatives - Other (C)	7,325		—		7,325		—
		$	14,928	$	7,254	$	7,674	$	—
	(A)  Available-for-Sale Securities include securities that are traded in active markets and securities that are not traded publicly.  The securities traded in active markets are valued using the quoted principal market close prices that are provided by the trustees and are categorized in Level 1 in the fair value hierarchy. The remaining securities consist of funds that are not publicly traded. These funds, which consist of stocks and bonds that are traded individually in active markets, are valued using quoted prices for similar assets and are categorized in Level 2 in the fair value hierarchy.
	(B)  Derivatives – Energy Related Assets and Liabilities are traded in both exchange-based and non-exchange-based markets. Exchange-based contracts are valued using unadjusted quoted market sources in active markets and are categorized in Level 1 in the fair value hierarchy. Certain non-exchange-based contracts are valued using indicative price quotations available through brokers or over-the-counter, on-line exchanges and are categorized in Level 2. These price quotations reflect the average of the bid-ask mid-point prices and are obtained from sources that management believes provide the most liquid market. Management reviews and corroborates the price quotations to ensure the prices are observable which includes consideration of actual transaction volumes, market delivery points, bid-ask spreads and contract duration.
	(C)  Derivatives – Other, include interest rate swaps that are valued using quoted prices on commonly quoted intervals, which are interpolated for periods different than the quoted intervals, as inputs to a market valuation model.  Market inputs can generally be verified and model selection does not involve significant management judgment.

DERIVATIVE_INSTRUMENTS_Tables

DERIVATIVE INSTRUMENTS (Tables)	3 Months Ended
	Mar. 31, 2015
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Fair value of derivative instruments	The fair values of all derivative instruments, as reflected in the condensed balance sheets as of March 31, 2015 and December 31, 2014, are as follows (in thousands):
	Derivatives not designated as hedging instruments under GAAP	March 31, 2015						December 31, 2014
		Assets			Liabilities			Assets			Liabilities
	Energy related commodity contracts:
	Derivatives – Energy Related – Current	$	1		$	5,781		$	2,051		$	6,305
	Derivatives – Energy Related – Non-Current	—			1,016			—			1,298
	Interest rate contracts:
	Derivatives – Other	—			8,330			—			7,325
	Total derivatives not designated as hedging instruments under GAAP	1			15,127			2,051			14,928
	Total Derivatives	$	1		$	15,127		$	2,051		$	14,928
Offsetting assets and liabilities	For derivative instruments disclosed in the table above, information as to the presentation on the condensed balance sheets is as follows (in thousands):
	As of March 31, 2015:
	Description	Gross amounts of recognized assets/liabilities			Gross amount offset in the balance sheet			Net amounts of assets/liabilities in balance sheet			Gross amounts not offset in the balance sheet						Net amount
											Financial Instruments				Cash Collateral Posted
	Derivatives - Energy Related Assets	$	1		$	—		$	1		$	(1	)	(A)	$	—	$	—
	Derivatives - Energy Related Liabilities	(6,797		)	—			(6,797		)	1			(B)	6,506		(290		)
	Derivatives - Other	(8,330		)	—			(8,330		)	—				—		(8,330		)
	As of December 31, 2014:
	Description	Gross amounts of recognized assets/liabilities			Gross amount offset in the balance sheet			Net amounts of assets/liabilities in balance sheet			Gross amounts not offset in the balance sheet						Net amount
											Financial Instruments				Cash Collateral Posted
	Derivatives - Energy Related Assets	$	2,051		$	—		$	2,051		$	(2	)	(A)	$	—	$	2,049
	Derivatives - Energy Related Liabilities	(7,603		)	—			(7,603		)	2			(B)	7,253		(348		)
	Derivatives - Other	(7,325		)	—			(7,325		)	—				—		(7,325		)
	(A) The balances at March 31, 2015 and December 31, 2014 were related to derivative liabilities which can be net settled against derivative assets.
	(B) The balances at March 31, 2015 and December 31, 2014 were related to derivative assets which can be net settled against derivative liabilities.
Derivatives in cash flow hedging relationships	The effect of derivative instruments on the condensed statements of income for the three months ended March 31, 2015 and 2014 are as follows (in thousands):
		Three months ended
		March 31,
	Derivatives in Cash Flow Hedging Relationships	2015			2014
	Interest Rate Contracts:
	Losses reclassified from Accumulated Other Comprehensive Loss into income (a)	$	(12	)	$	(12	)
	(a) Included in Interest Charges

ACCUMULATED_OTHER_COMPREHENSIV1

ACCUMULATED OTHER COMPREHENSIVE LOSS (Tables)	3 Months Ended
	Mar. 31, 2015
Equity [Abstract]
Schedule of changes in accumulated other comprehensive loss (AOCL)	The changes in Accumulated Other Comprehensive Loss (AOCL) for the three months ended March 31, 2015 are as follows (in thousands):
		Postretirement Liability Adjustment			Unrealized Gain (Loss) on Derivatives-Other			Unrealized Gain (Loss) on Available-for-Sale Securities			Total
	Balance at January 1, 2015 (a)	$	(13,837	)	$	(567	)	$	(75	)	$	(14,479	)
	Other comprehensive income before reclassifications	—			—			92			92
	Amounts reclassified from AOCL (b)	—			2			(38		)	(36		)
	Net current period other comprehensive income	—			2			54			56
	Balance at March 31, 2015 (a)	$	(13,837	)	$	(565	)	$	(21	)	$	(14,423	)
	(a) Determined using a combined average statutory tax rate of 40%.
	(b) See table below.
Reclassifications out of AOCL	The reclassifications out of AOCL during the three months ended March 31, 2015 are as follows (in thousands):
	Components of AOCL	Amounts Reclassified from AOCL (in thousands)			Affected Line Item in the Condensed Statements of Income
		Three Months Ended
		31-Mar-15
	Unrealized Loss in on Derivatives-Other - Interest Rate Contracts designated as cash flow hedges	$	12		Interest Charges
	Unrealized Gain on Available-for-Sale Securities	(64		)	Other Income & Expense
		(52		)	Income Before Income Taxes
	Income Taxes (a)	16			Income Taxes
	Gains from reclassifications for the period net of tax	$	(36	)
	(a) Determined using a combined average statutory tax rate of 40%.

SUMMARY_OF_SIGNIFICANT_ACCOUNT2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	3 Months Ended
In Millions, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014
Accounting Policies [Abstract]
Amount of Transitional Energy Facility Assessment and Public Utilities Assessment included in revenues and cost of sales	$0.60	$0.40

STOCKBASED_COMPENSATION_PLANS_1

STOCK-BASED COMPENSATION PLANS (Details) (USD $)	3 Months Ended		12 Months Ended	1 Months Ended
In Millions, except Share data, unless otherwise specified	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014	Jan. 31, 2015
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period of shares	3 years	3 years
Granted (in shares)	24,560
Shares Outstanding (in shares)	61,354		36,794
Fair Value Per Share (in dollars per share)	$25.90		$24.10
Expected volatility, measurement period	3 years
Service period of shares	3 years
Cost of Restricted Stock Awards	$0.10	$0.10
Restricted stock awards percentage capitalized	50.00%
Unrecognized compensation cost of awards granted under the plan	1
Weighted average period over which unrecognized compensation cost is to be recognized (in years)	2 years 2 months 12 days
Shares [Roll Forward]
Nonvested Shares Outstanding, beginning balance (in shares)	36,794			36,794
Granted (in shares)	24,560
Nonvested Shares Outstanding, ending balance (in shares)	61,354		36,794
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, beginning balance (in dollars per share)	$24.10			24.1
Weighted Average Grant Date Fair Value, Granted (in dollars per share)	$28.58
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$25.90		$24.10
Number of shares awarded during the period	0		0
Cash payments to SJI relating to stock awards	$0.20	$0.40
Grant Date January 2013 - TSR
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	8,002
Fair Value Per Share (in dollars per share)	$22.19
Expected Volatility	21.10%
Risk-Free Interest Rate	0.40%
Shares [Roll Forward]
Nonvested Shares Outstanding, ending balance (in shares)	8,002
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$22.19
Grant Date January 2013 - EPS
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	8,002
Fair Value Per Share (in dollars per share)	$25.59
Shares [Roll Forward]
Nonvested Shares Outstanding, ending balance (in shares)	8,002
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$25.59
Grant Date January 2014 - TSR
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	10,394
Fair Value Per Share (in dollars per share)	$21.31
Expected Volatility	20.00%
Risk-Free Interest Rate	0.80%
Shares [Roll Forward]
Nonvested Shares Outstanding, ending balance (in shares)	10,394
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$21.31
Grant Date January 2014 - EPS
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	10,394
Fair Value Per Share (in dollars per share)	$27.22
Shares [Roll Forward]
Nonvested Shares Outstanding, ending balance (in shares)	10,394
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$27.22
Grant Date January 2015 - TSR
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	6,874
Fair Value Per Share (in dollars per share)	$26.31
Expected Volatility	16.00%
Risk-Free Interest Rate	1.10%
Shares [Roll Forward]
Nonvested Shares Outstanding, ending balance (in shares)	6,874
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$26.31
Grant Date January 2015 - EPS, ROE, Time
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	17,686
Fair Value Per Share (in dollars per share)	$29.47
Shares [Roll Forward]
Nonvested Shares Outstanding, ending balance (in shares)	17,686
Weighted Average Grant Date Fair Value [Roll Forward]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$29.47
Restricted Stock
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Vesting period of shares	3 years
Share-based Compensation Arrangement by Share-based Payment Award, Payout Limit, Percentage	100.00%
Granted (in shares)				7,366
Shares [Roll Forward]
Granted (in shares)				7,366
Minimum
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Percentage of actual amount of shares that ultimately vest of original share units granted	0.00%
Maximum
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Percentage of actual amount of shares that ultimately vest of original share units granted	200.00%

RATES_AND_REGULATORY_ACTIONS_D

RATES AND REGULATORY ACTIONS (Details) (USD $)	0 Months Ended
In Millions, unless otherwise specified	Oct. 01, 2014	Sep. 30, 2014	Jan. 31, 2015
Schedule of Capitalization [Line Items]
Public utilities, approved base rate increase	$20
Public utilities, rate of return on base rate	7.10%
Public utilities, return on common equity	9.75%
Depreciate rate	2.10%	2.40%
Accelerated Infrastructure Replacement Program
Schedule of Capitalization [Line Items]
Public utilities, approved base rate increase	7.5
Energy Efficiency Tracker
Schedule of Capitalization [Line Items]
Amount of regulatory costs approved, statewide			$56

REGULATORY_ASSETS_AND_LIABILIT2

REGULATORY ASSETS AND LIABILITIES (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Regulatory Assets [Line Items]
Total Regulatory Assets	$335,009	$357,160
Environmental Remediation Costs: Expended - Net
Regulatory Assets [Line Items]
Total Regulatory Assets	28,057	29,540
Environmental Remediation Costs: Liability for Future Expenditures
Regulatory Assets [Line Items]
Total Regulatory Assets	124,761	124,308
Deferred Asset Retirement Obligation Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	31,604	31,584
Deferred Pension and Other Postretirement Benefit Costs
Regulatory Assets [Line Items]
Total Regulatory Assets	99,040	99,040
Deferred Gas Costs - Net
Regulatory Assets [Line Items]
Total Regulatory Assets	20,291	32,202
Societal Benefit Costs Receivable
Regulatory Assets [Line Items]
Total Regulatory Assets	0	385
Deferred Interest Rate Contracts
Regulatory Assets [Line Items]
Total Regulatory Assets	8,330	7,325
Energy Efficiency Tracker
Regulatory Assets [Line Items]
Total Regulatory Assets	1,782	11,247
Pipeline Supplier Service Charges
Regulatory Assets [Line Items]
Total Regulatory Assets	5,025	5,441
Pipeline Integrity Cost
Regulatory Assets [Line Items]
Total Regulatory Assets	3,439	3,431
AFUDC - Equity Related Deferrals
Regulatory Assets [Line Items]
Total Regulatory Assets	10,987	10,781
Other Regulatory Assets
Regulatory Assets [Line Items]
Total Regulatory Assets	$1,693	$1,876

REGULATORY_ASSETS_AND_LIABILIT3

REGULATORY ASSETS AND LIABILITIES 2 (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	$66,526	$41,899
Excess Plant Removal Costs
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	35,762	35,940
Conservation Incentive Program Payable
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	21,825	4,700
Societal Benefit Costs
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	8,939	0
Other Regulatory Liabilities
Regulatory Liabilities [Line Items]
Total Regulatory Liabilities	$0	$1,259

RELATEDPARTY_TRANSACTIONS_Deta

RELATED-PARTY TRANSACTIONS (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Related Party Transaction [Line Items]
Operating Revenues/Affiliates	$1,284		$491
Operations Expense/Affiliates	4,468		4,534
SJRG
Related Party Transaction [Line Items]
Operating Revenues/Affiliates	1,052		158
Costs of Sales/Affiliates (Excluding depreciation)	19,023		5,484
Energy-Related Derivative (Gains) / Losses	-4	[1]	-1,030	[1]
Marina
Related Party Transaction [Line Items]
Operating Revenues/Affiliates	232		333
SJI
Related Party Transaction [Line Items]
Operations Expense/Affiliates	3,917		4,030
Millennium
Related Party Transaction [Line Items]
Operations Expense/Affiliates	660		608
Other
Related Party Transaction [Line Items]
Operations Expense/Affiliates	($109)		($104)
[1]	Contracts used to hedge natural gas purchases. Included in Cost of Sales on the Condensed Statement of Income.

FINANCIAL_INSTRUMENTS_Details

FINANCIAL INSTRUMENTS (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Millions, unless otherwise specified
Schedule of Financial Instruments [Line Items]
Restricted investments held in escrow	$0.10	$0.10
Restricted investments, energy-related contracts	8.8	7.8
Estimated fair value of long-term debt	595.8	587.3
Carrying amount of long-term debt	543	543
Financing Receivable
Schedule of Financial Instruments [Line Items]
Long-term receivables, net of unamortized discount	14.9	15
Imputed interest	$1.20	$1.30

LINES_OF_CREDIT_Details

LINES OF CREDIT (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014
Line of Credit Facility [Line Items]
Total Facility	$210,000,000
Usage	129,600,000
Available Liquidity	80,400,000
Average borrowings outstanding during the period	108,500,000	40,800,000
Maximum amounts outstanding during the period	136,900,000	66,000,000
Weighted average borrowing cost	0.50%	0.25%
Minimum
Line of Credit Facility [Line Items]
Financial covenant, ratio of indebtedness to consolidated total capitalization minimum	0.65
Revolving Credit Facility
Line of Credit Facility [Line Items]
Total Facility	200,000,000
Usage	129,600,000
Available Liquidity	70,400,000
Expiration Date	May-18
Uncommitted Bank Lines
Line of Credit Facility [Line Items]
Total Facility	10,000,000
Usage	0
Available Liquidity	10,000,000
Expiration Date	Various
South Jersey Gas Commercial Paper Program
Line of Credit Facility [Line Items]
Total Facility	$200,000,000
Fixed maturities of notes, at maximum number of days (in days)	270 days

PENSION_AND_OTHER_POSTRETIREME2

PENSION AND OTHER POSTRETIREMENT BENEFITS (Details) (USD $)	1 Months Ended	3 Months Ended		12 Months Ended
	Jan. 31, 2015	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Pension Benefits
Net periodic benefit cost
Service Cost		$1,067,000	$966,000
Interest Cost		2,048,000	2,027,000
Expected Return on Plan Assets		-2,734,000	-2,455,000
Amortizations:
Prior Service Cost		39,000	33,000
Actuarial Loss		1,963,000	1,072,000
Net Periodic Benefit Cost		2,383,000	1,643,000
Capitalized Benefit Costs		-1,239,000	-854,000
Total Net Periodic Benefit Expense		1,144,000	789,000
Contributions	12,000,000			0
Other Postretirement Benefits
Net periodic benefit cost
Service Cost		182,000	172,000
Interest Cost		429,000	510,000
Expected Return on Plan Assets		-416,000	-473,000
Amortizations:
Prior Service Cost		85,000	26,000
Actuarial Loss		214,000	167,000
Net Periodic Benefit Cost		494,000	402,000
Capitalized Benefit Costs		-257,000	-209,000
Total Net Periodic Benefit Expense		237,000	193,000
Defined benefit plan regulatory obligation to contribute to the plan during the period		3,600,000
Supplemental Employee Retirement Plans, Defined Benefit
Amortizations:
Estimated future contributions		$1,500,000

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Dec. 31, 2014
	unions	sites
	sites
Loss Contingencies [Line Items]
Letter of credit provided	$210,000,000
Number of sites for environmental cleanup		12
Monthly gas supply related demand charges and reservation fees	3,900,000
Estimated litigation liability	800,000	500,000
Percentage of personnel represented in collective bargaining agreements	60.00%
Number of unions	2
Standby Letter of Credit
Loss Contingencies [Line Items]
Letter of credit provided	$25,200,000

FAIR_VALUE_OF_FINANCIAL_ASSETS2

FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES (Details) (Fair Value, Measurements, Recurring, USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Assets
Available-for-sale Securities	$9,048	[1]	$8,894	[1]
Derivatives - Energy Related Assets	1	[2]	2,051	[2]
Total Assets	9,049		10,945
Liabilities
Derivatives - Energy Related Liabilities	6,797	[2]	7,603	[2]
Derivatives - Other	8,330	[3]	7,325	[3]
Total Liabilities	15,127		14,928
Level 1
Assets
Available-for-sale Securities	3,619	[1]	5,924	[1]
Derivatives - Energy Related Assets	1	[2]	2	[2]
Total Assets	3,620		5,926
Liabilities
Derivatives - Energy Related Liabilities	6,506	[2]	7,254	[2]
Derivatives - Other	0	[3]	0	[3]
Total Liabilities	6,506		7,254
Level 2
Assets
Available-for-sale Securities	5,429	[1]	2,970	[1]
Derivatives - Energy Related Assets	0	[2]	2,049	[2]
Total Assets	5,429		5,019
Liabilities
Derivatives - Energy Related Liabilities	291	[2]	349	[2]
Derivatives - Other	8,330	[3]	7,325	[3]
Total Liabilities	8,621		7,674
Level 3
Assets
Available-for-sale Securities	0	[1]	0	[1]
Derivatives - Energy Related Assets	0	[2]	0	[2]
Total Assets	0		0
Liabilities
Derivatives - Energy Related Liabilities	0	[2]	0	[2]
Derivatives - Other	0	[3]	0	[3]
Total Liabilities	$0		$0
[1]	Available-for-Sale Securities include securities that are traded in active markets and securities that are not traded publicly. The securities traded in active markets are valued using the quoted principal market close prices that are provided by the trustees and are categorized in Level 1 in the fair value hierarchy. The remaining securities consist of funds that are not publicly traded. These funds, which consist of stocks and bonds that are traded individually in active markets, are valued using quoted prices for similar assets and are categorized in Level 2 in the fair value hierarchy.
[2]	Derivatives b Energy Related Assets and Liabilities are traded in both exchange-based and non-exchange-based markets. Exchange-based contracts are valued using unadjusted quoted market sources in active markets and are categorized in Level 1 in the fair value hierarchy. Certain non-exchange-based contracts are valued using indicative price quotations available through brokers or over-the-counter, on-line exchanges and are categorized in Level 2. These price quotations reflect the average of the bid-ask mid-point prices and are obtained from sources that management believes provide the most liquid market. Management reviews and corroborates the price quotations to ensure the prices are observable which includes consideration of actual transaction volumes, market delivery points, bid-ask spreads and contract duration.
[3]	Derivatives b Other, include interest rate swaps that are valued using quoted prices on commonly quoted intervals, which are interpolated for periods different than the quoted intervals, as inputs to a market valuation model. Market inputs can generally be verified and model selection does not involve significant management judgment.

DERIVATIVE_INSTRUMENTS_Details

DERIVATIVE INSTRUMENTS (Details) (USD $)	1 Months Ended
In Millions, unless otherwise specified	Sep. 30, 2005	Mar. 31, 2015	Dec. 31, 2014
Derivative [Line Items]
Unrealized gains (losses) included in its BGSS related to open financial contracts		($6.80)	($5.60)
Initial cost of Treasury Locks	1.4
Amortization period of Treasury Locks (in years)	30 years
Unamortized balance of Treasury Locks		$0.90	$1
Basis and Index Related Purchase and Sales Contracts
Derivative [Line Items]
Outstanding derivative contracts notional amount (MMdts)		800,000
Natural Gas (in MMdts) | Derivative Transaction Type, Purchase
Derivative [Line Items]
Outstanding derivative contracts notional amount (MMdts)		11,600,000
Natural Gas (in MMdts) | Derivative Transaction Type, Sale
Derivative [Line Items]
Outstanding derivative contracts notional amount (MMdts)		40,000

DERIVATIVE_INSTRUMENTS_2_Detai

DERIVATIVE INSTRUMENTS 2 (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	$1	$2,051
Fair value Derivative Liabilities	15,127	14,928
Not Designated as Hedging Instrument
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	1	2,051
Fair value Derivative Liabilities	15,127	14,928
Commodity Contract | Not Designated as Hedging Instrument | Derivatives-Energy Related-Current
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	1	2,051
Fair value Derivative Liabilities	5,781	6,305
Commodity Contract | Not Designated as Hedging Instrument | Derivatives-Energy Related-NonCurrent
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	0	0
Fair value Derivative Liabilities	1,016	1,298
Interest Rate Contract | Not Designated as Hedging Instrument | Derivatives-Other
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	0	0
Fair value Derivative Liabilities	$8,330	$7,325

DERIVATIVE_INSTRUMENTS_3_Detai

DERIVATIVE INSTRUMENTS 3 (Details) (USD $)	Mar. 31, 2015		Dec. 31, 2014
In Thousands, unless otherwise specified
Commodity Contract
Offsetting Derivative Assets [Abstract]
Gross amounts of recognized assets/liabilities	$1		$2,051
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	1		2,051
Gross amounts not offset in the balance sheet, Financial Instruments	-1	[1]	-2	[1]
Gross amounts not offset in the balance sheet, Cash Collateral Posted	0		0
Net amount	0		2,049
Offsetting Derivative Liabilities [Abstract]
Gross amounts of recognized assets/liabilities	-6,797		-7,603
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	-6,797		-7,603
Gross amounts not offset in the balance sheet, Financial Instruments	1	[2]	2	[2]
Gross amounts not offset in the balance sheet, Cash Collateral Posted	6,506		7,253
Net amount	-290		-348
Interest Rate Contract
Offsetting Derivative Liabilities [Abstract]
Gross amounts of recognized assets/liabilities	-8,330		-7,325
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	-8,330		-7,325
Gross amounts not offset in the balance sheet, Financial Instruments	0		0
Gross amounts not offset in the balance sheet, Cash Collateral Posted	0		0
Net amount	($8,330)		($7,325)
[1]	The balances at March 31, 2015 and December 31, 2014 were related to derivative liabilities which can be net settled against derivative assets.
[2]	The balances at March 31, 2015 and December 31, 2014 were related to derivative assets which can be net settled against derivative liabilities.

DERIVATIVE_INSTRUMENTS_4_Detai

DERIVATIVE INSTRUMENTS 4 (Details) (USD $)	3 Months Ended
	Mar. 31, 2015		Mar. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Losses reclassified from Accumulated Other Comprehensive Loss into income	($12,000)	[1]	($12,000)	[1]
Net Realized gains (losses), derivative instruments, energy-related contracts	($2,600,000)		$2,400,000
[1]	Included in Interest Charges

ACCUMULATED_OTHER_COMPREHENSIV2

ACCUMULATED OTHER COMPREHENSIVE LOSS (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	($14,479)	[1]
Other comprehensive income before reclassifications	92
Amounts reclassified from AOCL	-36	[2]
Other Comprehensive Gain - Net of Tax	56	[3]	70	[3]
Ending balance	-14,423	[1]
Combined statutory tax rate	40.00%		41.00%
Postretirement Liability Adjustment
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	-13,837	[1]
Other comprehensive income before reclassifications	0
Amounts reclassified from AOCL	0	[2]
Other Comprehensive Gain - Net of Tax	0
Ending balance	-13,837	[1]
Unrealized Gain (Loss) on Derivatives-Other
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	-567	[1]
Other comprehensive income before reclassifications	0
Amounts reclassified from AOCL	2	[2]
Other Comprehensive Gain - Net of Tax	2
Ending balance	-565	[1]
Unrealized Gain (Loss) on Available-for-Sale Securities
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	-75	[1]
Other comprehensive income before reclassifications	92
Amounts reclassified from AOCL	-38	[2]
Other Comprehensive Gain - Net of Tax	54
Ending balance	($21)	[1]
[1]	Determined using a combined average statutory tax rate of 40%.
[2]	See table below.
[3]	Determined using a combined average statutory tax rate of 40% and 41% in 2015 and 2014, respectively.

ACCUMULATED_OTHER_COMPREHENSIV3

ACCUMULATED OTHER COMPREHENSIVE LOSS 2 (Details) (USD $)	3 Months Ended
In Thousands, unless otherwise specified	Mar. 31, 2015		Mar. 31, 2014
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest Charges	$5,190		$4,342
Other Income and Expense	-760		-1,086
Income Before Income Taxes	-68,759		-60,184
Income Taxes	26,172		22,527
Net Income	-42,587		-37,657
Reclassification out of Accumulated Other Comprehensive Income
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income Before Income Taxes	-52
Income Taxes	16	[1]
Net Income	-36
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Loss in on Derivatives-Other - Interest Rate Contracts designated as cash flow hedges
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest Charges	12
Reclassification out of Accumulated Other Comprehensive Income | Unrealized Gain on Available-for-Sale Securities
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Other Income and Expense	($64)
[1]	Determined using a combined average statutory tax rate of 40%.

SUBSEQUENT_EVENTS_Details

SUBSEQUENT EVENTS (Details) (Subsequent Event, USD $)	Apr. 01, 2015
In Thousands, unless otherwise specified
Subsequent Event
Subsequent Event [Line Items]
Dividends Payable	$9,891