SOUTH JERSEY GAS 10-K 27 Feb 15 2014 FY Annual report Financial data

DOCUMENT_AND_ENTITY_INFORMATIO

DOCUMENT AND ENTITY INFORMATION (USD $)	12 Months Ended
	Dec. 31, 2014	Feb. 15, 2015	Jun. 30, 2014
Entity [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-K
Document Period End Date	31-Dec-14
Document Fiscal Year Focus	2014
Document Fiscal Period Focus	FY
Amendment Flag	FALSE
Entity Common Stock, Shares Outstanding		2,339,139
Entity Well-known Seasoned Issuer	No
Entity Voluntary Filers	No
Entity Current Reporting Status	Yes
Entity Public Float			$0

STATEMENTS_OF_INCOME

STATEMENTS OF INCOME (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Statement [Abstract]
Operating Revenues	$501,875	$446,480	$421,874
Operating Expenses:
Cost of Sales (Excluding depreciation)	231,216	200,081	188,710
Operations	102,428	85,805	78,425
Maintenance	13,457	13,135	13,615
Depreciation	37,324	33,775	31,062
Energy and Other Taxes	3,760	7,862	8,300
Total Operating Expenses	388,185	340,658	320,112
Operating Income	113,690	105,822	101,762
Other Income and Expense	5,560	3,797	2,617
Interest Charges	-17,872	-12,550	-12,427
Income Before Income Taxes	101,378	97,069	91,952
Income Taxes	-34,895	-34,833	-33,711
Net Income	$66,483	$62,236	$58,241

STATEMENTS_OF_COMPREHENSIVE_IN

STATEMENTS OF COMPREHENSIVE INCOME (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Statement of Comprehensive Income [Abstract]
Net Income	$66,483		$62,236		$58,241
Other Comprehensive Income (Loss), Net of Tax:
Postretirement Liability Adjustment	-3,165	[1]	2,286	[1]	-1,683	[1]
Unrealized (Loss) Gain on Available-for-Sale Securities	-472	[1]	103	[1]	500	[1]
Unrealized Gain on Derivatives - Other	27	[1]	27	[1]	27	[1]
Other Comprehensive (Loss) Income- Net of Tax	-3,610	[1]	2,416	[1]	-1,156	[1]
Comprehensive Income	$62,873		$64,652		$57,085
Combined statutory rate	40.00%		41.00%		41.00%
[1]	Determined using a combined statutory tax rate of 40% in 2014 and 41% in 2013 and 2012.

STATEMENTS_OF_CASH_FLOWS

STATEMENTS OF CASH FLOWS (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Net Cash Provided by (Used in) Operating Activities [Abstract]
Net Income	$66,483	$62,236	$58,241
Provided by Operating Activities:
Depreciation and Amortization	52,155	48,261	44,171
Provision for Losses on Accounts Receivable	9,417	4,232	4,775
CIP Receivable/Payable	15,226	21,160	-18,106
Deferred Gas Costs - Net of Recoveries	-44,976	5,473	25,050
Deferred SBC Costs - Net of Recoveries	11,048	2,393	-4,183
Environmental Remediation Costs - Net of Recoveries	-8,248	-438	-188
Deferred and Noncurrent Income Taxes and Credits - Net	32,193	31,940	38,353
Gas Plant Cost of Removal	-4,848	-6,092	-2,133
Pension Contribution	0	-9,100	-19,757
Changes in:
Accounts Receivable	-14,667	-20,574	-34,263
Inventories	-3,820	-7,153	13,449
Prepaid and Accrued Taxes - Net	-6,508	9,456	6,451
Other Prepayments and Current Assets	131	-476	430
Gas Purchases Payable	-1,873	9,306	-2,941
Accounts Payable and Other Accrued Liabilities	11,302	-5,107	-8,803
Other Assets	-7,481	-7,323	-10,980
Other Liabilities	-2,006	10,565	3,807
Net Cash Provided by Operating Activities	103,528	148,759	93,373
Cash Flows from Investing Activities:
Capital Expenditures	-200,008	-161,498	-156,041
Net (Investment in) Proceeds from Restricted Investments in Margin Account	-7,281	588	930
Investment in Long-Term Receivables	-13,024	-7,182	-6,243
Proceeds from Long-Term Receivables	6,544	5,764	8,182
Net Cash Used in Investing Activities	-213,769	-162,328	-153,172
Cash Flows from Financing Activities:
Net Borrowings from (Repayments of) Short-Term Credit Facilities	35,900	-36,600	-24,500
Proceeds from Issuance of Long-Term Debt	89,000	50,000	120,000
Principal Repayments of Long-Term Debt	-21,000	-25,000	-35,000
Premium for Early Retirement of Debt	0	0	-700
Payments for Issuance of Long-Term Debt	-627	-411	-951
Dividends on Common Stock	-18,201	0	0
Additional Investment by Shareholder	25,000	25,000	0
Excess (Tax Deficiency) Tax Benefit from Restricted Stock Plan	-73	-78	124
Net Cash Provided by Financing Activities	109,999	12,911	58,973
Net Decrease in Cash and Cash Equivalents	-242	-658	-826
Cash and Cash Equivalents at Beginning of Period	2,020	2,678	3,504
Cash and Cash Equivalents at End of Period	1,778	2,020	2,678
Supplemental Disclosures of Cash Flow Information
Interest (Net of Amounts Capitalized)	17,832	12,234	12,073
Income Taxes (Net of Refunds)	-7,690	-5,056	-2,797
Supplemental Disclosures of Noncash Investing Activities
Property and equipment acquired on account but not paid at year-end	$17,551	$20,055	$11,069

BALANCE_SHEETS

BALANCE SHEETS (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Property, Plant and Equipment:
Utility Plant, at original cost	$2,002,966		$1,816,804
Accumulated Depreciation	-413,597		-392,029
Property, Plant and Equipment - Net	1,589,369		1,424,775
Investments:
Available-for-Sale Securities	8,894		8,696
Restricted Investments	7,961		680
Total Investments	16,855		9,376
Current Assets:
Cash and Cash Equivalents	1,778		2,020
Accounts Receivable	60,535		60,317
Accounts Receivable - Related Parties	1,157		968
Unbilled Revenues	49,910		41,510
Provision for Uncollectibles	-6,601		-4,553
Natural Gas in Storage, average cost	25,325		20,811
Materials and Supplies, average cost	1,104		1,798
Deferred Income Taxes - Net	44,064		23,309
Prepaid Taxes	13,601		7,683
Derivatives - Energy Related Assets	2,051		1,222
Other Prepayments and Current Assets	3,688		3,819
Total Current Assets	196,612		158,904
Regulatory and Other Noncurrent Assets:
Regulatory Assets	357,160		296,081
Unamortized Debt Issuance Costs	7,382		6,523
Long-Term Receivables	15,223		10,252
Derivatives - Energy Related Assets	0		278
Other	3,071		2,937
Total Regulatory and Other Noncurrent Assets	382,836		316,071
Total Assets	2,185,672		1,909,126
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		225,972
Accumulated Other Comprehensive Loss	-14,479	[1]	-10,869	[1]
Retained Earnings	438,300		390,018
Total Common Equity	680,568		610,969
Long-Term Debt	507,091	[2]	454,000	[2]
Total Capitalization	1,187,659		1,064,969
Current Liabilities:
Notes Payable	101,400		65,500
Current Portion of Long-Term Debt	35,909	[2],[3]	21,000	[2],[3]
Accounts Payable - Commodity	22,359		24,232
Accounts Payable - Other	32,711		32,072
Accounts Payable - Related Parties	11,249		6,638
Derivatives - Energy Related Liabilities	6,305		711
Customer Deposits and Credit Balances	17,626		15,089
Environmental Remediation Costs	28,480		15,422
Taxes Accrued	1,177		1,767
Pension Benefits	1,515		1,241
Interest Accrued	6,099		6,039
Other Current Liabilities	6,580		5,629
Total Current Liabilities	271,410		195,340
Regulatory and Other Noncurrent Liabilities:
Regulatory Liabilities	41,899		60,949
Deferred Income Taxes - Net	435,022		380,975
Environmental Remediation Costs	95,828		104,070
Asset Retirement Obligations	41,976		41,178
Pension and Other Postretirement Benefits	95,241		48,197
Investment Tax Credits	149		360
Derivatives - Energy Related Liabilities	1,298		48
Derivatives - Other	7,325		3,735
Other	7,865		9,305
Total Regulatory and Other Noncurrent Liabilities	726,603		648,817
Commitments and Contingencies (Note 9)
Total Capitalization and Liabilities	$2,185,672		$1,909,126
[1]	Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.
[2]	Long-term debt maturities and sinking funds requirements for the succeeding five years are as follows (in thousands): 2015, $35,909; 2016, $27,909; 2017, $74,909; 2018, $38,909; 2019, $18,909.
[3]	These variable rate demand bonds bear interest at a floating rate that resets weekly. The interest rate as of December 31, 2014 was 0.08%. Liquidity support on these bonds is provided under a separate letter of credit facility that expires in August, 2015; as such, these bonds have been included in the current portion of long-term debt. These bonds contain no financial covenants.

BALANCE_SHEETS_Parenthetical

BALANCE SHEETS (Parenthetical) (USD $)	Dec. 31, 2014	Dec. 31, 2013
Statement of Financial Position [Abstract]
Common stock, par value (in dollars per share)	$2.50	$2.50
Common stock, shares authorized	4,000,000	4,000,000
Common stock, shares outstanding	2,339,139	2,339,139

STATEMENTS_OF_CHANGES_IN_COMMO

STATEMENTS OF CHANGES IN COMMON EQUITY AND COMPREHENSIVE INCOME (USD $)		Total	Common Stock [Member]	Other Paid-In Capital and Premium on Common Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Retained Earnings [Member]
In Thousands, unless otherwise specified
Balance at Dec. 31, 2011		$464,186	$5,848	$200,926	($12,129)	$269,541
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		58,241				58,241
Other Comprehensive (Loss) Gain, Net of Tax	[1]	-1,156			-1,156
Cash Dividends Declared – Common Stock		0				0
Additional Investment by Shareholder		0
Excess Tax Benefit (Tax Deficiency) from Restricted Stock Plan		124		124
Additional Statement Information [Abstract]
Combined statutory rate		41.00%
Balance at Dec. 31, 2012		521,395	5,848	201,050	-13,285	327,782
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		62,236				62,236
Other Comprehensive (Loss) Gain, Net of Tax	[1]	2,416			2,416
Cash Dividends Declared – Common Stock		0				0
Additional Investment by Shareholder		25,000		25,000
Excess Tax Benefit (Tax Deficiency) from Restricted Stock Plan		-78		-78
Additional Statement Information [Abstract]
Combined statutory rate		41.00%
Balance at Dec. 31, 2013		610,969	5,848	225,972	-10,869	390,018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		66,483				66,483
Other Comprehensive (Loss) Gain, Net of Tax	[1]	-3,610			-3,610
Cash Dividends Declared – Common Stock		-18,201				-18,201
Additional Investment by Shareholder		25,000		25,000
Excess Tax Benefit (Tax Deficiency) from Restricted Stock Plan		-73		-73
Additional Statement Information [Abstract]
Combined statutory rate		40.00%
Balance at Dec. 31, 2014		$680,568	$5,848	$250,899	($14,479)	$438,300
[1]	Determined using a combined statutory tax rate of 40% in 2014 and 41% in 2013 and 2012.

STATEMENTS_OF_CHANGES_IN_COMMO1

STATEMENTS OF CHANGES IN COMMON EQUITY AND COMPREHENSIVE INCOME (Parenthetical) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Change In Accumulated Other Comprehensive Loss Balances [Roll Forward]
Beginning balance	($10,869)	[1]	($13,285)	[1]
Changes During Year	-3,610	[2]	2,416	[2]	-1,156	[2]
Ending balance	-14,479	[1]	-10,869	[1]	-13,285	[1]
Postretirement Liability Adjustment [Member]
Change In Accumulated Other Comprehensive Loss Balances [Roll Forward]
Beginning balance	-10,672	[1],[2]	-12,958	[1],[2]	-11,275	[2]
Changes During Year	-3,165	[2]	2,286	[2]	-1,683	[2]
Ending balance	-13,837	[1],[2]	-10,672	[1],[2]	-12,958	[1],[2]
Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Change In Accumulated Other Comprehensive Loss Balances [Roll Forward]
Beginning balance	397	[1],[2]	294	[1],[2]	-206	[2]
Changes During Year	-472	[2]	103	[2]	500	[2]
Ending balance	-75	[1],[2]	397	[1],[2]	294	[1],[2]
Unrealized Gain (Loss) on Derivatives [Member]
Change In Accumulated Other Comprehensive Loss Balances [Roll Forward]
Beginning balance	-594	[1],[2]	-621	[1],[2]	-648	[2]
Changes During Year	27	[2]	27	[2]	27	[2]
Ending balance	-567	[1],[2]	-594	[1],[2]	-621	[1],[2]
Accumulated Other Comprehensive Income (Loss) [Member]
Change In Accumulated Other Comprehensive Loss Balances [Roll Forward]
Beginning balance	-10,869	[2]	-13,285	[2]	-12,129	[2]
Changes During Year	-3,610	[2]	2,416	[2]	-1,156	[2]
Ending balance	($14,479)	[2]	($10,869)	[2]	($13,285)	[2]
[1]	Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.
[2]	Determined using a combined statutory tax rate of 40% in 2014 and 41% in 2013 and 2012.

SUMMARY_OF_SIGNIFICANT_ACCOUNT

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES	12 Months Ended
	Dec. 31, 2014
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). In our opinion, the 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.
	Certain reclassifications have been made to the prior period's regulatory assets disclosure to conform to the current period presentation. The deferred pipeline integrity cost previously included in "Other Regulatory Assets" was reclassified to the line item "Pipeline Integrity Cost" in the regulatory asset table disclosed in Note 4.
	Equity Investments - Marketable equity securities that are purchased as long-term investments are classified as Available-for-Sale Securities and carried at their fair value on our balance sheets. Any unrealized gains or losses are included in Accumulated Other Comprehensive Loss.  An impairment loss is recorded when there is clear evidence that a decline in value is other than temporary.   No impairment losses were recorded on Investments during 2014, 2013 or 2012.
	Estimates and Assumptions - We prepare our financial statements to conform with accounting principles generally accepted in the United States of America (GAAP). Management makes estimates and assumptions that affect the amounts reported in the financial statements and related disclosures. Therefore, actual results could differ from those estimates. Significant estimates include amounts related to regulatory accounting, energy derivatives, environmental remediation costs, pension and other postretirement benefit costs, and revenue recognition.
	Regulation - We are subject to the rules and regulations of the New Jersey Board of Public Utilities (BPU). See Note 3 for a detailed discussion of our rate structure and regulatory actions. We maintain our accounts according to the BPU’s prescribed Uniform System of Accounts. We follow the accounting for regulated enterprises prescribed by the FASB ASC Topic 980 – “Regulated Operations.”  In general, Topic 980 allows for the deferral of certain costs (regulatory assets) and creation of certain obligations (regulatory liabilities) when it is probable that such items will be recovered from or refunded to customers in future periods. See Note 4 for a detailed discussion of regulatory assets and liabilities.
	Operating Revenues - Gas revenues are recognized in the period the commodity is delivered to customers. For retail customers that are not billed at the end of the month, we record an estimate to recognize unbilled revenues for gas delivered from the date of the last meter reading to the end of the month.
	Revenue and Throughput-Based Taxes - SJG collects certain revenue-based energy taxes from our 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 cost of sales and totaled $1.1 million, $1.2 million and $0.9 million in 2014, 2013 and 2012, respectively. In prior years, SJG had collected a throughput-based energy tax from customers in the form of a Transitional Energy Facility Assessment (TEFA ). The TEFA was included in both revenues and cost of sales and totaled $4.0 million, and $5.1 million in 2013 and 2012, respectively. The TEFA was eliminated effective January 1, 2014.
	Accounts Receivable and Provision for Uncollectible Accounts - Accounts receivable are carried at the amount owed by customers. A provision for uncollectible accounts is established based on our collection experience and an assessment of the collectibility of specific accounts.
	Natural Gas in Storage – Natural Gas in Storage is reflected at average cost on the balance sheets, and represents natural gas that will be utilized in the ordinary course of business.
	Property, Plant & Equipment - For regulatory purposes, utility plant is stated at original cost, which may be different than our cost if the assets were acquired from another regulated entity. The cost of adding, replacing and renewing property is charged to the appropriate plant account. Utility Plant balances as of December 31, 2014 and 2013 were comprised of the following (in thousands):
		2014			2013
	Utility Plant:
	Production Plant	$	296		$	296
	Storage Plant	23,023			22,538
	Transmission Plant	248,737			248,074
	Distribution Plant	1,547,218			1,417,939
	General Plant	103,604			53,162
	Other Plant	1,855			1,855
	Utility Plant in Service	1,924,733			1,743,864
	Construction Work in Progress	78,233			72,940
	Total Utility Plant	$	2,002,966		$	1,816,804
	The increase in Utility Plant in Service is related to projects for distribution, some of which are part of the Company's Accelerated Infrastructure Replacement Program (AIRP), as discussed under Note 3.
	Asset Retirement Obligations - The amounts included under Asset Retirement Obligations (ARO) are primarily related to the legal obligations we have to cut and cap our gas distribution pipelines when taking those pipelines out of service in future years. These liabilities are generally recognized upon the acquisition or construction of the asset. The related asset retirement cost is capitalized concurrently by increasing the carrying amount of the related asset by the same amount as the liability. Changes in the liability are recorded for the passage of time (accretion) or for revisions to cash flows originally estimated to settle the ARO.
	ARO activity during 2014 and 2013 was as follows (in thousands):
		2014			2013
	ARO as of January 1,	$	41,178		$	38,892
	Accretion	1,595			1,514
	Additions	664			743
	Settlements	(1,461		)	(1,630		)
	Revisions in Estimated Cash Flows *	—			1,659
	ARO as of December 31,	$	41,976		$	41,178
	* The revision in estimated cash flows in 2013 reflects an increase in the inflation rate used to determine the ARO settlement amount.
	Depreciation - We depreciate utility plant on a straight-line basis over the estimated remaining lives of the various property classes. These estimates are periodically reviewed and adjusted as required after BPU approval. The composite annual rate for all depreciable utility property was approximately 2.2% in 2014, 2.3% in 2013 and 2.4% in 2012. The actual composite rate may differ from the approved rate as the asset mix changes over time. Except for retirements outside of the normal course of business, accumulated depreciation is charged with the cost of depreciable utility property retired, less salvage. Effective October 1, 2014, SJG's composite depreciation rate was reduced from 2.4% to 2.1%. See Note 3.
	Capitalized Interest - We capitalize interest on construction at the rate of return on rate base utilized by the BPU to set rates in our last base rate proceeding (See Note 3). Capitalized interest is included in Utility Plant on the balance sheets. Interest Charges are presented net of capitalized interest on the statements of income.  We capitalized interest of $4.4 million in 2014, $8.2 million in 2013 and $6.5 million in 2012. The decrease in 2014 is related to the CIRT projects rolling into customer rates effective October 31, 2013 . Under the CIRT, qualified capital expenditures continued to accrue interest on construction until such projects were rolled into customer rates and recovery of the expenditures commenced.All CIRT program investments have been rolled into rate base and the CIRT program is now concluded. See Note 3 for additional discussion of the CIRT programs.
	Impairment of Long-Lived Assets - We review the carrying amount of long-lived assets for possible impairment whenever events or changes in circumstances indicate that such amounts may not be recoverable. For the years ended 2014, 2013 and 2012, no significant impairments were identified.
	Derivative Instruments - SJG, through its affiliate, South Jersey Resources Group (SJRG) and another counterparty, uses a variety of derivative instruments to limit its exposure to market risk in accordance with strict guidelines (See Note 14).  These contracts, which 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 balance sheets.  The costs or benefits of these short-term contracts are recoverable through SJG’s Basic Gas Supply Service (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 balance sheets.
	SJG 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 balance sheets.  The fair value represents the amount SJG would have to pay the counterparty to terminate these contracts as of those dates.  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 Other Regulatory Assets in the balance sheets.
	Income Taxes - Deferred income taxes are provided for all significant temporary differences between the book and taxable basis of assets and liabilities in accordance with FASB ASC Topic 740 – “Income Taxes” (See Note 6). A valuation allowance is established when it is determined that it is more likely than not that a deferred tax asset will not be realized.
	Cash and Cash Equivalents - For purposes of reporting cash flows, highly liquid investments with original maturities of three months or less are considered cash equivalents.
	NEW ACCOUNTING PRONOUNCEMENTS - Other than as described below, no new accounting pronouncement issued or effective during 2014, 2013 or 2012 had, or is expected to have, a material impact on the financial statements.
	In July 2013, the FASB issued ASU 2013-11, Balance Sheet Presentation of an Unrecognized Income Tax Benefit for a Net Operating Loss or Tax Credit Carryforward. This ASU provides that a liability related to an unrecognized tax benefit should be offset against a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. The new guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this guidance did not have an impact on the Company's financial statement results.
	In May 2014, the 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 services 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. The Company does not expect this standard to have an impact on its financial statements upon adoption.

STOCKBASED_COMPENSATION_PLANS

STOCK-BASED COMPENSATION PLANS	12 Months Ended
	Dec. 31, 2014
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
STOCK-BASED COMPENSATION PLANS	-BASED COMPENSATION PLANS:
	Officers and other key employees of SJG participate in the Stock-Based Compensation Plan (Plan) of SJI. Restricted shares issued under this 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 150% of the original share units granted.
	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.
	Grants containing earnings-based targets are based on SJI's earnings per share (EPS) growth rate relative to a peer group to measure performance. As EPS-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 December 31, 2014, 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		4,001		$	44.38	21.1	%	0.4	%
	Jan. 2013 - EPS		4,001		$	51.18	n/a		n/a
	Jan. 2014 - TSR		5,197		$	42.62	20	%	0.8	%
	Jan. 2014 - EPS		5,197		$	54.44	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, which are reinvested during the three year service period, no reduction to the fair value of the award is required.
	The cost for restricted stock awards was $0.2 million, $0.4 million and $0.4 million in 2014, 2013 and 2012, respectively. Of these costs, approximately one half was capitalized to Utility Plant in each of those years. The cost for 2014 reflects the reversal of approximately $0.2 million of previously recorded costs. This reversal was associated with the January 2012 EPS-based grant for which performance goals were not met.
	As of December 31, 2014, there was $0.5 million of total unrecognized compensation cost related to nonvested share-based compensation awards granted under the restricted stock plans. That cost is expected to be recognized over a weighted average period of 1.7 years.
	The following table summarizes information regarding restricted stock award activity during 2014, excluding accrued dividend equivalents:
		Shares		Weighted
				Average
				Grant Date
				Fair Value
	Nonvested Shares Outstanding, January 1, 2014	15,068		$	50.73
	Granted	10,394		$	48.53
	Vested*	(7,065	)	$	54.08
	Nonvested Shares Outstanding, December 31, 2014	18,397		$	48.2
	* Performance targets during the three-year vesting period were not attained for the January 2012 grant. As a result, no shares will be awarded in 2015.
	Performance targets during the three-year vesting period were not attained for the January 2011 grant that vested at
	December 31, 2013. As a result, no shares were awarded in 2014. During 2013, SJG awarded 12,901 shares that had vested at December 31, 2012, to its officers and other key employees at a market value of $0.6 million. During 2012, SJG awarded 7,098 shares at a market value of $0.4 million. SJG has a policy of making cash payments to SJI to satisfy its obligations under the Plan. Cash payments to SJI during 2014, 2013 and 2012 were approximately $0.4 million, $0.4 million and $0.3 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	12 Months Ended
	Dec. 31, 2014
Public Utilities, General Disclosures [Abstract]
RATES AND REGULATORY ACTIONS	RATES AND REGULATORY ACTIONS:
	Base Rates - SJG is subject to the rules and regulations of the BPU.  In September 2010, the BPU granted SJG a base rate increase of $42.1 million, which was predicated, in part, upon an 8.21% rate of return on rate base that included a 10.3% return on common equity.  The $42.1 million includes $16.6 million of revenue previously recovered through the Conservation Incentive Program (CIP) and $6.8 million of revenues previously recovered through the Capital Investment Recovery Tracker (CIRT), resulting in incremental revenue of $18.7 million.  SJG was permitted to recover regulatory assets contained in its petition and defer certain federally mandated pipeline integrity management program costs for recovery in its next base rate case.  In addition, annual depreciation expense was reduced by $1.2 million as a result of the amortization of excess cost of removal recoveries.  The BPU also authorized a Phase II of the base rate proceeding to review the costs of CIRT projects not rolled into rate base in the September 2010 settlement. A proceeding took place in 2013 to roll into base rates the remaining $22.5 million of CIRT I project costs that were not included in the 2010 rate increase, as well as CIRT II and III investments totaling $95.0 million that were made subsequent to the 2010 base rate case. These costs were rolled into rate base and reflected in base rates effective October 2013.
	In September 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 includes approximately $7.5 million of revenue associated with previously approved Accelerated Infrastructure Replacement Program (AIRP) investments that were rolled into base rates. SJG was also permitted to recover certain regulatory assets and to reduce its composite depreciate rate from 2.4% to 2.1%. These changes became effective on October 1, 2014.
	Rate Mechanisms - SJG's tariff, a schedule detailing the terms, conditions and rate information applicable to its various types of natural gas service, as approved by the BPU, has several primary rate mechanisms as discussed in detail below:
	Basic Gas Supply Service (BGSS) Clause - The BGSS price structure allows SJG to recover all prudently incurred gas costs. BGSS charges to customers can be either monthly or periodic (annual). Monthly BGSS charges are applicable to large use customers and are referred to as monthly because the rate changes on a monthly basis pursuant to a BPU-approved formula based on commodity market prices. Periodic BGSS charges are applicable to lower usage customers, which include all of our residential customers, and are evaluated at least annually by the BPU. However, to some extent, more frequent rate changes to the periodic BGSS are allowed. SJG collects gas costs from customers on a forecasted basis and defers periodic over/under recoveries to the following BGSS year, which runs from October 1 through September 30. If SJG is in a net cumulative undercollected position, gas costs deferrals are reflected on the balance sheet as a regulatory asset. If SJG is in a net cumulative overcollected position, amounts due back to customers are reflected on the balance sheet as a regulatory liability. SJG pays interest on net overcollected BGSS balances at the rate of return on rate base utilized by the BPU to set rates in our last base rate proceeding.
	Regulatory actions regarding the BGSS were as follows:
	•	May 2012 - The BPU issued an Order finalizing the 2011-2012 provisional BGSS rates.
	•	June 2012 - SJG filed its annual BGSS filing with the BPU requesting a $27.0 million, or 8.8%, reduction in gas cost recoveries commencing on October 1, 2012.
	•	September 2012 - The BPU issued an Order approving, on a provisional basis, SJG's request for a $27.0 million, or 8.8%, reduction in gas cost recoveries.
	•	January 2013 - SJG credited the accounts of its periodic BGSS customers with refunds totaling $9.4 million due to gas costs that were lower than projections.
	•	May 2013 - SJG filed its annual BGSS filing with the BPU requesting a $0.6 million reduction in gas cost recoveries.
	•	September 2013 - The BPU issued an Order approving, on a provisional basis, SJG’s request for a $0.6 million reduction in gas cost recoveries.
	•	January 2014 - SJG credited the accounts of its periodic BGSS customer with refunds totaling $11.2 million due to gas costs that were lower than projected.
	•	May 2014 - SJG filed its annual BGSS filing with the BPU requesting a $27.0 million, or a 9.3%, increase in gas cost recoveries.
	•	September 2014 - The BPU issued an Order approving, on a provisional basis, SJG’s request for a $27.0 million increase in gas cost recoveries.
	Conservation Incentive Program (CIP) - The primary purpose of the CIP is to promote conservation efforts, without negatively impacting financial stability, and to base SJG's profit margin on the number of customers rather than the amount of natural gas distributed to customers. In October 2006, the BPU approved the CIP as a three-year pilot program. In January 2010, the BPU approved an extension of this program through September 2013, with an automatic one year extension through September 2014 if a request for an extension was filed by March 2013. A petition was filed in March 2013 to extend the CIP program and in May 2014 the BPU approved the continuation of the CIP. Each CIP year begins October 1 and ends September 30 of the subsequent year. On a monthly basis during the CIP year, SJG records adjustments to earnings based on weather and customer usage factors, as incurred. Subsequent to each year, SJG makes filings with the BPU to review and approve amounts recorded under the CIP. BPU approved cash inflows or outflows generally will not begin until the next CIP year.
	Regulatory actions regarding the CIP were as follows:
	•	May 2012 - The BPU issued an Order finalizing the 2011-2012 provisional CIP rates.
	•	June 2012 - SJG made its annual CIP filing with the BPU requesting recovery of $28.0 million, which includes a $8.4 million non-weather related recovery and a $19.6 million weather related recovery.
	•	September 2012 - The BPU issued an Order approving, on a provisional basis, the 2012-2013 CIP rates filed in June 2012, effective October 1, 2012.
	•	March 2013 - SJG filed a joint petition with another utility requesting modification to, and the continuation of, the CIP program effective October 1, 2013.
	•	May 2013 - SJG made its annual CIP filing with the BPU requesting a reduction in revenue of $17.8 million, which includes a $2.3 million reduction in non-weather related recovery and a $15.5 million reduction in weather related recovery.
	•	September 2013 - The BPU issued an Order approving, on a provisional basis, the 2013-2014 CIP rates filed in May 2013, effective October 1, 2013.
	•	May 2014 - SJG made its annual CIP filing with the BPU requesting a revenue reduction of $21.8 million, which includes a $4.2 million increase in non-weather related revenues and a $26.0 million reduction in weather related revenues.
	•	September 2014 - The BPU issued an Order approving, on a provisional basis, the 2014-2015 CIP rates filed in May 2014, effective October 1 2014.
	Capital Investment Recovery Tracker (CIRT) -  The purpose of the CIRT was to accelerate capital expenditures in an effort to stimulate the economy. The petition requested that we be allowed to earn a return of, and a return on, our investment. In September 2010, the BPU authorized $81.3 million of CIRT-related expenditures to be rolled into rate base and also authorized that the remaining balance of CIRT-related expenditures continue to be recovered. On a monthly basis during the CIRT year, SJG recorded adjustments to earnings based on actual CIRT program expenditures, as incurred.  Annually SJG made filings with the BPU for review and approval of expenditures recorded under the CIRT.
	Regulatory actions regarding the CIRT were as follows:
	•	March 2011 - The BPU approved a CIRT II program allowing SJG to accelerate an additional $60.3 million of capital spending into 2011 and 2012. Under CIRT II, SJG continues to earn a return on investment as the capital is spent, as it did under the original CIRT. The return of investment begins when the investments are rolled into rate base. As such, SJG is permitted to earn a return on CIRT II investments until the roll in is approved and recovery commences.
	•	June 2011 - SJG filed a petition with the BPU requesting the recovery of a portion of CIRT II investments via a roll-in to rate base, and requested to increase the base rates by 0.5%.
	•	October 2011 - SJG filed a petition with the BPU requesting to modify and extend the CIRT II program. The petition requested an additional incremental investment of $40.0 million in 2012 and $50.0 million in 2013.
	•	May 2012 - The BPU approved a modification and extension of the CIRT II program (CIRT III), allowing SJG to accelerate an incremental $35.0 million of capital spending through December 2012.
	•	October 2012 - SJG filed a petition requesting a $13.2 million increase in annual revenues by rolling $110.6 million of CIRT I, II and III investments into base rates.
	•	September 2013 - The BPU approved the base rate roll in of the CIRT I, II and III program investments effective October 2013, resulting in a $15.5 million increase in annual revenue. This approval also concluded Phase II of the 2010 base rate case.
	All CIRT program investments have been rolled into rate base effective October 1, 2013 and the CIRT program is now concluded.
	Accelerated Infrastructure Replacement Program (AIRP) - In July 2012, SJG filed a petition to implement a five-year, $250.0 million Accelerated Infrastructure Replacement Program to replace the annual CIRT programs. In February 2013, the BPU issued an Order approving a $141.2 million program to replace cast iron and unprotected bare steel mains and services over a four-year period, with annual investments of approximately $35.3 million. Pursuant to the Order, AIRP investments are to be reviewed and included in rate base in future base rate proceedings.
	Regulatory actions regarding AIRP were as follows:
	•	September 2014 - The BPU approved SJG’s base rate case, which included a $7.5 million increase in revenues associated with the roll in of $69.9 million of AIRP investments into base rates.
	Storm Hardening and Reliability Program (SHARP) - In September 2013, SJG filed with the BPU an asset hardening program pursuant to which it will invest approximately $280.0 million over seven years to replace low pressure distribution mains and services with high pressure mains and services in coastal areas that are susceptible to flooding during major storm events.
	Regulatory actions regarding SHARP were as follows:
	•	August 2014 - The BPU approved the Storm Hardening and Reliability Program (SHARP), authorizing SJG to invest $103.5 million over three years for system hardening on barrier islands.  SJG will earn on a return on these investments as they are made and will reflect the investments in base rates through annual rate adjustments.
	Energy Efficiency Tracker (EET) - In January 2009, SJG filed a petition with the BPU requesting approval of an Energy Efficiency Program (EEP I) for residential, commercial and industrial customers.  The BPU approved this petition in July 2009. Under this program SJG was permitted to invest $17.0 million over two years in energy efficiency measures to be installed in customer homes and businesses. SJG also recovered incremental operating and maintenance expenses and earn a return of, and return on, program investments.
	Regulatory actions regarding the EET were as follows:
	•	June 2011 - SJG filed our annual 2011-2012 petition requesting approval of a $4.7 million increase in EET recovery. This petition was approved in September 2012, with rates effective October 1, 2012.
	•	October 2011 - SJG filed a petition requesting a modification of the EET with regards to the Combined Heat and Power (CHP) program. The BPU approved this petition in February 2012.
	•	May 2012 - SJG filed a petition requesting the approval of a new Energy Efficiency Program (“EEP II”) and to continue our existing EET to recover all costs associated with the EEP II through a $3.1 million increase in annual revenues. These programs provide customers with increased incentives to reduce their natural gas consumption. In June 2013, the BPU approved the EEP II program in the form of an extension of the existing EEP program, permitting SJG to invest $24.0 million in energy efficiency programs through June 2015. The BPU also approved in June 2013 an extension of the EET with a $2.1 million revenue increase effective July 2013.
	•	June 2012 - SJG filed a petition requesting a continuation of the original Energy Efficiency Program (“EEP I”) to bridge the gap between the expiration of the EEP I program on April 30, 2012, and the implementation of the proposed new EEP II program. This petition was approved by the BPU in August 2012. Also in June 2012, SJG filed its 2012 - 2013 annual EET rate adjustment petition requesting a $5.8 million increase in annual revenues to recover the costs associated with its EEP I program. The BPU approved this petition in September 2014.
	•	May 2013 - SJG filed its annual petition requesting an increase of $2.2 million for current EET programs. The BPU approved this petition in September 2014.
	•	May 2014 - SJG filed its annual EET rate adjustment petition requesting an $1.4 million increase in revenues to recover the costs of, and the allowed return on, prior investments associated with energy efficiency programs. The petition is currently pending.
	•	September 2014 - The BPU approved a revenue increase of $2.2 million associated with the 2012-2013 annual EET rate adjustment filing, with rates effective October 1, 2014.
	•	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.
	Societal Benefits Clause (SBC) - The SBC allows SJG to recover costs related to several BPU-mandated programs. Within the SBC are a Remediation Adjustment Clause (RAC), a New Jersey Clean Energy Program (NJCEP) and a Universal Service Fund (USF) program.
	Regulatory actions regarding the SBC, with the exception of USF which requires separate regulatory filings, were as follows:
	•	July 2011 - SJG made its annual 2011-2012 SBC filing requesting a $31.2 million increase in SBC recoveries. The BPU approved this filing in July 2013.
	•	July 2012 - SJG made its annual 2012-2013 SBC filing requesting an $11.8 million increase in SBC recoveries. The BPU approved this filing in July 2013.
	•	September 2012 - The BPU finalized rates for the 2010-2011 SBC petition effective October 1, 2012.
	•	July 2013 - SJG made its annual 2013-2014 SBC filing requesting a $6.4 million decrease in SBC revenues. The BPU approved this filing in September 2014.
	•	July 2014 - SJG made its annual 2014-2015 SBC filing requesting a $25.7 million decrease in SBC revenues.
	Remediation Adjustment Clause (RAC) - The RAC recovers environmental remediation costs of 12 former gas manufacturing plants (See Note 12). The BPU allows SJG to recover such costs over seven-year amortization periods. The net between the amounts actually spent and amounts recovered from customers is recorded as a regulatory asset, Environmental Remediation Cost Expended - Net. Note that RAC activity affects revenue and cash flows but does not directly affect earnings because of the cost recovery over seven-year amortization periods. As of December 31, 2014 and 2013, we reflected the unamortized remediation costs of $29.5 million and $29.9 million, respectively, on the balance sheet under Regulatory Assets (See Note 4). Since implementing the RAC in 1992, SJG has recovered $106.1 million through rates.
	New Jersey Clean Energy Program (NJCEP) - This mechanism recovers costs associated with SJG's energy efficiency and renewable energy programs. In August 2008, the BPU approved the statewide funding of the NJCEP of $1.2 billion for the years 2009 through 2012. Of this amount, SJG was responsible for expensing approximately $41.5 million over the four-year period. In November 2012, the BPU approved a six-month extension of the program through June 2013. Under this extension, SJG is responsible for $7.5 million of funding. In June 2013, the BPU approved a NJCEP funding level of $345 million through June 2014, of which SJG was responsible for $14.5 million. NJCEP adjustments affect revenue and cash flows but do not directly affect earnings as related costs are deferred and recovered through rates on an on-going basis.
	Universal Service Fund (USF) - The USF is a statewide program through which funds for the USF and Lifeline Credit and Tenants Assistance Programs are collected from customers of all New Jersey electric and gas utilities. USF adjustments affect cash flows but do not directly affect revenue or earnings as related costs are deferred and recovered through rates on an ongoing basis.
	Separate regulatory actions regarding the USF were as follows:
	•	June 2012 - SJG made its annual USF filing, along with the State's other electric and gas utilities, proposing to decrease annual statewide gas revenues by $0.5 million. This proposal was designed to decrease our annual USF revenue by $0.1 million.
	•	September 2012 - The BPU approved the statewide budget of $78.0 million for all of the State's gas utilities. SJG's portion of the total is approximately $8.2 million, which decreased rates effective October 1, 2012, resulting in a $0.1 million decrease to its annual USF recoveries.
	•	June 2013 - SJG made its annual USF filing, along with the State’s other electric and gas utilities, proposing to decrease the statewide gas revenues by $29.4 million. This proposal was designed to decrease SJG's annual USF revenue by $3.7 million.
•	September 2013 - The BPU approved the statewide USF budget of $54.4 million for all the State’s gas utilities.  SJG's portion of the total is approximately $5.8 million, which decreased rates effective October 1, 2013, resulting in a $3.4 million decrease to our USF recoveries.
•	June 2014 - SJG made its annual USF filing, along with the State’s other electric and gas utilities, proposing to increase the statewide gas revenues by $19.9 million. This proposal was designed to increase SJG’s annual USF revenue by $2.6 million.
•	September 2014 - The BPU approved the statewide budget of $71.8 million for all the State’s gas utilities.  SJG's portion of the total is approximately $7.9 million, which increased rates effective October 1, 2014, resulting in a $2.6 million increase to its USF recoveries.
Other Regulatory Matters -
Unbundling - Effective January 10, 2000, the BPU approved full unbundling of SJG's system. This allows all natural gas consumers to select their natural gas commodity supplier. As of December 31, 2014, 38,347 of SJG's customers were purchasing their gas commodity from someone other than us. Customers choosing to purchase natural gas from providers other than the utility are charged for the cost of gas by the marketer. The resulting decrease in SJG's revenues is offset by a corresponding decrease in gas costs. While customer choice can reduce utility revenues, it does not negatively affect SJG's net income or financial condition. The BPU continues to allow for full recovery of prudently incurred natural gas costs through the BGSS. Unbundling did not change the fact that SJG still recover cost of service, including certain deferred costs, through base rates.
Pipeline Integrity Costs - SJG is permitted to defer and recover incremental costs incurred as a result of Pipeline Integrity Management regulations that became effective January 14, 2004, which are aimed at enhancing public safety and reliability. The regulations require that utilities use a comprehensive analysis to assess, evaluate, repair and validate the integrity of certain transmission lines in the event of a leak or failure. As part of our September 2010 base rate increase, SJG was permitted to recover previously deferred pipeline integrity costs incurred through September 2010. As part of SJG's 2014 base rate case, it was permitted to recover previously deferred pipeline integrity costs incurred from October 2010 through June 2014. In addition, SJG is authorized to defer future program costs, including related carrying costs, for recovery in our next base rate proceeding, subject to review by the BPU.  As of December 31, 2014 and 2013, deferred pipeline integrity costs totaled $3.4 million and $2.8 million, respectively, and are included in other regulatory assets (See Note 4).
Superstorm Sandy - In June 2013, SJG filed a petition requesting deferral of $0.7 million of incremental operating and maintenance expenses incurred due to Superstorm Sandy. The BPU approved the recovery of these expenses through base rates in SJG’s 2014 base rate case.
Filings and petitions described above are still pending unless otherwise indicated.

REGULATORY_ASSETS_AND_LIABILIT

REGULATORY ASSETS AND LIABILITIES	12 Months Ended
	Dec. 31, 2014
Regulatory Assets and Liabilities Disclosure [Abstract]
REGULATORY ASSETS AND LIABILITIES	REGULATORY ASSETS AND LIABILITIES:
	The discussion under Note 3, Rates and Regulatory Actions, is integral to the following explanations of specific regulatory assets and liabilities.
	Regulatory Assets at December 31st consisted of the following items (in thousands):
		2014		2013
	Environmental Remediation Costs:
	Expended - Net	$	29,540	$	29,945
	Liability for Future Expenditures	124,308		119,492
	Deferred Asset Retirement Obligation Costs	31,584		31,142
	Deferred Pension and Other Postretirement Benefit Costs	99,040		59,284
	Deferred Gas Costs - Net	32,202		—
	Conservation Incentive Program - Receivable	—		10,526
	Societal Benefit Costs Receivable	385		10,408
	Premium for Early Retirement of Debt	—		955
	Deferred Interest Rate Contracts	7,325		3,735
	Energy Efficiency Tracker	11,247		10,420
	Pipeline Supplier Service Charges	5,441		7,106
	Pipeline Integrity Cost	3,431		2,902
	AFUDC - Equity Related Deferrals	10,781		7,810
	Other Regulatory Assets	1,876		2,356
	Total Regulatory Assets	$	357,160	$	296,081
	Except where noted below, all regulatory assets are or will be recovered through utility rate charges, as detailed in the following discussion. We are currently permitted to recover interest on our Environmental Remediation Costs, Societal Benefit Costs Receivable, Energy Efficiency Tracker and Pipeline Integrity Costs, while the other assets are being recovered without a return on investment.
	Environmental Remediation Costs - We have two regulatory assets associated with environmental costs related to the cleanup of 12 sites where we or our predecessors previously operated gas manufacturing plants. The first asset, Environmental Remediation Cost: Expended - Net, represents what was actually spent to clean up the sites, less recoveries through the RAC and insurance carriers. These costs meet the deferral requirements of GAAP, as the BPU allows us to recover such expenditures through the RAC. The other asset, Environmental Remediation Cost: Liability for Future Expenditures, relates to estimated future expenditures required to complete the remediation of these sites. We recorded this estimated amount as a regulatory asset with the corresponding current and noncurrent liabilities on the balance sheets under the captions Current Liabilities and Regulatory and Other Noncurrent Liabilities. The BPU allows us to recover the deferred costs over seven-year periods after they are spent (See Notes 3 and 12).
	Deferred Asset Retirement Obligation Costs - This regulatory asset  resulted from the recording of asset retirement obligations (ARO) and additional utility plant, primarily related to a legal obligation we have for certain safety requirements upon the retirement of our gas distribution and transmission system. We recover asset retirement costs through rates charged to customers. All related accumulated accretion and depreciation amounts for these ARO represent timing differences in the recognition of retirement costs that we are currently recovering in rates and, as such, we are deferring such differences as regulatory assets.
	Deferred Pension and Other Postretirement Benefit Costs  - The BPU authorized us to recover costs related to postretirement benefits under the accrual method of accounting consistent with  GAAP.  In 2006, our regulatory asset was increased by $37.1 million representing the recognition of the underfunded positions of our pension and other postretirement benefit plans.  Subsequent adjustments to this balance occur annually to reflect changes in the funded positions of these benefit plans caused by changes in actual plan experience as well as assumptions of future experience (See Note 11).
	Deferred Gas Costs - Net - Over/under collections of gas costs are monitored through SJG's BGSS mechanism. Net undercollected gas costs are classified as a regulatory asset and net overcollected gas costs are classified as a regulatory liability (see note 3). Derivative contracts used to hedge natural gas purchases are also included in the BGSS, subject to BPU approval (see note 14). The change from a $19.1 million regulatory liability at December 31, 2013 to a $32.2 million regulatory asset at December 31, 2014 was due to the actual cost of the commodity incurred during 2014 exceeding the gas cost recovered from customers as a result of higher prices.
	Conservation Incentive Program Receivable - The impact of the CIP is recorded as an adjustment to earnings as incurred, while cash recovery under the CIP generally occurs during the subsequent CIP year (see Note 3).
	Societal Benefit Costs Receivable - This regulatory asset primarily represents cumulative costs less recoveries under the USF program (See Note 3).
	Premium for Early Retirement of Debt - At December 31, 2014, this regulatory asset represents unamortized debt issuance costs related to long-term debt refinancings. Unamortized debt issuance costs are being amortized over the term of the new debt issue pursuant to regulatory approval by the BPU.
	Energy Efficiency Tracker - This regulatory asset represents cumulative investments less recoveries under the Energy Efficiency Program (See Note 3).
	Deferred Interest Rate Contracts - These amounts represent the market value of interest rate derivatives as discussed further in Note 13.
	Pipeline Supplier Service Charges - This regulatory asset represents costs necessary to maintain adequate supply and system pressures, which are being recovered on a monthly basis through the BGSS over the term of the underlying supplier contracts (See Note 3).
	Pipeline Integrity Cost - As part of our September 2014 base rate increase, we were permitted to recover previously deferred pipeline integrity costs incurred through September 2014. In addition, we are authorized to defer future program costs, including related carrying costs, for recovery in our next base rate proceeding, subject to review by the BPU (see Note 3).
	AFUDC Equity Related Deferrals - This regulatory asset represents the future revenue to recover the future income taxes related to the deferred tax liability for the equity component of AFUDC. Included in the balance is $3.6 million which is being recovered over a period of three years, as approved by the BPU in SJG’s recent rate case settlement.  The remaining balance is being amortized over the life of the associated utility plant.
	Other Regulatory Assets - Some of the assets included in Other Regulatory Assets are currently being recovered from ratepayers as approved by the BPU. Management believes the remaining deferred costs are probable of recovery from ratepayers through future utility rates.
	Regulatory Liabilities at December 31 consisted of the following items (in thousands):
		2014		2013
	Excess Plant Removal Costs	$	35,940	$	40,029
	Deferred Revenue - Net	—		19,067
	Conservation Incentive Program - Payable	4,700		—
	Other Regulatory Liabilities	1,259		1,853
	Total Regulatory Liabilities	$	41,899	$	60,949
	Excess Plant Removal Costs – Represents amounts accrued in excess of actual utility plant removal costs incurred to date.  As part of our September 2014 base rate increase, we are required to amortize approximately $1.1 million of this balance to depreciation expense each year.
	Deferred Revenues – Net - See previous discussion under "Deferred Gas Costs - Net" above.
	Conservation Incentive Program - Payable - See previous discussion under "Conservation Incentive Program - Receivable" above.
	Other Regulatory Liabilities – All other regulatory liabilities are subject to being returned to ratepayers in future rate proceedings.

RELATED_PARTY_TRANSACTIONS

RELATED PARTY TRANSACTIONS	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
RELATED PARTY TRANSACTIONS	RELATED PARTY TRANSACTIONS:
	We conducted business with our parent, SJI, and several other related parties. A description of each of these affiliates and related transactions is as follows:
	SJI Services, LLC (SJIS) - was a wholly owned subsidiary of SJI, which provided services, such as information technology, human resources, corporate communications, materials purchasing and fleet management to SJI and all of its subsidiaries. SJIS was dissolved effective January 1, 2014. All services previously provided by SJIS are currently being provided by SJI.
	South Jersey Energy Solutions, LLC (SJES) - a wholly owned subsidiary of SJI that serves as a holding company for all of SJI’s nonutility operating businesses:
	•	South Jersey Energy Company (SJE) - a wholly owned subsidiary of SJES and a third party energy marketer that acquires and markets natural gas and electricity to retail end users and provides total energy management services to commercial and industrial customers. We provide SJE with billing services. For SJE’s residential customers, for which we perform billing services, we purchase the related accounts receivable at book value less a factor for potential uncollectible accounts, and assume all risk associated with collection.
	•	South Jersey Resources Group, LLC (SJRG) - a wholly owned subsidiary of SJES and a wholesale gas and risk management business that supplies natural gas storage, commodity and transportation to retail marketers, utility businesses and electricity generators in the mid-Atlantic, Appalachian and southern states. We sell natural gas for resale and capacity release to SJRG and also meet some of our gas purchasing requirements by purchasing natural gas from SJRG. Additionally, SJRG manages our market risk associated with fluctuations in the cost of natural gas by entering into financial derivative contracts on our behalf. The gain or loss associated with these derivative contracts is included in our BGSS and in the SJRG receivable and payable amounts shown below.
	•	Marina Energy LLC (Marina) - a wholly owned subsidiary of SJES and developer, owner and operator of energy related projects. We provide natural gas transportation services to Marina under BPU-approved tariffs.
	•	South Jersey Energy Service Plus, LLC (SJESP) - a wholly owned subsidiary of SJES and an appliance service company. We provide billing services to SJESP.
	Millennium Account Services, LLC (Millennium) - a partnership between SJI and Pepco Holdings, Inc, which reads our utility customers’ meters on a monthly basis for a fee.
	Sales of gas to SJRG and SJE comply with Section 284.02 of the Regulations of the Federal Energy Regulatory Commission (FERC).
	In addition to the above, we provide various administrative and professional services to SJI and each of the affiliates discussed above. Likewise, SJI provides substantial administrative services on our behalf. For certain types of transactions, we served as central processing agents for the related parties discussed above. Amounts due to and due from these related parties for pass-through items are not considered material to the financial statements as a whole.
	A summary of these related party transactions, excluding pass-through items, included in Operating Revenues were as follows (in thousands):
		2014			2013			2012
	Operating Revenues/Affiliates:
	SJRG	$	959		$	1,390		$	884
	Marina	1,083			1,297			841
	Other	—			2			10
	Total Operating Revenues/Affiliates	$	2,042		$	2,689		$	1,735
	Related party transactions, excluding pass-through items, included in Operating Expenses were as follows (in thousands):
		2014			2013			2012
	Costs of Sales/Affiliates
	(Excluding depreciation):
	SJRG	$	15,265		$	14,959		$	9,083
	Derivative (Gains)/Losses (See Note 1):
	SJRG	$	(1,582	)	$	887		$	15,407
	Operations Expense/Affiliates:
	SJI	$	14,110		$	11,990		$	10,870
	SJIS	—			5,531			5,397
	Millennium	2,668			2,686			3,149
	Other	(434		)	(428		)	(500		)
	Total Operations Expense/Affiliates	$	16,344		$	19,779		$	18,916

INCOME_TAXES_AND_CREDITS

INCOME TAXES AND CREDITS	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
INCOME TAXES AND CREDITS	INCOME TAXES AND CREDITS:
	Total income taxes applicable to operations differ from the tax that would have resulted by applying the statutory Federal income tax rate to pre-tax income for the following reasons (in thousands):
		2014			2013			2012
	Tax at Statutory Rate	$	35,482		$	33,974		$	32,183
	Increase (Decrease) Resulting from:
	State Income Taxes	1,935			4,833			5,302
	Amortization of Investment Tax Credits	(211		)	(258		)	(287		)
	ESOP Dividend	(1,109		)	(1,058		)	(1,027		)
	AFUDC	(1,481		)	(916		)	(1,048		)
	Other - Net	279			(1,742		)	(1,412		)
	Net Income Taxes	$	34,895		$	34,833		$	33,711
	The provision for Income Taxes is comprised of the following (in thousands):
		2014			2013			2012
	Current:
	Federal	$	60		$	(53	)	$	(4,635	)
	State	2,642			2,946			(7		)
	Total Current	2,702			2,893			(4,642		)
	Deferred:
	Federal	32,069			27,707			30,477
	State	335			4,491			8,163
	Total Deferred	32,404			32,198			38,640
	Investment Tax Credits	(211		)	(258		)	(287		)
	Net Income Taxes	$	34,895		$	34,833		$	33,711
	Investment Tax Credits are deferred and amortized at the annual rate of 3%, which approximates the life of related assets.
	The net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial reporting and income tax purposes resulted in the following net deferred tax liabilities at December 31 (in thousands):
		2014			2013
	Current:
	Net Operating Loss Carryforward	$	(40,573	)	$	(27,600	)
	Budget Billing - Customer Accounts	1,138			1,152
	Provision for Uncollectibles	(2,676		)	(1,726		)
	Conservation Incentive Program	(2,027		)	4,631
	Section 461 Prepayments	1,026			1,156
	Other	(952		)	(922		)
	Current Deferred Tax Asset - Net	$	(44,064	)	$	(23,309	)
	Noncurrent:
	Book Versus Tax Basis of Property	$	417,178		$	371,684
	Deferred Fuel Costs - Net	22,959			1,330
	Environmental Remediation	13,500			14,392
	Deferred Regulatory Costs	6,333			13,665
	Deferred State Tax	(17,390		)	(15,471		)
	Investment Tax Credit Basis Gross-Up	(77		)	(185		)
	Deferred Pension & Other Post Retirement Benefits	39,891			24,218
	Pension & Other Post Retirement Benefits	(27,782		)	(14,152		)
	Deferred Revenues	(11,452		)	(9,266		)
	Net Operating Loss Carryforward	(12,887		)	(8,764		)
	Other	4,749			3,524
	Noncurrent Deferred Tax Liability – Net	$	435,022		$	380,975
	SJG is included in the consolidated federal income tax return filed by SJI. The actual taxes, including credits, are allocated by SJI to its subsidiaries, generally on a separate return basis except for net operating loss and credit carryforwards. As of December 31, 2014 and December 31, 2013, there were no income taxes due to or from SJI.
	As of December 31, 2014, SJG has total federal net operating loss carryforwards of $152.7 million; $63.0 million will expire in 2031, $4.2 million will expire in 2032 and $85.5 million will expire in 2034 . A valuation allowance is recorded when it is more likely than not that any of our deferred income tax assets will not be realized. We believe that we will generate
	sufficient future taxable income to realize the income tax benefits related to our deferred tax assets.
	A reconciliation of unrecognized tax benefits is as follows (in thousands):
		2014			2013			2012
	Balance at January 1,	$	547		$	503		$	421
	Increase as a result of tax position taken in prior years	5			44			82
	Decrease due to a lapse in the statue of limitations	—			—			—
	Settlements	—			—			—
	Balance at December 31,	$	552		$	547		$	503
	The total unrecognized tax benefits as of December 31, 2014 were $0.6 million, not including $0.7 million of accrued interest and penalties.  The total unrecognized tax benefits as of December 31, 2013 were $0.5 million not including $0.6 million of accrued interest and penalties. The total unrecognized tax benefits as of December 31, 2012 were $0.5 million, not including $0.6 million of accrued interest and penalties. The amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate is not significant.  Our policy is to record interest and penalties related to unrecognized tax benefits as interest expense and other expense respectively. These amounts were not significant in 2014, 2013 or 2012. There have been no material changes to the unrecognized tax benefits during 2014, 2013 or 2012 and we do not anticipate any significant changes in the total unrecognized tax benefits within the next 12 months.
	The unrecognized tax benefits are primarily related to an uncertainty of state income tax issues relating to the Company's nexus in certain states. Federal income tax returns from 2011 forward and state income tax returns from 2012 forward are open and subject to examination.

LONGTERM_DEBT

LONG-TERM DEBT	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
LONG-TERM DEBT	LONG-TERM DEBT:
	A schedule of our long-term debt as of December 31, including current maturities, is as follows (in thousands):
				2014			2013
	Long-Term Debt (A):
	First Mortgage Bonds: (B)
	4.52	%	Series due 2014 (C)	—			11,000
	5.115	%	Series due 2014 (D)	—			10,000
	5.387	%	Series due 2015	10,000			10,000
	5.437	%	Series due 2016	10,000			10,000
	4.6	%	Series due 2016	17,000			17,000
	4.657	%	Series due 2017	15,000			15,000
	7.97	%	Series due 2018	10,000			10,000
	7.125	%	Series due 2018	20,000			20,000
	5.587	%	Series due 2019	10,000			10,000
	3	%	Series due 2024	50,000			50,000
	3.03	%	Series due 2024	35,000			35,000
	3.63	%	Series due 2025	10,000			10,000
	4.84	%	Series due 2026	15,000			15,000
	4.93	%	Series due 2026	45,000			45,000
	4.03	%	Series due 2027	45,000			45,000
	4.01	%	Series due 2030 (E)	50,000			50,000
	4.23	%	Series due 2030 (F)	30,000			—
	3.74	%	Series due 2032	35,000			35,000
	5.55	%	Series due 2033	32,000			32,000
	6.213	%	Series due 2034	10,000			10,000
	5.45	%	Series due 2035	10,000			10,000
	Series A 2006 Tax-Exempt First Mortgage Bonds
	Variable Rate, due 2036 (G)			25,000			25,000
	Variable Rate Bank Term Facility, due 2017 (H)			59,000			—
	Total Long-Term Debt Outstanding			543,000			475,000
	Less Current Maturities (A) (G)			(35,909		)	(21,000		)
	Long-Term Debt			$	507,091		$	454,000
	(A)	Long-term debt maturities and sinking funds requirements for the succeeding five years are as follows (in thousands): 2015, $35,909; 2016, $27,909; 2017, $74,909; 2018, $38,909; 2019, $18,909.
	(B)	Our First Mortgage dated October 1, 1947, as supplemented, securing the First Mortgage Bonds constitutes a direct first mortgage lien on substantially all utility plant.
	(C)	In July 2014, SJG retired $11.0 million aggregate principal amount of 4.52% Medium Term Notes (MTN's) at maturity.
	(D)	In September 2014, SJG retired $10.0 million aggregate principal amount of 5.115% MTN's at maturity.
	(E)	In November 2013, SJG issued $50.0 million aggregate principal amount of 4.01% MTN's due November 2030.
	(F)	In January 2014, SJG issued $30.0 million aggregate principal amount of 4.23% MTN's due January 2030.
	(G)	These variable rate demand bonds bear interest at a floating rate that resets weekly. The interest rate as of December 31, 2014 was 0.08%. Liquidity support on these bonds is provided under a separate letter of credit facility that expires in August, 2015; as such, these bonds have been included in the current portion of long-term debt. These bonds contain no financial covenants.
	(H)	In June 2014, SJG entered into a $200.0 million multiple-draw term facility offered by a syndicate of banks which expires in June 2017. SJG can draw under this facility through June 2016 and this facility bears interest at a floating rate based on LIBOR plus a spread determined by SJG's credit ratings. As of December 31, 2014, SJG had borrowed an aggregate $59.0 million under this facility and the proceeds were used to pay down short-term debt.
	In October 2013, SJG filed a petition with the BPU to issue up to $200.0 million of long term debt securities in various forms including MTN's and unsecured debt, with maturities of more than 12 months, over the next three years. This petition was approved in January 2014. There is no capacity remaining under this petition.

FINANCIAL_INSTRUMENTS

FINANCIAL INSTRUMENTS	12 Months Ended
	Dec. 31, 2014
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 December 31, 2014 and December 31, 2013, the escrowed proceeds, including interest earned, totaled $0.1 million. SJG has a margin account with SJRG in conjunction with SJG's risk management activities as detailed in Note 14. As of December 31, 2014 and December 31, 2013, the balance held with SJRG totaled $0.0 million and $0.5 million, respectively. This account is being closed. During March 2013, SJG established a separate margin account with a counterparty in conjunction with SJG's risk management activities as detailed in Note 14. The funds provided by SJG will increase or decrease as the number and value of outstanding energy-related contracts held with this counterparty changes. As of December 31, 2014 and 2013, the balance held by the counterparty was $7.8 million and $(0.3) million, respectively. The carrying amounts of the Restricted Investments approximate their fair value at December 31, 2014 and December 31, 2013, which would be included in Level 1 of the fair value hierarchy. (See Note 13 - 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 $15.0 million as of both December 31, 2014 and December 31, 2013.  The current portion of these receivables is reflected in Accounts Receivable and the non-current portion is reflected in Long-Term Receivables on the balance sheets.  The carrying amounts noted above are net of unamortized discounts resulting from imputed interest in the amount of $1.3 million as of both December 31, 2014 and December 31, 2013.  The annual amortization to interest is not material to SJG’s financial statements.  The carrying amounts of these receivables approximate their fair value at December 31, 2014 and December 31, 2013, which would be included in Level 2 of the fair value hierarchy. (See Note 13 - 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 that are not carried at fair value, including those financial instruments disclosed in this footnote, approximate their fair values at December 31, 2014 and December 31, 2013, 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 13 - Fair Value of Financial Assets and Financial Liabilities). The estimated fair values of SJG's long-term debt, including current maturities, as of December 31, 2014 and December 31, 2013, were $587.3 million and $486.5 million, respectively.  The carrying amounts of SJG's long-term debt, including current maturities, as of December 31, 2014 and December 31, 2013, were $543.0 million and $475.0 million, respectively.

LINES_OF_CREDIT

LINES OF CREDIT	12 Months Ended
	Dec. 31, 2014
Line of Credit Facility [Abstract]
LINES OF CREDIT	LINES OF CREDIT:
	Credit facilities and available liquidity as of December 31, 2014 were as follows (in thousands):
		Total Facility		Usage		Available Liquidity		Expiration Date
	Commercial Paper Program/ Revolving Credit Facility	$	200,000	$	101,400	$	98,600	May-18
	Uncommitted Bank Lines	10,000		—		10,000		Aug-15
	Total	$	210,000	$	101,400	$	108,600
	The SJG 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 December 31, 2014.
	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, not including letters of credit, during the twelve months ended December 31, 2014 and 2013 were $52.3 million and $91.4 million, respectively.  The maximum amount outstanding under these credit facilities, not including letters of credit, during the twelve months ended December 31, 2014 and 2013 were $105.0 million and $121.9 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 0.45% , 0.37% and 0.48% at December 31, 2014, 2013 and 2012, respectively.

RETAINED_EARNINGS

RETAINED EARNINGS	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
RETAINED EARNINGS	RETAINED EARNINGS:
	Various loan agreements contain potential restrictions regarding the amount of cash dividends or other distributions that we may pay on our common stock. As of December 31, 2014, these loan restrictions did not affect the amount that may be distributed from our retained earnings.
	SJG received $25 million equity infusion from SJI in both 2014 and 2013. No equity infusions were received from SJI in 2012.  Future equity contributions will occur on an as needed basis.

PENSION_AND_OTHER_POSTRETIREME

PENSION AND OTHER POSTRETIREMENT BENEFITS	12 Months Ended
	Dec. 31, 2014
Compensation and Retirement Disclosure [Abstract]
PENSION AND OTHER POSTRETIREMENT BENEFITS	PENSION AND OTHER POSTRETIREMENT BENEFITS:
	We participate in the defined benefit pension plans and other postretirement benefit plans of SJI. The pension plans provide annuity payments to the majority of full-time, regular employees upon retirement. Participation in the SJI qualified defined benefit pension plans was closed to new employees beginning in 2003; however, employees who are not eligible for these pension plans are eligible to receive an enhanced version of SJI’s defined contribution plan. Certain officers of SJG also participate in the non-funded supplemental executive retirement plan (SERP) of SJI, a non-qualified defined benefit pension plan. The other postretirement benefit plans provide health care and life insurance benefits to some retirees.
	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											Other Postretirement Benefits
		2014				2013				2012			2014				2013			2012
	Service Cost	$	3,697			$	4,487			$	3,718		$	585			$	771		$	704
	Interest Cost	8,952				7,886				8,008			2,297				2,221			2,443
	Expected Return on Plan Assets	(10,818		)		(9,435		)		(8,249		)	(2,467		)		(2,158		)	(1,910		)
	Amortization:
	Prior Service Cost (Credits)	177				208				207			133				(195		)	(195		)
	Actuarial Loss	4,864				7,608				6,432			770				1,555			1,534
	Net Periodic Benefit Cost	6,872				10,754				10,116			1,318				2,194			2,576
	Capitalized Benefit Costs	(3,047		)		(5,002		)		(4,684		)	(722		)		(1,172		)	(1,340		)
	Affiliate SERP Allocations	(1,313		)		(1,389		)		(1,107		)	—				—			—
	Total Net Periodic Benefit Expense	$	2,512			$	4,363			$	4,325		$	596			$	1,022		$	1,236
	Capitalized benefit costs reflected in the table above relate to our construction program.
	Companies with publicly traded equity securities that sponsor a postretirement benefit plan are required to fully recognize, as an asset or liability, the overfunded or underfunded status of its benefit plans and recognize changes in the funded status in the year in which the changes occur. Changes in funded status are generally reported in Other Comprehensive Loss; however, since we recover all prudently incurred pension and postretirement benefit costs from our ratepayers, a significant portion of the charges resulting from the recording of additional liabilities under this statement are reported as regulatory assets (See Note 4).
	Details of the activity within the Regulatory Asset and Accumulated Other Comprehensive Loss associated with Pension and Other Postretirement Benefits are as follows (in thousands):
		Regulatory Assets								Accumulated Other Comprehensive Loss (pre-tax)
		Pension Benefits				Other Postretirement Benefits				Pension Benefits			Other Postretirement Benefits
	Balance at January 1, 2013	$	68,713			$	27,184			$	21,908		$	—
	Amounts Arising during the Period:
	Net Actuarial Loss	(20,554		)		(9,171		)		(1,576		)	—
	Amounts Amortized to Net Periodic Costs:
	Net Actuarial Loss	(5,319		)		(1,555		)		(2,289		)	—
	Prior Service (Cost) Credit	(208		)		194				—			—
	Balance at December 31, 2013	42,632				16,652				18,043			—
	Amounts Arising during the Period:
	Net Actuarial Loss	31,075				7,826				7,102			—
	Prior Service Cost (Credit)	486				4,146				—
	Amounts Amortized to Net Periodic Costs:
	Net Actuarial Loss	(2,841		)		(628		)		(1,975		)	—
	Prior Service (Cost) Credit	(175		)		(133		)		—			—
	Balance at December 31, 2014	$	71,177			$	27,863			$	23,170		$	—
	The estimated costs that will be amortized from Regulatory Assets into net periodic benefit costs in 2014 are as follows (in thousands):
		Pension Benefits				Other Postretirement Benefits
	Prior Service Costs	$	199			$	499
	Net Actuarial Loss	$	5,922			$	1,235
	The estimated costs that will be amortized from Accumulated Other Comprehensive Loss into net periodic benefit costs in 2015 are as follows (in thousands):
		Pension Benefits				Other Postretirement Benefits
	Net Actuarial Loss	$	2,750			$	—
	A reconciliation of the plans’ benefit obligations, fair value of plan assets, funded status and amounts recognized in our balance sheets follows (in thousands):
										Other
		Pension Benefits								Postretirement Benefits
		2014				2013				2014			2013
	Change in Benefit Obligations:
	Benefit Obligation at Beginning of Year	$	180,668			$	186,899			$	50,915		$	55,615
	Service Cost	3,697				4,487				585			771
	Interest Cost	8,952				7,886				2,297			2,221
	Actuarial (Gain) Loss	35,634				(11,514		)		6,008			(4,552		)
	Retiree Contributions	—				—				452			335
	Plan Amendments	534				—				4,146			—
	Benefits Paid	(7,880		)		(7,090		)		(3,733		)	(3,475		)
	Benefit Obligation at End of Year	$	221,605			$	180,668			$	60,670		$	50,915
	Change in Plan Assets:
	Fair Value of Plan Assets at Beginning of Year	$	142,674			$	119,391			$	39,471		$	32,694
	Actual Return on Plan Assets	8,275				20,049				507			5,101
	Employer Contributions	1,499				10,324				4,254			4,816
	Retiree Contributions	—				—				452			335
	Benefits Paid	(7,880		)		(7,090		)		(3,733		)	(3,475		)
	Fair Value of Plan Assets at End of Year	$	144,568			$	142,674			$	40,951		$	39,471
	Funded Status at End of Year:
	Accrued  Net Benefit Cost at End of Year	$	(77,037	)		$	(37,994	)		$	(19,719	)	$	(11,444	)
	Amounts Recognized in the Statement of Financial Position Consist of:
Current Liabilities	$	(1,515	)		$	(1,241	)		$	—		$	—
Noncurrent Liabilities	(75,522		)		(36,753		)		(19,719		)	(11,444		)
Net Amount Recognized at End of Year	$	(77,037	)		$	(37,994	)		$	(19,719	)	$	(11,444	)
Amounts Recognized in Regulatory Assets Consist of:
Prior Service Costs	$	944			$	634			$	4,965		$	952
Net Actuarial Loss	70,233				41,998				22,898			15,700
Net Amount Recognized at End of Year	$	71,177			$	42,632			$	27,863		$	16,652
Amounts Recognized in Accumulated Other Comprehensive Loss Consist of:
Net Actuarial Loss	$	23,170			$	18,043			$	—		$	—
The projected benefit obligation (PBO) and accumulated benefit obligation (ABO) of our qualified employee pension plans were $176.3 million and $161.3 million, respectively, as of December 31, 2014; and $143.5 million and $131.4 million, respectively, as of December 31, 2013. The ABO of these plans exceeded the value of the plan assets as of December 31, 2014. The value of these assets were $144.6 million and $142.7 million as of December 31, 2014 and 2013, respectively, and can be seen in the tables above. The PBO and ABO for our non-funded SERP were $45.3 million and $44.0 million, respectively, as of December 31, 2014; and $37.2 million and $36.2 million, respectively, as of December 31, 2013. The SERP obligation is reflected in the tables above and has no assets.
The weighted-average assumptions used to determine benefit obligations at December 31 were:
	Pension Benefits						Other Postretirement Benefits
	2014			2013			2014			2013
Discount Rate	4.25	%		5.09	%		4.2	%		4.91	%
Rate of Compensation Increase	3.5	%		3.5	%		3.5	%		3.5	%
The weighted-average assumptions used to determine net periodic benefit cost for years ended December 31 were:
	Pension Benefits									Other Postretirement Benefits
	2014			2013			2012			2014		2013			2012
Discount Rate	5.09	%		4.26	%		5.03	%		4.91	%	4.14	%		4.92	%
Expected Long-Term Return on Plan Assets	7.75	%		7.5	%		7.5	%		6.25	%	6.6	%		6.6	%
Rate of Compensation Increase	3.5	%		3.25	%		3.25	%		3.5	%	3.25	%		3.25	%
Obligations as of December 31, 2013, disclosed herein reflect the use of the RP 2000 mortality tables.  In 2014, the Society of Actuaries released new mortality tables (RP-2014 base table with MP-2014 generational projection scale), which indicate that the average life expectancy of both our active and retired plan participants has increased. Obligations as of December 31, 2014, disclosed herein reflect the use of the new tables. While the adoption of the new tables increase liabilities significantly as of December 31, 2014, no impact on expense will occur until 2015.
The discount rates used to determine the benefit obligations at December 31, 2014 and 2013, which are used to determine the net periodic benefit cost for the subsequent year, were based on a portfolio model of high-quality investments with maturities that match the expected benefit payments under our pension and other postretirement benefit plans.
The expected long-term return on plan assets (“return”) has been determined by applying long-term capital market projections provided by our pension plan Trustee to the asset allocation guidelines, as defined in the Company’s investment policy, to arrive at a weighted average return.  For certain other equity securities held by an investment manager outside of the control of the Trustee, the return has been determined based on historic performance in combination with long-term expectations.  The return for the other postretirement benefits plan is determined in the same manner as discussed above; however, the expected return is reduced based on the taxable nature of the underlying trusts.
The assumed health care cost trend rates at December 31 were:
	2014			2013
Medical Care and Drug Cost Trend Rate Assumed for Next Year	7	%		7	%
Dental Care Cost Trend Rate Assumed for Next Year	4.75	%		4.75	%
Rate to which Cost Trend Rates are Assumed to Decline (the Ultimate Trend Rate)	4.75	%		4.75	%
Year that the Rate Reaches the Ultimate Trend Rate	2023			2023
Assumed health care cost trend rates have a significant effect on the amounts reported for our postretirement health care plans. A one-percentage-point change in assumed health care cost trend rates would have the following effects (in thousands):
	1-Percentage-				1-Percentage-
	Point Increase				Point Decrease
Effect on the Total of Service and Interest Cost	$	112			$	(94	)
Effect on Postretirement Benefit Obligation	$	3,806			$	(3,065	)
PLAN ASSETS — The Company’s overall investment strategy for pension plan assets is to achieve a diversification by asset class, style of manager, and sector and industry limits to achieve investment results that match the actuarially assumed rate of return, while preserving the inflation adjusted value of the plans.  The Company has implemented this diversification strategy primarily with commingled common/collective trust funds.  The target allocations for pension plan assets are 28-48 percent U.S. equity securities, 13-25 percent international equity securities, 32-42 percent fixed income investments, and 2-14 percent to all other types of investments.  Equity securities include investments in commingled common/collective trust funds as well as large-cap, mid-cap and small-cap companies.  Fixed income securities include commingled common/collective trust funds, group annuity contracts for pension payments, and hedge funds.  Other types of investments include investments in private equity funds and real estate funds that follow several different strategies.
The strategy recognizes that risk and volatility are present to some degree with all types of investments.  We seek to avoid high levels of risk at the total fund level through diversification by asset class, style of manager, and sector and industry limits.  Specifically prohibited investments include, but are not limited to, venture capital, margin trading, commodities and securities of companies with less than $250.0 million capitalization (except in the small-cap portion of the fund where capitalization levels as low as $50.0 million are permissible).  These restrictions are only applicable to individual investment managers with separately managed portfolios and do not apply to mutual funds or commingled trusts.
SJG evaluated its pension and other postretirement benefit plans’ asset portfolios for the existence of significant concentrations of credit risk as of December 31, 2014.   Types of concentrations that were evaluated include, but are not limited to, investment concentrations in a single entity, type of industry, foreign country, and individual fund.  As of December 31, 2014, there were no significant concentrations (defined as greater than 10 percent of plan assets) of risk in SJG’s pension and other postretirement benefit plan assets.
GAAP establishes a hierarchy that prioritizes fair value measurements based on the types of inputs used for the various valuation techniques.  This hierarchy groups assets into three (3) distinct levels as fully described in Note 13, that will serve as the basis for presentation throughout the remainder of this Note.
The fair values of SJG’s pension plan assets at December 31, 2014 and 2013 by asset category are as follows (in thousands):
Asset Category	Total				Level 1				Level 2			Level 3
As of December 31, 2014:
Cash / Cash Equivalents:
Common/Collective Trust Funds (a)	$	554			$	—			$	554		$	—
STIF-Type Instrument (b)	1,003				—				1,003			—
Equity securities:
Common/Collective Trust Funds – U.S. (a)	41,000				—				41,000			—
Common/Collective Trust Funds – International (a)	24,796				—				24,796			—
U.S. Large-Cap (c)	10,380				10,380				—			—
U.S. Mid-Cap (c)	4,122				4,122				—			—
U.S. Small-Cap (c)	186				186				—
International (c)	2,698				2,698				—			—
Fixed Income:
Common/Collective Trust Funds (a)	38,740				—				38,740			—
Guaranteed Insurance Contract (d)	8,738				—				—			8,738
Hedge Funds (e)	3,469				—				—			3,469
Other types of investments:
Private Equity Fund (f)	2,895				—				—			2,895
Common/Collective Trust Fund – Real Estate (g)	5,987				—				—			5,987
Total	$	144,568			$	17,386			$	106,093		$	21,089
Asset Category	Total				Level 1				Level 2			Level 3
As of December 31, 2013:
Cash / Cash Equivalents:
Common/Collective Trust Funds (a)	$	334			$	—			$	334		$	—
STIF-Type Instrument (b)	943				—				943			—
Equity securities:
Common/Collective Trust Funds – U.S. (a)	41,527				—				41,527			—
Common/Collective Trust Funds – International (a)	27,312				—				27,312			—
U.S. Large-Cap (c)	9,342				9,342				—			—
U.S. Mid-Cap (c)	3,313				3,313				—			—
International (c)	2,935				2,935				—			—
Fixed Income:
Common/Collective Trust Funds (a)	36,728				—				36,728			—
Guaranteed Insurance Contract (d)	9,071				—				—			9,071
Hedge Funds (e)	3,328				—				—			3,328
Other types of investments:												—
Private Equity Fund (f)	2,440				—				—			2,440
Common/Collective Trust Fund – Real Estate (g)	5,401				—				—			5,401
Total	$	142,674			$	15,590			$	106,844		$	20,240
(a)	This category represents common/collective trust fund investments through a commingled employee benefit trust (excluding real estate).  These commingled funds are not traded publicly; however, the majority of the underlying assets held in these funds are stocks and bonds that are traded on active markets and prices for these assets are readily observable.  Also included in these funds are interest rate swaps, asset backed securities, mortgage backed securities and other investments with observable market values. Holdings in these commingled funds are classified as Level 2 investments.
(b)	This category represents short-term investment funds held for the purpose of funding disbursement payment arrangements.  Underlying assets are valued based on quoted prices in active markets, or where quoted prices are not available, based on models using observable market information.  Since not all values can be obtained from quoted prices in active markets, these funds are classified as Level 2 investments.
(c)	This category of equity investments represents a managed portfolio of common stock investments in five sectors: telecommunications, electric utilities, gas utilities, water and energy.  These common stocks are actively traded on exchanges and price quotes for these shares are readily available.  These common stocks are classified as Level 1 investments.
(d)	This category represents SJI’s Group Annuity contracts with a nationally recognized life insurance company.  The contracts are the assets of the plan, while the underlying assets of the contracts are owned by the contract holder.  Valuation is based on a formula and calculation specified within the contract.  Since the valuation is based on the reporting entity’s own assumptions, these contracts are classified as Level 3 investments.
(e)	This category represents a collection of underlying funds which are all domiciled outside of the United States. All of the underlying fund managers are based in the U.S.; however, they do not necessarily trade only in the U.S. markets. The fair value of these funds is determined by the underlying fund's general partner or manager. These funds are classified as Level 3 investments.
(f)	This category represents a limited partnership which includes several investments in U.S. leveraged buyout, venture capital, and special situation funds.  Fund valuations are reported on a 90 day lag and, therefore, the value reported herein represents the market value as of September 30, 2014 and 2013, respectively.  The fund’s investments are stated at fair value, which is generally based on the valuations provided by the general partners or managers of such investments.  Fund investments are illiquid and resale is restricted.  These funds are classified as Level 3 investments.
(g)	This category represents real estate common/collective trust fund investments through a commingled employee benefit trust. These commingled funds are part of a direct investment in a pool of real estate properties. These funds are valued by investment managers on a periodic basis using pricing models that use independent appraisals from sources with professional qualifications. Since these valuation inputs are not highly observable, the real estate funds are classified as Level 2 investments.
Fair Value Measurement Using Significant
Unobservable Inputs (Level 3)
(In thousands)
	Guaranteed				Hedge				Private			Real				Total
	Insurance				Funds				Equity			Estate
	Contract								Funds
Balance at January 1, 2013	$	9,898			$	—			$	2,557		$	4,778			$	17,233
Actual return on plan assets:
Relating to assets still held at the reporting date	(68		)		124				80			623				759
Relating to assets sold during the period	14				—				345			—				359
Purchases, Sales and Settlements	(773		)		3,204				(542		)	—				1,889
Balance at December 31, 2013	$	9,071			$	3,328			$	2,440		$	5,401			$	20,240
Actual return on plan assets:
Relating to assets still held at the reporting date	396				141				(20		)	586				1,103
Relating to assets sold during the period	10				—				260			—				270
Purchases, Sales and Settlements	(739		)		—				215			—				(524		)
Balance at December 31, 2014	$	8,738			$	3,469			$	2,895		$	5,987			$	21,089
As with the pension plan assets, the Company’s overall investment strategy for post-retirement benefit plan assets is to achieve a diversification by asset class, style of manager, and sector and industry limits to achieve investment results that match the actuarially assumed rate of return, while preserving the inflation adjusted value of the plans.  The Company has implemented this diversification strategy with a mix of common/collective trust funds, mutual funds and Company-owned life insurance policies.  The target allocations for post-retirement benefit plan assets are 33-43 percent U.S. equity securities, 20-30 percent international equity securities, and 32-42 percent fixed income investments.  Equity securities include investments in large-cap, mid-cap and small-cap companies within mutual funds or common/collective trust funds.  Fixed income securities within the common/collective trust fund include primarily investment grade, U.S. Government and mortgage-backed financial instruments. The insurance policies are backed by a series of commingled trust investments held by the insurance carrier.
The fair values of SJG’s other postretirement benefit plan assets at December 31, 2014 and 2013 by asset category are as follows (in thousands):
Asset Category	Total				Level 1				Level 2			Level 3
As of December 31, 2014:
Cash	$	142			$	142			$	—		$	—
Equity Securities:
Common/Collective Trust Funds - U.S. (a)	10,006				—				10,006			$	—
Common/Collective Trust Funds - International (a)	7,030				—				7,030			—
Mutual Fund - U.S. (b)	4,447				4,447				—			—
Mutual Funds - International (b)	1,671				1,671				—			—
Fixed Income:
Common/Collective Trust Funds - Bonds (a)	11,059				—				11,059			—
Mutual Funds - Bonds (b)	2,624				2,624				—			—
Other Types of Investments:
Mutual Funds - REITS (b)	286				286				—			—
Company Owned Life Insurance (c)	3,686				—				3,686			—
Total	$	40,951			$	9,170			$	31,781		$	—
Asset Category	Total				Level 1				Level 2			Level 3
As of December 31, 2013:
Equity Securities:
Common/Collective Trust Funds - U.S. (a)	$	12,412			$	—			$	12,412		$	—
Common/Collective Trust Funds - International (a)	10,031				—				10,031			—
Mutual Fund - U.S. (b)	2,814				2,814				—			—
Fixed Income:
Common/Collective Trust Funds - Bonds (a)	14,214				—				14,214			—
Total	$	39,471			$	2,814			$	36,657		$	—
(a)	This category represents common/collective trust fund investments through a commingled employee benefit trust (excluding real estate).  These commingled funds are not traded publicly; however, the majority of the underlying assets held in these funds are stocks and bonds that are traded on active markets and prices for these assets are readily observable.  Also included in these funds are interest rate swaps, asset backed securities, mortgage backed securities and other investments with observable market values. Holdings in these commingled funds are classified as Level 2 investments.
(b)	This category represents mutual fund investments. The mutual funds are actively traded on exchanges and price quotes for the shares are readily available. These mutual funds are classified as Level 1 investments.
(c)	This category represents Company-owned life insurance policies with a nationally known life insurance company. The value of these policies is backed by a series of common/collective trust funds held by the insurance carrier similar to category (a) above. Holdings in these insurance policies are classified as Level 2 investments.
Future Benefit Payments - The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid during the following years (in thousands):
	Pension Benefits				Other
					Postretirement Benefits
2015	$	8,444			$	3,999
2016	$	8,886			$	4,199
2017	$	9,143			$	4,222
2018	$	10,263			$	4,285
2019	$	11,174			$	4,389
2020 - 2024	$	65,205			$	23,421
Contributions - No pension plan contributions were made to our qualified employee pension plans during the year ended December 31, 2014 . SJG contributed$9.1 million to our qualified employee pension plans during the year ended December 31, 2013. In January 2015, SJG made a pension plan contribution of $12.0 million.  Payments related to the unfunded SERP plan are expected to approximate $1.5 million in 2015 and have been consistent over the past few years. We also have a regulatory obligation to contribute approximately $3.6 million annually to our other postretirement benefit plans’ trusts, less costs incurred directly by us.
Defined Contribution Plan - We also offer an Employees’ Retirement Savings Plan (Savings Plan) to eligible employees. For employees eligible for participation in SJI's defined benefit pension plans, SJG matches 50% of participants’ contributions up to 6% of base compensation. For employees who are not eligible for participation in SJI’s defined benefit plans, we match 50% of participants’ contributions up to 8% of base compensation. Employees not eligible for the pension plans also receive a year-end contribution of $1,500 if 10 or fewer years of service, or $2,000 if more than 10 years of service. The amount expensed and contributed for the matching provision of the Savings Plan approximated $1.2 million, $1.0 million and $0.9 million for the years ended December 31, 2014, 2013 and 2012, respectively.

COMMITMENTS_AND_CONTINGENCIES

COMMITMENTS AND CONTINGENCIES	12 Months Ended
	Dec. 31, 2014
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 the 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.
	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 $0.5 million related to all claims in the aggregate, as of both December 31, 2014 and December 31, 2013. 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 59% of our workforce at December 31, 2014. The Company has collective bargaining agreements with two unions who represent these employees: the International Brotherhood of Electrical Workers (IBEW) that operates under a collective bargaining agreement that runs through February 28, 2017. The remaining unionized employees are represented by the International Association of Machinists and Aerospace Workers (IAM). Employees represented by the IAM operate under a collective bargaining agreement that runs through August 2017.
	Environmental Remediation Costs - We incurred and recorded costs for environmental cleanup of 12 sites where we or our predecessors operated gas manufacturing plants. We stopped manufacturing gas in the 1950s.
	We successfully entered into settlements with all of our historic comprehensive general liability carriers regarding the environmental remediation expenditures at our sites. Also, we had purchased a Cleanup Cost Cap Insurance Policy limiting the amount of remediation expenditures that we were required to make at 11 of our sites. This policy provided coverage up to $50.0 million, which was exhausted in 2012.
	Since the early 1980s, we accrued environmental remediation costs of $343.9 million, of which $219.6 million has been spent as of December 31, 2014. The following table details the amounts accrued and expended for environmental remediation at December 31 (in thousands):
		2014			2013
	Beginning of Year	$	119,492		$	107,410
	Accruals	16,453			22,264
	Expenditures	(11,637		)	(10,182		)
	End of Year	$	124,308		$	119,492
	The balances are segregated between current and noncurrent on the balance sheets under the captions Current Liabilities and Regulatory and Other Noncurrent Liabilities.
	Management estimates that undiscounted future costs to clean up our sites will range from $124.3 million to $223.3 million. We recorded the lower end of this range, $124.3 million, as a liability because a single reliable estimation point is not feasible due to the amount of uncertainty involved in the nature of projected remediation efforts and the long period over which remediation efforts will continue. Six of our sites comprise the majority of these estimates, the sum of the six sites range from a low of $110.2 million to a high of $198.4 million. Recorded amounts include estimated costs based on projected investigation and remediation work plans using existing technologies. Actual costs could differ from the estimates due to the long-term nature of the projects, changing technology, government regulations and site-specific requirements. Significant risks surrounding these estimates include unforeseen market price increases for remedial services, property owner acceptance of remedy selection, regulatory approval of selected remedy and remedial investigative findings.
	The remediation efforts at our six most significant sites include the following:
	Site 1 - Several interim remedial actions have been completed at the site. Steps remaining to remediate the balance of the site include selection of the remedial action, confirmation of regulatory compliance of the selected remedy, implementation of the approved remedy and issuance of a Response Action Outcome.
	Site 2 - Remediation of the site is underway in accordance with the approved Remedial Action Work plan. Steps remaining to remediate the site include continued excavation of impacted soil and post remediation groundwater monitoring and issuance of a Response Action Outcome.
	Site 3 - Various remedial investigation activities have been completed at this site and a final site remedy has been proposed to the regulatory authority. Steps remaining to remediate the site include installation of a sub-surface containment unit, operation of a product recovery system, post remediation groundwater monitoring, and issuance of a Response Action Outcome.
	Site 4 - Remedial investigation activities are ongoing at this site including pilot studies of potential remedial alternatives and continued soil and groundwater investigation.  Steps remaining to remediate the site include in-situ remediation of impacted soil, post remediation groundwater monitoring, and issuance of a Response Action Outcome.
	Sites 5 and 6 - Remedial investigation activities are ongoing at these sites.  Steps remaining to remediate the sites include selection of the remedial action, approval of the selected remedy, implementation of the remedy, and issuance of a Response Action Outcome.

FAIR_VALUE_OF_FINANCIAL_ASSETS

FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES	12 Months Ended
	Dec. 31, 2014
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 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	$	—
	As of December 31, 2013
		Total		Level 1		Level 2		Level 3
	Assets
	Available-for-Sale Securities (A)	$	8,696	$	8,696	$	—	$	—
	Derivatives – Energy Related Assets (B)	1,500		1,409		91		—
		$	10,196	$	10,105	$	91	$	—
	Liabilities
	Derivatives – Energy Related Liabilities (B)	$	759	$	155	$	604	$	—
	Derivatives – Other (C)	3,735		—		3,735		—
		$	4,494	$	155	$	4,339	$	—
	(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	12 Months Ended
	Dec. 31, 2014
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 December 31, 2014, SJG had outstanding NYMEX contracts intended to limit the exposure to market risk on 8.9 MMdts of expected future purchases of natural gas and 0.6 MMdts of expected future sales of natural gas. In addition to these derivative contracts, SJG had basis related purchase and sales contracts totaling 3.7 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 balance sheets. The costs or benefits of these short-term contracts are recoverable through SJG’s Basic Gas Supply Service (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 balance sheets. As of December 31, 2014 and December 31, 2013, SJG had $5.6 million of unrealized losses and $0.7 million of unrealized gains, respectively, included in its BGSS related to open financial contracts.
	The Company has also entered into interest rate derivatives to manage 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 balance sheets. The fair value represents the amount SJG would have to pay the counterparty to terminate these contracts as of those dates. 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 balance sheets.
	We previously used derivative transactions known as “Treasury Locks” to mitigate 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 both December 31, 2014 and December 31, 2013, the unamortized balance was approximately $1.0 million.
	As of December 31, 2014, SJG’s active interest rate swaps were as follows:
	Notional Amount				Fixed Interest Rate			Start Date	Maturity		Type of Debt		Obligor
	$	12,500,000			3.43	%		12/1/06	2/1/36		Tax-exempt		SJG
	$	12,500,000			3.43	%		12/1/06	2/1/36		Tax-exempt		SJG
	The fair values of all derivative instruments, as reflected in the balance sheets as of December 31, 2014 and December 31, 2013, are as follows (in thousands):
	Derivatives not designated as hedging instruments under GAAP		2014							2013
			Assets				Liabilities			Assets				Liabilities
	Energy related commodity contracts:
	Derivatives – Energy Related – Current		$	2,051			$	6,305		$	1,222			$	711
	Derivatives – Energy Related – Non-Current		—				1,298			278				48
	Interest rate contracts:
	Derivatives – Other		—				7,325			—				3,735
	Total derivatives not designated as hedging instruments under GAAP		$	2,051			$	14,928		$	1,500			$	4,494
	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 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		)
	As of December 31, 2013
	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		$	1,500			$	—		$	1,500			$	(155	)	(A)	$	(498	)	$	847
	Derivatives - Energy Related Liabilities		(759		)		—			(759		)		155			(B)	—			(604		)
	Derivatives - Other		(3,735		)		—			(3,735		)		—				—			(3,735		)
	(A) The balances at December 31, 2014 and December 31, 2013 were related to derivative liabilities which can be net settled against derivative assets.
	(B) The balances at December 31, 2014 and December 31, 2013 were related to derivative assets which can be net settled against derivative liabilities.
	The effect of derivative instruments on the statements of income for 2014 , 2013 and 2012 are as follows (in thousands):
		Year ended December 31,
	Derivatives in Cash Flow Hedging Relationships	2014				2013			2012
	Interest Rate Contracts:
	Losses reclassified from accumulated OCI into income (a)	$	(46	)		$	(46	)	$	(46	)
	(a) Included in Interest Charges
	Net realized gains (losses) associated with SJG’s energy-related financial commodity contracts of $1.7 million, $(0.4) million and $(15.4) million for 2014, 2013 and 2012, 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 and there is no impact on earnings.

ACCUMULATED_OTHER_COMPREHENSIV

ACCUMULATED OTHER COMPREHENSIVE LOSS (AOCL)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
ACCUMULATED OTHER COMPREHENSIVE LOSS (AOCL)	ACCUMULATED OTHER COMPREHENSIVE LOSS (AOCL):
	The following tables summarizes the changes in accumulated other comprehensive loss (AOCL) for the years ended December 31, 2014 and 2013, respectively (in thousands):
		Postretirement Liability Adjustment				Unrealized Gain (Loss) on Derivatives-Other				Unrealized Gain (Loss) on Available-for-Sale Securities			Total
	Balance at January 1, 2014 (a)	(10,672		)		(594		)		$	397		$	(10,869	)
	Other comprehensive income before reclassifications	(4,345		)		—				76			(4,269		)
	Amounts reclassified from AOCL (b)	1,180				27				(548		)	659
	Net current period other comprehensive income	(3,165		)		27				(472		)	(3,610		)
	Balance at December 31, 2014 (a)	$	(13,837	)		$	(567	)		$	(75	)	$	(14,479	)
		Postretirement Liability Adjustment				Unrealized Gain (Loss) on Derivatives-Other				Unrealized Gain (Loss) on Available-for-Sale Securities			Total
	Balance at January 1, 2013 (a)	$	(12,958	)		$	(621	)		$	294		$	(13,285	)
	Other comprehensive income before reclassifications	932				—				592			1,524
	Amounts reclassified from AOCL (b)	1,354				27				(489		)	892
	Net current period other comprehensive income	2,286				27				103			2,416
	Balance at December 31, 2013 (a)	$	(10,672	)		$	(594	)		$	397		$	(10,869	)
	(a) Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.
	(b) See table below.
	The reclassifications out of AOCL for the years ended December 31, 2014 and 2013 is as follows (in thousands):
	Components of AOCL	Amounts Reclassified from AOCL							Affected Line Item in the Statements of Income
		For the Year Ended December 31, 2014			For the Year Ended December 31, 2013
	Unrealized Loss on Derivatives-Other - Interest Rate Contracts designated as cash flow hedges	$	46		$	46			Interest Charges
	Unrealized Gain on Available-for-Sale Securities	(918		)	(828		)		Other Income & Expense
	Actuarial Loss on Postretirement Benefits	1,975			2,289				Operating Expenses: Operations
		1,103			1,507				Loss (Income) Before Income Taxes
	Income Taxes (a)	444			615				Income Taxes (a)
	Losses (Gains) from reclassifications for the period net of tax	$	659		$	892
	(a) Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.

QUARTERLY_RESULTS_OF_OPERATION

QUARTERLY RESULTS OF OPERATIONS - UNAUDITED	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
QUARTERLY RESULTS OF OPERATIONS - UNAUDITED	QUARTERLY RESULTS OF OPERATIONS - UNAUDITED:
	The summarized quarterly results of our operations are as follows (in thousands):
		2014 Quarter Ended								2013 Quarter Ended
		31-Mar		30-Jun		Sept. 30		Dec. 31		31-Mar		30-Jun		Sept. 30		Dec. 31
	Operating Revenues	$	210,545	$	69,159	$	60,952	$	161,219	$	174,098	$	66,536	$	59,674	$	146,172
	Expenses:
	Cost of Sales (excluding depreciation)	103,293		24,879		23,400		79,644		77,602		26,108		24,717		71,654
	Operations and Maintenance
	Including Fixed Charges	46,969		38,737		37,432		47,943		38,659		33,871		33,249		39,486
	Income Taxes	22,527		2,379		534		9,455		20,771		2,269		471		11,322
	Energy and Other Taxes	1,185		830		798		947		3,003		1,277		1,052		2,530
	Total Expenses	173,974		66,825		62,164		137,989		140,035		63,525		59,489		124,992
	Other Income and Expense	1,086		1,477		2,186		811		1,450		810		764		773
	Net Income	$	37,657	$	3,811	$	974	$	24,041	$	35,513	$	3,821	$	949	$	21,953
	NOTE: Because of the seasonal nature of our business, statements for the three-month periods are not indicative of the results for a full year.

SCHEDULE_II_VALUATION_AND_QUAL

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS	12 Months Ended
	Dec. 31, 2014
Valuation and Qualifying Accounts [Abstract]
SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS	SOUTH JERSEY GAS COMPANY
	SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS
	(In Thousands)
	Col. A	Col. B		Col. C					Col. D		Col. E
				Additions
	Classification	Balance at Beginning of Period		Charged to Costs and		Charged to Other Accounts -			Deductions -		Balance at End
				Expenses		Describe (a)			Describe (b)		of Period
	Provision for Uncollectible
	Accounts for the Year Ended
	31-Dec-14	$	4,553	$	9,417	$	(102	)	$	7,267	$	6,601
	Provision for Uncollectible
	Accounts for the Year Ended
	31-Dec-13	$	3,985	$	4,232	$	(41	)	$	3,623	$	4,553
	Provision for Uncollectible
	Accounts for the Year Ended
	31-Dec-12	$	3,060	$	4,775	$	110		$	3,960	$	3,985
	(a) Recoveries of accounts previously written off and minor adjustments.
	(b) Uncollectible accounts written off.

SUMMARY_OF_SIGNIFICANT_ACCOUNT1

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
The Entity	The Entity - South Jersey Industries, Inc. (SJI) owns all of the outstanding common stock of South Jersey Gas Company (SJG). In our opinion, the 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.
	Certain reclassifications have been made to the prior period's regulatory assets disclosure to conform to the current period presentation. The deferred pipeline integrity cost previously included in "Other Regulatory Assets" was reclassified to the line item "Pipeline Integrity Cost" in the regulatory asset table disclosed in Note 4.
Equity Investments	Equity Investments - Marketable equity securities that are purchased as long-term investments are classified as Available-for-Sale Securities and carried at their fair value on our balance sheets. Any unrealized gains or losses are included in Accumulated Other Comprehensive Loss.  An impairment loss is recorded when there is clear evidence that a decline in value is other than temporary.
Estimates and Assumptions	Estimates and Assumptions - We prepare our financial statements to conform with accounting principles generally accepted in the United States of America (GAAP). Management makes estimates and assumptions that affect the amounts reported in the financial statements and related disclosures. Therefore, actual results could differ from those estimates. Significant estimates include amounts related to regulatory accounting, energy derivatives, environmental remediation costs, pension and other postretirement benefit costs, and revenue recognition.
Regulation	Regulation - We are subject to the rules and regulations of the New Jersey Board of Public Utilities (BPU). See Note 3 for a detailed discussion of our rate structure and regulatory actions. We maintain our accounts according to the BPU’s prescribed Uniform System of Accounts. We follow the accounting for regulated enterprises prescribed by the FASB ASC Topic 980 – “Regulated Operations.”  In general, Topic 980 allows for the deferral of certain costs (regulatory assets) and creation of certain obligations (regulatory liabilities) when it is probable that such items will be recovered from or refunded to customers in future periods. See Note 4 for a detailed discussion of regulatory assets and liabilities.
Operating Revenues	Operating Revenues - Gas revenues are recognized in the period the commodity is delivered to customers. For retail customers that are not billed at the end of the month, we record an estimate to recognize unbilled revenues for gas delivered from the date of the last meter reading to the end of the month.
Revenue and Throughput-Based Taxes	Revenue and Throughput-Based Taxes - SJG collects certain revenue-based energy taxes from our 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.
Accounts Receivable and Provision for Uncollectible Accounts	Accounts Receivable and Provision for Uncollectible Accounts - Accounts receivable are carried at the amount owed by customers. A provision for uncollectible accounts is established based on our collection experience and an assessment of the collectibility of specific accounts.
Natural Gas in Storage	Natural Gas in Storage – Natural Gas in Storage is reflected at average cost on the balance sheets, and represents natural gas that will be utilized in the ordinary course of business.
Property, Plant & Equipment	Property, Plant & Equipment - For regulatory purposes, utility plant is stated at original cost, which may be different than our cost if the assets were acquired from another regulated entity. The cost of adding, replacing and renewing property is charged to the appropriate plant account.
Asset Retirement Obligations	Asset Retirement Obligations - The amounts included under Asset Retirement Obligations (ARO) are primarily related to the legal obligations we have to cut and cap our gas distribution pipelines when taking those pipelines out of service in future years. These liabilities are generally recognized upon the acquisition or construction of the asset. The related asset retirement cost is capitalized concurrently by increasing the carrying amount of the related asset by the same amount as the liability. Changes in the liability are recorded for the passage of time (accretion) or for revisions to cash flows originally estimated to settle the ARO.
Depreciation	Depreciation - We depreciate utility plant on a straight-line basis over the estimated remaining lives of the various property classes. These estimates are periodically reviewed and adjusted as required after BPU approval. The composite annual rate for all depreciable utility property was approximately 2.2% in 2014, 2.3% in 2013 and 2.4% in 2012. The actual composite rate may differ from the approved rate as the asset mix changes over time. Except for retirements outside of the normal course of business, accumulated depreciation is charged with the cost of depreciable utility property retired, less salvage.
Capitalized Interest	Capitalized Interest - We capitalize interest on construction at the rate of return on rate base utilized by the BPU to set rates in our last base rate proceeding (See Note 3). Capitalized interest is included in Utility Plant on the balance sheets. Interest Charges are presented net of capitalized interest on the statements of income.  We capitalized interest of $4.4 million in 2014, $8.2 million in 2013 and $6.5 million in 2012. The decrease in 2014 is related to the CIRT projects rolling into customer rates effective October 31, 2013 . Under the CIRT, qualified capital expenditures continued to accrue interest on construction until such projects were rolled into customer rates and recovery of the expenditures commenced.All CIRT program investments have been rolled into rate base and the CIRT program is now concluded. See Note 3 for additional discussion of the CIRT programs.
Impairment of Long-Lived Assets	Impairment of Long-Lived Assets - We review the carrying amount of long-lived assets for possible impairment whenever events or changes in circumstances indicate that such amounts may not be recoverable. For the years ended 2014, 2013 and 2012, no significant impairments were identified.
Derivative Instruments	Derivative Instruments - SJG, through its affiliate, South Jersey Resources Group (SJRG) and another counterparty, uses a variety of derivative instruments to limit its exposure to market risk in accordance with strict guidelines (See Note 14).  These contracts, which 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 balance sheets.  The costs or benefits of these short-term contracts are recoverable through SJG’s Basic Gas Supply Service (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 balance sheets.
	SJG 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 balance sheets.  The fair value represents the amount SJG would have to pay the counterparty to terminate these contracts as of those dates.  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 Other Regulatory Assets in the balance sheets.
Income Taxes	Income Taxes - Deferred income taxes are provided for all significant temporary differences between the book and taxable basis of assets and liabilities in accordance with FASB ASC Topic 740 – “Income Taxes” (See Note 6). A valuation allowance is established when it is determined that it is more likely than not that a deferred tax asset will not be realized.
Cash and Cash Equivalents	Cash and Cash Equivalents - For purposes of reporting cash flows, highly liquid investments with original maturities of three months or less are considered cash equivalents.
NEW ACCOUNTING PRONOUNCEMENTS	NEW ACCOUNTING PRONOUNCEMENTS - Other than as described below, no new accounting pronouncement issued or effective during 2014, 2013 or 2012 had, or is expected to have, a material impact on the financial statements.
	In July 2013, the FASB issued ASU 2013-11, Balance Sheet Presentation of an Unrecognized Income Tax Benefit for a Net Operating Loss or Tax Credit Carryforward. This ASU provides that a liability related to an unrecognized tax benefit should be offset against a deferred tax asset for a net operating loss carryforward, a similar tax loss, or a tax credit carryforward if such settlement is required or expected in the event the uncertain tax position is disallowed. The new guidance is effective for fiscal years, and interim periods within those years, beginning after December 15, 2013. The adoption of this guidance did not have an impact on the Company's financial statement results.
	In May 2014, the 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 services 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. The Company does not expect this standard to have an impact on its financial statements upon adoption.
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.

SUMMARY_OF_SIGNIFICANT_ACCOUNT2

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)	12 Months Ended
	Dec. 31, 2014
Accounting Policies [Abstract]
Schedule of Utility Plant balances	Utility Plant balances as of December 31, 2014 and 2013 were comprised of the following (in thousands):
		2014			2013
	Utility Plant:
	Production Plant	$	296		$	296
	Storage Plant	23,023			22,538
	Transmission Plant	248,737			248,074
	Distribution Plant	1,547,218			1,417,939
	General Plant	103,604			53,162
	Other Plant	1,855			1,855
	Utility Plant in Service	1,924,733			1,743,864
	Construction Work in Progress	78,233			72,940
	Total Utility Plant	$	2,002,966		$	1,816,804
Asset retirement obligation activity	ARO activity during 2014 and 2013 was as follows (in thousands):
		2014			2013
	ARO as of January 1,	$	41,178		$	38,892
	Accretion	1,595			1,514
	Additions	664			743
	Settlements	(1,461		)	(1,630		)
	Revisions in Estimated Cash Flows *	—			1,659
	ARO as of December 31,	$	41,976		$	41,178
	* The revision in estimated cash flows in 2013 reflects an increase in the inflation rate used to determine the ARO settlement amount.

STOCKBASED_COMPENSATION_PLANS_

STOCK-BASED COMPENSATION PLANS (Tables)	12 Months Ended
	Dec. 31, 2014
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 December 31, 2014, 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		4,001		$	44.38	21.1	%	0.4	%
	Jan. 2013 - EPS		4,001		$	51.18	n/a		n/a
	Jan. 2014 - TSR		5,197		$	42.62	20	%	0.8	%
	Jan. 2014 - EPS		5,197		$	54.44	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 2014, excluding accrued dividend equivalents:
		Shares		Weighted
				Average
				Grant Date
				Fair Value
	Nonvested Shares Outstanding, January 1, 2014	15,068		$	50.73
	Granted	10,394		$	48.53
	Vested*	(7,065	)	$	54.08
	Nonvested Shares Outstanding, December 31, 2014	18,397		$	48.2
	* Performance targets during the three-year vesting period were not attained for the January 2012 grant. As a result, no shares will be awarded in 2015.

REGULATORY_ASSETS_AND_LIABILIT1

REGULATORY ASSETS AND LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2014
Regulatory Assets and Liabilities Disclosure [Abstract]
Schedule of Regulatory Assets	Regulatory Assets at December 31st consisted of the following items (in thousands):
		2014		2013
	Environmental Remediation Costs:
	Expended - Net	$	29,540	$	29,945
	Liability for Future Expenditures	124,308		119,492
	Deferred Asset Retirement Obligation Costs	31,584		31,142
	Deferred Pension and Other Postretirement Benefit Costs	99,040		59,284
	Deferred Gas Costs - Net	32,202		—
	Conservation Incentive Program - Receivable	—		10,526
	Societal Benefit Costs Receivable	385		10,408
	Premium for Early Retirement of Debt	—		955
	Deferred Interest Rate Contracts	7,325		3,735
	Energy Efficiency Tracker	11,247		10,420
	Pipeline Supplier Service Charges	5,441		7,106
	Pipeline Integrity Cost	3,431		2,902
	AFUDC - Equity Related Deferrals	10,781		7,810
	Other Regulatory Assets	1,876		2,356
	Total Regulatory Assets	$	357,160	$	296,081
Schedule of Regulatory Liabilities	Regulatory Liabilities at December 31 consisted of the following items (in thousands):
		2014		2013
	Excess Plant Removal Costs	$	35,940	$	40,029
	Deferred Revenue - Net	—		19,067
	Conservation Incentive Program - Payable	4,700		—
	Other Regulatory Liabilities	1,259		1,853
	Total Regulatory Liabilities	$	41,899	$	60,949

RELATED_PARTY_TRANSACTIONS_Tab

RELATED PARTY TRANSACTIONS (Tables)	12 Months Ended
	Dec. 31, 2014
Related Party Transactions [Abstract]
Summary of related party transactions	A summary of these related party transactions, excluding pass-through items, included in Operating Revenues were as follows (in thousands):
		2014			2013			2012
	Operating Revenues/Affiliates:
	SJRG	$	959		$	1,390		$	884
	Marina	1,083			1,297			841
	Other	—			2			10
	Total Operating Revenues/Affiliates	$	2,042		$	2,689		$	1,735
	Related party transactions, excluding pass-through items, included in Operating Expenses were as follows (in thousands):
		2014			2013			2012
	Costs of Sales/Affiliates
	(Excluding depreciation):
	SJRG	$	15,265		$	14,959		$	9,083
	Derivative (Gains)/Losses (See Note 1):
	SJRG	$	(1,582	)	$	887		$	15,407
	Operations Expense/Affiliates:
	SJI	$	14,110		$	11,990		$	10,870
	SJIS	—			5,531			5,397
	Millennium	2,668			2,686			3,149
	Other	(434		)	(428		)	(500		)
	Total Operations Expense/Affiliates	$	16,344		$	19,779		$	18,916

INCOME_TAXES_AND_CREDITS_Table

INCOME TAXES AND CREDITS (Tables)	12 Months Ended
	Dec. 31, 2014
Income Tax Disclosure [Abstract]
Schedule of effective income tax rate reconciliation	Total income taxes applicable to operations differ from the tax that would have resulted by applying the statutory Federal income tax rate to pre-tax income for the following reasons (in thousands):
		2014			2013			2012
	Tax at Statutory Rate	$	35,482		$	33,974		$	32,183
	Increase (Decrease) Resulting from:
	State Income Taxes	1,935			4,833			5,302
	Amortization of Investment Tax Credits	(211		)	(258		)	(287		)
	ESOP Dividend	(1,109		)	(1,058		)	(1,027		)
	AFUDC	(1,481		)	(916		)	(1,048		)
	Other - Net	279			(1,742		)	(1,412		)
	Net Income Taxes	$	34,895		$	34,833		$	33,711
Schedule of components of provision for income taxes	The provision for Income Taxes is comprised of the following (in thousands):
		2014			2013			2012
	Current:
	Federal	$	60		$	(53	)	$	(4,635	)
	State	2,642			2,946			(7		)
	Total Current	2,702			2,893			(4,642		)
	Deferred:
	Federal	32,069			27,707			30,477
	State	335			4,491			8,163
	Total Deferred	32,404			32,198			38,640
	Investment Tax Credits	(211		)	(258		)	(287		)
	Net Income Taxes	$	34,895		$	34,833		$	33,711
Schedule of deferred tax assets and liabilities	The net tax effect of temporary differences between the carrying amounts of assets and liabilities for financial reporting and income tax purposes resulted in the following net deferred tax liabilities at December 31 (in thousands):
		2014			2013
	Current:
	Net Operating Loss Carryforward	$	(40,573	)	$	(27,600	)
	Budget Billing - Customer Accounts	1,138			1,152
	Provision for Uncollectibles	(2,676		)	(1,726		)
	Conservation Incentive Program	(2,027		)	4,631
	Section 461 Prepayments	1,026			1,156
	Other	(952		)	(922		)
	Current Deferred Tax Asset - Net	$	(44,064	)	$	(23,309	)
	Noncurrent:
	Book Versus Tax Basis of Property	$	417,178		$	371,684
	Deferred Fuel Costs - Net	22,959			1,330
	Environmental Remediation	13,500			14,392
	Deferred Regulatory Costs	6,333			13,665
	Deferred State Tax	(17,390		)	(15,471		)
	Investment Tax Credit Basis Gross-Up	(77		)	(185		)
	Deferred Pension & Other Post Retirement Benefits	39,891			24,218
	Pension & Other Post Retirement Benefits	(27,782		)	(14,152		)
	Deferred Revenues	(11,452		)	(9,266		)
	Net Operating Loss Carryforward	(12,887		)	(8,764		)
	Other	4,749			3,524
	Noncurrent Deferred Tax Liability – Net	$	435,022		$	380,975
Reconciliation of unrecognized tax benefits	A reconciliation of unrecognized tax benefits is as follows (in thousands):
		2014			2013			2012
	Balance at January 1,	$	547		$	503		$	421
	Increase as a result of tax position taken in prior years	5			44			82
	Decrease due to a lapse in the statue of limitations	—			—			—
	Settlements	—			—			—
	Balance at December 31,	$	552		$	547		$	503

LONGTERM_DEBT_Tables

LONG-TERM DEBT (Tables)	12 Months Ended
	Dec. 31, 2014
Debt Disclosure [Abstract]
Schedule of long-term debt	A schedule of our long-term debt as of December 31, including current maturities, is as follows (in thousands):
				2014			2013
	Long-Term Debt (A):
	First Mortgage Bonds: (B)
	4.52	%	Series due 2014 (C)	—			11,000
	5.115	%	Series due 2014 (D)	—			10,000
	5.387	%	Series due 2015	10,000			10,000
	5.437	%	Series due 2016	10,000			10,000
	4.6	%	Series due 2016	17,000			17,000
	4.657	%	Series due 2017	15,000			15,000
	7.97	%	Series due 2018	10,000			10,000
	7.125	%	Series due 2018	20,000			20,000
	5.587	%	Series due 2019	10,000			10,000
	3	%	Series due 2024	50,000			50,000
	3.03	%	Series due 2024	35,000			35,000
	3.63	%	Series due 2025	10,000			10,000
	4.84	%	Series due 2026	15,000			15,000
	4.93	%	Series due 2026	45,000			45,000
	4.03	%	Series due 2027	45,000			45,000
	4.01	%	Series due 2030 (E)	50,000			50,000
	4.23	%	Series due 2030 (F)	30,000			—
	3.74	%	Series due 2032	35,000			35,000
	5.55	%	Series due 2033	32,000			32,000
	6.213	%	Series due 2034	10,000			10,000
	5.45	%	Series due 2035	10,000			10,000
	Series A 2006 Tax-Exempt First Mortgage Bonds
	Variable Rate, due 2036 (G)			25,000			25,000
	Variable Rate Bank Term Facility, due 2017 (H)			59,000			—
	Total Long-Term Debt Outstanding			543,000			475,000
	Less Current Maturities (A) (G)			(35,909		)	(21,000		)
	Long-Term Debt			$	507,091		$	454,000
	(A)	Long-term debt maturities and sinking funds requirements for the succeeding five years are as follows (in thousands): 2015, $35,909; 2016, $27,909; 2017, $74,909; 2018, $38,909; 2019, $18,909.
	(B)	Our First Mortgage dated October 1, 1947, as supplemented, securing the First Mortgage Bonds constitutes a direct first mortgage lien on substantially all utility plant.
	(C)	In July 2014, SJG retired $11.0 million aggregate principal amount of 4.52% Medium Term Notes (MTN's) at maturity.
	(D)	In September 2014, SJG retired $10.0 million aggregate principal amount of 5.115% MTN's at maturity.
	(E)	In November 2013, SJG issued $50.0 million aggregate principal amount of 4.01% MTN's due November 2030.
	(F)	In January 2014, SJG issued $30.0 million aggregate principal amount of 4.23% MTN's due January 2030.
	(G)	These variable rate demand bonds bear interest at a floating rate that resets weekly. The interest rate as of December 31, 2014 was 0.08%. Liquidity support on these bonds is provided under a separate letter of credit facility that expires in August, 2015; as such, these bonds have been included in the current portion of long-term debt. These bonds contain no financial covenants.
	(H)	In June 2014, SJG entered into a $200.0 million multiple-draw term facility offered by a syndicate of banks which expires in June 2017. SJG can draw under this facility through June 2016 and this facility bears interest at a floating rate based on LIBOR plus a spread determined by SJG's credit ratings. As of December 31, 2014, SJG had borrowed an aggregate $59.0 million under this facility and the proceeds were used to pay down short-term debt.

LINES_OF_CREDIT_Tables

LINES OF CREDIT (Tables)	12 Months Ended
	Dec. 31, 2014
Line of Credit Facility [Abstract]
Schedule of lines of credit	Credit facilities and available liquidity as of December 31, 2014 were as follows (in thousands):
		Total Facility		Usage		Available Liquidity		Expiration Date
	Commercial Paper Program/ Revolving Credit Facility	$	200,000	$	101,400	$	98,600	May-18
	Uncommitted Bank Lines	10,000		—		10,000		Aug-15
	Total	$	210,000	$	101,400	$	108,600

PENSION_AND_OTHER_POSTRETIREME1

PENSION AND OTHER POSTRETIREMENT BENEFITS (Tables)	12 Months Ended
	Dec. 31, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Net Benefit Costs	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											Other Postretirement Benefits
		2014				2013				2012			2014				2013			2012
	Service Cost	$	3,697			$	4,487			$	3,718		$	585			$	771		$	704
	Interest Cost	8,952				7,886				8,008			2,297				2,221			2,443
	Expected Return on Plan Assets	(10,818		)		(9,435		)		(8,249		)	(2,467		)		(2,158		)	(1,910		)
	Amortization:
	Prior Service Cost (Credits)	177				208				207			133				(195		)	(195		)
	Actuarial Loss	4,864				7,608				6,432			770				1,555			1,534
	Net Periodic Benefit Cost	6,872				10,754				10,116			1,318				2,194			2,576
	Capitalized Benefit Costs	(3,047		)		(5,002		)		(4,684		)	(722		)		(1,172		)	(1,340		)
	Affiliate SERP Allocations	(1,313		)		(1,389		)		(1,107		)	—				—			—
	Total Net Periodic Benefit Expense	$	2,512			$	4,363			$	4,325		$	596			$	1,022		$	1,236
Schedule Defined Benefit Plans, Changes in Regulatory Assets and Accumulated Other Comprehensive Income (Loss)	Details of the activity within the Regulatory Asset and Accumulated Other Comprehensive Loss associated with Pension and Other Postretirement Benefits are as follows (in thousands):
		Regulatory Assets								Accumulated Other Comprehensive Loss (pre-tax)
		Pension Benefits				Other Postretirement Benefits				Pension Benefits			Other Postretirement Benefits
	Balance at January 1, 2013	$	68,713			$	27,184			$	21,908		$	—
	Amounts Arising during the Period:
	Net Actuarial Loss	(20,554		)		(9,171		)		(1,576		)	—
	Amounts Amortized to Net Periodic Costs:
	Net Actuarial Loss	(5,319		)		(1,555		)		(2,289		)	—
	Prior Service (Cost) Credit	(208		)		194				—			—
	Balance at December 31, 2013	42,632				16,652				18,043			—
	Amounts Arising during the Period:
	Net Actuarial Loss	31,075				7,826				7,102			—
	Prior Service Cost (Credit)	486				4,146				—
	Amounts Amortized to Net Periodic Costs:
	Net Actuarial Loss	(2,841		)		(628		)		(1,975		)	—
	Prior Service (Cost) Credit	(175		)		(133		)		—			—
	Balance at December 31, 2014	$	71,177			$	27,863			$	23,170		$	—
Schedule of Amounts in Regulatory Assets to be Recognized over Next Fiscal Year	The estimated costs that will be amortized from Regulatory Assets into net periodic benefit costs in 2014 are as follows (in thousands):
		Pension Benefits				Other Postretirement Benefits
	Prior Service Costs	$	199			$	499
	Net Actuarial Loss	$	5,922			$	1,235
Schedule of Amounts in Accumulated Other Comprehensive Income (Loss) to be Recognized over Next Fiscal Year	The estimated costs that will be amortized from Accumulated Other Comprehensive Loss into net periodic benefit costs in 2015 are as follows (in thousands):
		Pension Benefits				Other Postretirement Benefits
	Net Actuarial Loss	$	2,750			$	—
Schedule of Net Funded Status and Amounts Recognized in Balance Sheet	A reconciliation of the plans’ benefit obligations, fair value of plan assets, funded status and amounts recognized in our balance sheets follows (in thousands):
										Other
		Pension Benefits								Postretirement Benefits
		2014				2013				2014			2013
	Change in Benefit Obligations:
	Benefit Obligation at Beginning of Year	$	180,668			$	186,899			$	50,915		$	55,615
	Service Cost	3,697				4,487				585			771
	Interest Cost	8,952				7,886				2,297			2,221
	Actuarial (Gain) Loss	35,634				(11,514		)		6,008			(4,552		)
	Retiree Contributions	—				—				452			335
	Plan Amendments	534				—				4,146			—
	Benefits Paid	(7,880		)		(7,090		)		(3,733		)	(3,475		)
	Benefit Obligation at End of Year	$	221,605			$	180,668			$	60,670		$	50,915
	Change in Plan Assets:
	Fair Value of Plan Assets at Beginning of Year	$	142,674			$	119,391			$	39,471		$	32,694
	Actual Return on Plan Assets	8,275				20,049				507			5,101
	Employer Contributions	1,499				10,324				4,254			4,816
	Retiree Contributions	—				—				452			335
	Benefits Paid	(7,880		)		(7,090		)		(3,733		)	(3,475		)
	Fair Value of Plan Assets at End of Year	$	144,568			$	142,674			$	40,951		$	39,471
	Funded Status at End of Year:
	Accrued  Net Benefit Cost at End of Year	$	(77,037	)		$	(37,994	)		$	(19,719	)	$	(11,444	)
	Amounts Recognized in the Statement of Financial Position Consist of:
	Current Liabilities	$	(1,515	)		$	(1,241	)		$	—		$	—
	Noncurrent Liabilities	(75,522		)		(36,753		)		(19,719		)	(11,444		)
	Net Amount Recognized at End of Year	$	(77,037	)		$	(37,994	)		$	(19,719	)	$	(11,444	)
	Amounts Recognized in Regulatory Assets Consist of:
	Prior Service Costs	$	944			$	634			$	4,965		$	952
	Net Actuarial Loss	70,233				41,998				22,898			15,700
	Net Amount Recognized at End of Year	$	71,177			$	42,632			$	27,863		$	16,652
	Amounts Recognized in Accumulated Other Comprehensive Loss Consist of:
	Net Actuarial Loss	$	23,170			$	18,043			$	—		$	—
Schedule of Assumptions Used	The weighted-average assumptions used to determine benefit obligations at December 31 were:
		Pension Benefits						Other Postretirement Benefits
		2014			2013			2014			2013
	Discount Rate	4.25	%		5.09	%		4.2	%		4.91	%
	Rate of Compensation Increase	3.5	%		3.5	%		3.5	%		3.5	%
	The weighted-average assumptions used to determine net periodic benefit cost for years ended December 31 were:
		Pension Benefits									Other Postretirement Benefits
		2014			2013			2012			2014		2013			2012
	Discount Rate	5.09	%		4.26	%		5.03	%		4.91	%	4.14	%		4.92	%
	Expected Long-Term Return on Plan Assets	7.75	%		7.5	%		7.5	%		6.25	%	6.6	%		6.6	%
	Rate of Compensation Increase	3.5	%		3.25	%		3.25	%		3.5	%	3.25	%		3.25	%
Schedule of Health Care Cost Trend Rates	The assumed health care cost trend rates at December 31 were:
		2014			2013
	Medical Care and Drug Cost Trend Rate Assumed for Next Year	7	%		7	%
	Dental Care Cost Trend Rate Assumed for Next Year	4.75	%		4.75	%
	Rate to which Cost Trend Rates are Assumed to Decline (the Ultimate Trend Rate)	4.75	%		4.75	%
	Year that the Rate Reaches the Ultimate Trend Rate	2023			2023
Schedule of Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates	A one-percentage-point change in assumed health care cost trend rates would have the following effects (in thousands):
		1-Percentage-				1-Percentage-
		Point Increase				Point Decrease
	Effect on the Total of Service and Interest Cost	$	112			$	(94	)
	Effect on Postretirement Benefit Obligation	$	3,806			$	(3,065	)
Schedule of Effect of Significant Unobservable Inputs, Changes in Plan Assets	Fair Value Measurement Using Significant
	Unobservable Inputs (Level 3)
	(In thousands)
		Guaranteed				Hedge				Private			Real				Total
		Insurance				Funds				Equity			Estate
		Contract								Funds
	Balance at January 1, 2013	$	9,898			$	—			$	2,557		$	4,778			$	17,233
	Actual return on plan assets:
	Relating to assets still held at the reporting date	(68		)		124				80			623				759
	Relating to assets sold during the period	14				—				345			—				359
	Purchases, Sales and Settlements	(773		)		3,204				(542		)	—				1,889
	Balance at December 31, 2013	$	9,071			$	3,328			$	2,440		$	5,401			$	20,240
	Actual return on plan assets:
	Relating to assets still held at the reporting date	396				141				(20		)	586				1,103
	Relating to assets sold during the period	10				—				260			—				270
	Purchases, Sales and Settlements	(739		)		—				215			—				(524		)
	Balance at December 31, 2014	$	8,738			$	3,469			$	2,895		$	5,987			$	21,089
Schedule of Expected Benefit Payments	Future Benefit Payments - The following benefit payments, which reflect expected future service, as appropriate, are expected to be paid during the following years (in thousands):
		Pension Benefits				Other
						Postretirement Benefits
	2015	$	8,444			$	3,999
	2016	$	8,886			$	4,199
	2017	$	9,143			$	4,222
	2018	$	10,263			$	4,285
	2019	$	11,174			$	4,389
	2020 - 2024	$	65,205			$	23,421
Pension Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Allocation of Plan Assets	The fair values of SJG’s pension plan assets at December 31, 2014 and 2013 by asset category are as follows (in thousands):
	Asset Category	Total				Level 1				Level 2			Level 3
	As of December 31, 2014:
	Cash / Cash Equivalents:
	Common/Collective Trust Funds (a)	$	554			$	—			$	554		$	—
	STIF-Type Instrument (b)	1,003				—				1,003			—
	Equity securities:
	Common/Collective Trust Funds – U.S. (a)	41,000				—				41,000			—
	Common/Collective Trust Funds – International (a)	24,796				—				24,796			—
	U.S. Large-Cap (c)	10,380				10,380				—			—
	U.S. Mid-Cap (c)	4,122				4,122				—			—
	U.S. Small-Cap (c)	186				186				—
	International (c)	2,698				2,698				—			—
	Fixed Income:
	Common/Collective Trust Funds (a)	38,740				—				38,740			—
	Guaranteed Insurance Contract (d)	8,738				—				—			8,738
	Hedge Funds (e)	3,469				—				—			3,469
	Other types of investments:
	Private Equity Fund (f)	2,895				—				—			2,895
	Common/Collective Trust Fund – Real Estate (g)	5,987				—				—			5,987
	Total	$	144,568			$	17,386			$	106,093		$	21,089
	Asset Category	Total				Level 1				Level 2			Level 3
	As of December 31, 2013:
	Cash / Cash Equivalents:
	Common/Collective Trust Funds (a)	$	334			$	—			$	334		$	—
	STIF-Type Instrument (b)	943				—				943			—
	Equity securities:
	Common/Collective Trust Funds – U.S. (a)	41,527				—				41,527			—
	Common/Collective Trust Funds – International (a)	27,312				—				27,312			—
	U.S. Large-Cap (c)	9,342				9,342				—			—
	U.S. Mid-Cap (c)	3,313				3,313				—			—
	International (c)	2,935				2,935				—			—
	Fixed Income:
	Common/Collective Trust Funds (a)	36,728				—				36,728			—
	Guaranteed Insurance Contract (d)	9,071				—				—			9,071
	Hedge Funds (e)	3,328				—				—			3,328
	Other types of investments:												—
	Private Equity Fund (f)	2,440				—				—			2,440
	Common/Collective Trust Fund – Real Estate (g)	5,401				—				—			5,401
	Total	$	142,674			$	15,590			$	106,844		$	20,240
	(a)	This category represents common/collective trust fund investments through a commingled employee benefit trust (excluding real estate).  These commingled funds are not traded publicly; however, the majority of the underlying assets held in these funds are stocks and bonds that are traded on active markets and prices for these assets are readily observable.  Also included in these funds are interest rate swaps, asset backed securities, mortgage backed securities and other investments with observable market values. Holdings in these commingled funds are classified as Level 2 investments.
	(b)	This category represents short-term investment funds held for the purpose of funding disbursement payment arrangements.  Underlying assets are valued based on quoted prices in active markets, or where quoted prices are not available, based on models using observable market information.  Since not all values can be obtained from quoted prices in active markets, these funds are classified as Level 2 investments.
	(c)	This category of equity investments represents a managed portfolio of common stock investments in five sectors: telecommunications, electric utilities, gas utilities, water and energy.  These common stocks are actively traded on exchanges and price quotes for these shares are readily available.  These common stocks are classified as Level 1 investments.
	(d)	This category represents SJI’s Group Annuity contracts with a nationally recognized life insurance company.  The contracts are the assets of the plan, while the underlying assets of the contracts are owned by the contract holder.  Valuation is based on a formula and calculation specified within the contract.  Since the valuation is based on the reporting entity’s own assumptions, these contracts are classified as Level 3 investments.
	(e)	This category represents a collection of underlying funds which are all domiciled outside of the United States. All of the underlying fund managers are based in the U.S.; however, they do not necessarily trade only in the U.S. markets. The fair value of these funds is determined by the underlying fund's general partner or manager. These funds are classified as Level 3 investments.
	(f)	This category represents a limited partnership which includes several investments in U.S. leveraged buyout, venture capital, and special situation funds.  Fund valuations are reported on a 90 day lag and, therefore, the value reported herein represents the market value as of September 30, 2014 and 2013, respectively.  The fund’s investments are stated at fair value, which is generally based on the valuations provided by the general partners or managers of such investments.  Fund investments are illiquid and resale is restricted.  These funds are classified as Level 3 investments.
	(g)	This category represents real estate common/collective trust fund investments through a commingled employee benefit trust. These commingled funds are part of a direct investment in a pool of real estate properties. These funds are valued by investment managers on a periodic basis using pricing models that use independent appraisals from sources with professional qualifications. Since these valuation inputs are not highly observable, the real estate funds are classified as Level 2 investments.
Other Postretirement Benefits [Member]
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Schedule of Allocation of Plan Assets	The fair values of SJG’s other postretirement benefit plan assets at December 31, 2014 and 2013 by asset category are as follows (in thousands):
	Asset Category	Total				Level 1				Level 2			Level 3
	As of December 31, 2014:
	Cash	$	142			$	142			$	—		$	—
	Equity Securities:
	Common/Collective Trust Funds - U.S. (a)	10,006				—				10,006			$	—
	Common/Collective Trust Funds - International (a)	7,030				—				7,030			—
	Mutual Fund - U.S. (b)	4,447				4,447				—			—
	Mutual Funds - International (b)	1,671				1,671				—			—
	Fixed Income:
	Common/Collective Trust Funds - Bonds (a)	11,059				—				11,059			—
	Mutual Funds - Bonds (b)	2,624				2,624				—			—
	Other Types of Investments:
	Mutual Funds - REITS (b)	286				286				—			—
	Company Owned Life Insurance (c)	3,686				—				3,686			—
	Total	$	40,951			$	9,170			$	31,781		$	—
	Asset Category	Total				Level 1				Level 2			Level 3
	As of December 31, 2013:
	Equity Securities:
	Common/Collective Trust Funds - U.S. (a)	$	12,412			$	—			$	12,412		$	—
	Common/Collective Trust Funds - International (a)	10,031				—				10,031			—
	Mutual Fund - U.S. (b)	2,814				2,814				—			—
	Fixed Income:
	Common/Collective Trust Funds - Bonds (a)	14,214				—				14,214			—
	Total	$	39,471			$	2,814			$	36,657		$	—
	(a)	This category represents common/collective trust fund investments through a commingled employee benefit trust (excluding real estate).  These commingled funds are not traded publicly; however, the majority of the underlying assets held in these funds are stocks and bonds that are traded on active markets and prices for these assets are readily observable.  Also included in these funds are interest rate swaps, asset backed securities, mortgage backed securities and other investments with observable market values. Holdings in these commingled funds are classified as Level 2 investments.
	(b)	This category represents mutual fund investments. The mutual funds are actively traded on exchanges and price quotes for the shares are readily available. These mutual funds are classified as Level 1 investments.
	(c)	This category represents Company-owned life insurance policies with a nationally known life insurance company. The value of these policies is backed by a series of common/collective trust funds held by the insurance carrier similar to category (a) above. Holdings in these insurance policies are classified as Level 2 investments.

COMMITMENTS_AND_CONTINGENCIES_

COMMITMENTS AND CONTINGENCIES (Tables)	12 Months Ended
	Dec. 31, 2014
Commitments and Contingencies Disclosure [Abstract]
Schedule of Environmental Loss Contingencies	The following table details the amounts accrued and expended for environmental remediation at December 31 (in thousands):
		2014			2013
	Beginning of Year	$	119,492		$	107,410
	Accruals	16,453			22,264
	Expenditures	(11,637		)	(10,182		)
	End of Year	$	124,308		$	119,492

FAIR_VALUE_OF_FINANCIAL_ASSETS1

FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES (Tables)	12 Months Ended
	Dec. 31, 2014
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 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	$	—
	As of December 31, 2013
		Total		Level 1		Level 2		Level 3
	Assets
	Available-for-Sale Securities (A)	$	8,696	$	8,696	$	—	$	—
	Derivatives – Energy Related Assets (B)	1,500		1,409		91		—
		$	10,196	$	10,105	$	91	$	—
	Liabilities
	Derivatives – Energy Related Liabilities (B)	$	759	$	155	$	604	$	—
	Derivatives – Other (C)	3,735		—		3,735		—
		$	4,494	$	155	$	4,339	$	—
	(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)	12 Months Ended
	Dec. 31, 2014
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of notional amounts of outstanding derivative positions	As of December 31, 2014, SJG’s active interest rate swaps were as follows:
	Notional Amount				Fixed Interest Rate			Start Date	Maturity		Type of Debt		Obligor
	$	12,500,000			3.43	%		12/1/06	2/1/36		Tax-exempt		SJG
	$	12,500,000			3.43	%		12/1/06	2/1/36		Tax-exempt		SJG
Fair value of derivative instruments	The fair values of all derivative instruments, as reflected in the balance sheets as of December 31, 2014 and December 31, 2013, are as follows (in thousands):
	Derivatives not designated as hedging instruments under GAAP		2014							2013
			Assets				Liabilities			Assets				Liabilities
	Energy related commodity contracts:
	Derivatives – Energy Related – Current		$	2,051			$	6,305		$	1,222			$	711
	Derivatives – Energy Related – Non-Current		—				1,298			278				48
	Interest rate contracts:
	Derivatives – Other		—				7,325			—				3,735
	Total derivatives not designated as hedging instruments under GAAP		$	2,051			$	14,928		$	1,500			$	4,494
Offsetting arrangements	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 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		)
	As of December 31, 2013
	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		$	1,500			$	—		$	1,500			$	(155	)	(A)	$	(498	)	$	847
	Derivatives - Energy Related Liabilities		(759		)		—			(759		)		155			(B)	—			(604		)
	Derivatives - Other		(3,735		)		—			(3,735		)		—				—			(3,735		)
	(A) The balances at December 31, 2014 and December 31, 2013 were related to derivative liabilities which can be net settled against derivative assets.
	(B) The balances at December 31, 2014 and December 31, 2013 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 statements of income for 2014 , 2013 and 2012 are as follows (in thousands):
		Year ended December 31,
	Derivatives in Cash Flow Hedging Relationships	2014				2013			2012
	Interest Rate Contracts:
	Losses reclassified from accumulated OCI into income (a)	$	(46	)		$	(46	)	$	(46	)
	(a) Included in Interest Charges

ACCUMULATED_OTHER_COMPREHENSIV1

ACCUMULATED OTHER COMPREHENSIVE LOSS (AOCL) (Tables)	12 Months Ended
	Dec. 31, 2014
Equity [Abstract]
Schedule of changes in accumulated other comprehensive loss (AOCL)	The following tables summarizes the changes in accumulated other comprehensive loss (AOCL) for the years ended December 31, 2014 and 2013, respectively (in thousands):
		Postretirement Liability Adjustment				Unrealized Gain (Loss) on Derivatives-Other				Unrealized Gain (Loss) on Available-for-Sale Securities			Total
	Balance at January 1, 2014 (a)	(10,672		)		(594		)		$	397		$	(10,869	)
	Other comprehensive income before reclassifications	(4,345		)		—				76			(4,269		)
	Amounts reclassified from AOCL (b)	1,180				27				(548		)	659
	Net current period other comprehensive income	(3,165		)		27				(472		)	(3,610		)
	Balance at December 31, 2014 (a)	$	(13,837	)		$	(567	)		$	(75	)	$	(14,479	)
		Postretirement Liability Adjustment				Unrealized Gain (Loss) on Derivatives-Other				Unrealized Gain (Loss) on Available-for-Sale Securities			Total
	Balance at January 1, 2013 (a)	$	(12,958	)		$	(621	)		$	294		$	(13,285	)
	Other comprehensive income before reclassifications	932				—				592			1,524
	Amounts reclassified from AOCL (b)	1,354				27				(489		)	892
	Net current period other comprehensive income	2,286				27				103			2,416
	Balance at December 31, 2013 (a)	$	(10,672	)		$	(594	)		$	397		$	(10,869	)
	(a) Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.
	(b) See table below.
Reclassifications out of AOCL	The reclassifications out of AOCL for the years ended December 31, 2014 and 2013 is as follows (in thousands):
	Components of AOCL	Amounts Reclassified from AOCL							Affected Line Item in the Statements of Income
		For the Year Ended December 31, 2014			For the Year Ended December 31, 2013
	Unrealized Loss on Derivatives-Other - Interest Rate Contracts designated as cash flow hedges	$	46		$	46			Interest Charges
	Unrealized Gain on Available-for-Sale Securities	(918		)	(828		)		Other Income & Expense
	Actuarial Loss on Postretirement Benefits	1,975			2,289				Operating Expenses: Operations
		1,103			1,507				Loss (Income) Before Income Taxes
	Income Taxes (a)	444			615				Income Taxes (a)
	Losses (Gains) from reclassifications for the period net of tax	$	659		$	892
	(a) Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.

QUARTERLY_RESULTS_OF_OPERATION1

QUARTERLY RESULTS OF OPERATIONS - UNAUDITED (Tables)	12 Months Ended
	Dec. 31, 2014
Quarterly Financial Information Disclosure [Abstract]
Schedule of Quarterly Financial Information	The summarized quarterly results of our operations are as follows (in thousands):
		2014 Quarter Ended								2013 Quarter Ended
		31-Mar		30-Jun		Sept. 30		Dec. 31		31-Mar		30-Jun		Sept. 30		Dec. 31
	Operating Revenues	$	210,545	$	69,159	$	60,952	$	161,219	$	174,098	$	66,536	$	59,674	$	146,172
	Expenses:
	Cost of Sales (excluding depreciation)	103,293		24,879		23,400		79,644		77,602		26,108		24,717		71,654
	Operations and Maintenance
	Including Fixed Charges	46,969		38,737		37,432		47,943		38,659		33,871		33,249		39,486
	Income Taxes	22,527		2,379		534		9,455		20,771		2,269		471		11,322
	Energy and Other Taxes	1,185		830		798		947		3,003		1,277		1,052		2,530
	Total Expenses	173,974		66,825		62,164		137,989		140,035		63,525		59,489		124,992
	Other Income and Expense	1,086		1,477		2,186		811		1,450		810		764		773
	Net Income	$	37,657	$	3,811	$	974	$	24,041	$	35,513	$	3,821	$	949	$	21,953

SUMMARY_OF_SIGNIFICANT_ACCOUNT3

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details) (USD $)	0 Months Ended	1 Months Ended	12 Months Ended					24 Months Ended
	Oct. 01, 2014	Sep. 30, 2014	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2013
Accounting Policies [Abstract]
Equity investment impairments			$0		$0		$0
PUA included in both utility revenue and cost of sales			1,100,000		1,200,000		900,000
TEFA included in both utility revenue and cost of sales					4,000,000		5,100,000
Utility Plant:
Production Plant			296,000		296,000			296,000
Storage Plant			23,023,000		22,538,000			22,538,000
Transmission Plant			248,737,000		248,074,000			248,074,000
Distribution Plant			1,547,218,000		1,417,939,000			1,417,939,000
General Plant			103,604,000		53,162,000			53,162,000
Other Plant			1,855,000		1,855,000			1,855,000
Utility Plant in Service			1,924,733,000		1,743,864,000			1,743,864,000
Construction Work in Progress			78,233,000		72,940,000			72,940,000
Total Utility Plant			2,002,966,000		1,816,804,000			1,816,804,000
Asset Retirement Obligation, Roll Forward Analysis [Roll Forward]
ARO as of January 1,			41,178,000		38,892,000
Accretion			1,595,000		1,514,000
Additions			664,000		743,000
Settlements			-1,461,000		-1,630,000
Revisions in Estimated Cash Flows			0	[1]	1,659,000	[1]
ARO as of December 31,			41,976,000		41,178,000		38,892,000	41,178,000
Composite annual rate for all depreciable utility property			2.20%		2.30%		2.40%
Public Utilities, Depreciate Rate	2.10%	2.10%						2.40%
Interest capitalized			$4,400,000		$8,200,000		$6,500,000
[1]	The revision in estimated cash flows in 2013 reflects an increase in the inflation rate used to determine the ARO settlement amount.

STOCKBASED_COMPENSATION_PLANS_1

STOCK-BASED COMPENSATION PLANS (Details) (USD $)	12 Months Ended
In Millions, except Share data, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013	Dec. 31, 2012
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	18,397		15,068
Fair Value Per Share (in dollars per share)	$48.20		$50.73
Expected volatility, measurement period	3 years
Vesting period of shares	3 years		3 years
Cost of Restricted Stock Awards	$0.20		$0.40	$0.40
Employee Service Share-based Compensation, Allocation of Recognized Period Costs, Capitalized, Percentage	50.00%		50.00%	50.00%
Amount capitalized to Utility Plant	0.2
Unrecognized compensation cost of awards granted under the plan	0.5
Weighted average period over which unrecognized compensation cost is to be recognized (in years)	1 year 8 months 12 days
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, beginning balance (in shares)	15,068
Granted (in shares)	10,394
Vested (in shares)	-7,065	[1]
Nonvested Shares Outstanding, ending balance (in shares)	18,397		15,068
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, beginning balance (in dollars per share)	$50.73
Weighted Average Grant Date Fair Value, Granted (in dollars per share)	$48.53
Weighted Average Grant Date Fair Value, Vested (in dollars per share)	$54.08	[1]
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$48.20		$50.73
Number of shares awarded during the period			12,901	7,098
Market value of shares awarded			0.6	0.4
Cash payments to SJI relating to stock awards	$0.40		$0.40	$0.30
Officers and Key Employees [Member]
Weighted Average Grant Date Fair Value
Shares to be awarded	0
Number of shares awarded during the period	0
Jan. 2013 - TSR [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	4,001
Fair Value Per Share (in dollars per share)	$44.38
Expected Volatility	21.10%
Risk-Free Interest Rate	0.40%
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, ending balance (in shares)	4,001
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$44.38
Jan. 2013 - EPS [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	4,001
Fair Value Per Share (in dollars per share)	$51.18
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, ending balance (in shares)	4,001
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$51.18
Jan. 2014 - TSR [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	5,197
Fair Value Per Share (in dollars per share)	$42.62
Expected Volatility	20.00%
Risk-Free Interest Rate	0.80%
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, ending balance (in shares)	5,197
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$42.62
Jan. 2014 - EPS [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Shares Outstanding (in shares)	5,197
Fair Value Per Share (in dollars per share)	$54.44
Restricted stock award activity, excluding accrued dividend equivalents [Roll Forward}
Nonvested Shares Outstanding, ending balance (in shares)	5,197
Weighted Average Grant Date Fair Value
Weighted Average Grant Date Fair Value, Nonvested Shares Outstanding, ending balance (in dollars per share)	$54.44
Minimum [Member]
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 [Member]
Deferred Compensation Arrangement with Individual, Share-based Payments [Line Items]
Percentage of actual amount of shares that ultimately vest of original share units granted			150.00%
[1]	Performance targets during the three-year vesting period were not attained for the January 2012 grant. As a result, no shares will be awarded in 2015.

RATES_AND_REGULATORY_ACTIONS_D

RATES AND REGULATORY ACTIONS (Details) (USD $)	0 Months Ended	1 Months Ended							24 Months Ended	1 Months Ended					12 Months Ended	276 Months Ended	1 Months Ended
	Oct. 01, 2014	Sep. 30, 2014	Aug. 31, 2014	Sep. 30, 2013	Jun. 30, 2013	Feb. 28, 2013	Jul. 31, 2012	Sep. 30, 2010	Dec. 31, 2013	Jan. 31, 2010	Oct. 31, 2006	Jan. 31, 2014	Jan. 31, 2013	Jan. 31, 2009	Dec. 31, 2014	Dec. 31, 2014	Nov. 30, 2012	Aug. 31, 2008	Oct. 31, 2013	31-May-14	31-May-13	Jun. 30, 2012	Oct. 31, 2012	Oct. 31, 2011	31-May-12	Jun. 30, 2011	Mar. 31, 2011	Sep. 30, 2012	Jul. 31, 2013	Jan. 31, 2015	Jul. 31, 2014	Jul. 31, 2011	Jun. 30, 2014
									customer						sites	sites
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase		$20,000,000						$42,100,000
Public Utilities, Rate of Return on Base Rate		7.10%						8.21%
Public Utilities, Return on Common Equity		9.75%						10.30%
Public Utilities, Annual Depreciation Reduction Attributable To Petition								1,200,000
Investment Requested to be Recovered through CIRT, Investments To Be Rolled to Base Rate									22,500,000										95,000,000
Public Utilities, Depreciate Rate	2.10%	2.10%							2.40%
Investment Requested to be Recovered through CIRT III, Term of AIRP						4 years	5 years
Investment Requested to be Recovered through CIRT III, Amount of AIRP						141,200,000	250,000,000
Investment Requested to be Recovered through CIRT III, Annual Amount of AIRP						35,300,000
Investment Requested to be Recovered through SHARP			103,500,000	280,000,000
Investment Requested to be Recovered through SHARP, Term			3 years	7 years
Number of sites for environmental cleanup															12	12
Regulatory Assets									296,081,000						357,160,000	357,160,000
Regulated Operations, Number of Customers Purchasing Energy Commodities From A Provider Other Then The Reporting Entity									38,347
Costs Requested for Deferral, Storm Related					700,000
Environmental Restoration Costs Expended Net [Member]
Schedule of Capitalization [Line Items]
Regulatory Assets									29,945,000						29,540,000	29,540,000
Other Regulatory Assets, Deferred Pipeline Integrity Costs [Member]
Schedule of Capitalization [Line Items]
Regulatory Assets									2,800,000						3,400,000	3,400,000
Conservation Incentive Program [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase								16,600,000
Amount of Regulatory Costs Approved																				21,800,000	17,800,000
Regulatory Costs, Period											3 years
Regulatory Costs, Extension Period										1 year
Amount of Regulatory Costs Not yet Approved, Prior Year Carryover																						28,000,000
Conservation Incentive Program [Member] | Non Weather [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																				4,200,000	2,300,000	8,400,000
Conservation Incentive Program [Member] | Weather [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																				26,000,000	15,500,000	19,600,000
Capital Investment Recovery Tracker [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase								6,800,000
Investment Requested to be Recovered through CIRT, Investments To Be Rolled to Base Rate																							110,600,000
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																							13,200,000
Investment Requested to be Recovered through CIRT, Revenue Increase				15,500,000
Capital Investment Recovery Tracker [Member] | Recovered in 2012 [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																								40,000,000
Capital Investment Recovery Tracker [Member] | Recovered in 2013 [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																								50,000,000
Capital Investment Recovery Tracker [Member] | Capital Expenditures [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																									35,000,000		60,300,000
Amount of Regulatory Costs Approved								81,300,000
Amount of Regulatory Costs Approved, Percent Change in Recoveries																										0.50%
Incremental Revenue [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase								18,700,000
Accelerated Infrastructure Replacement Program [Member]
Schedule of Capitalization [Line Items]
Public Utilities, Approved Base Rate Increase		7,500,000
Investment Requested to be Recovered through CIRT, Investments To Be Rolled to Base Rate		69,900,000
Basic Gas Supply Service [Member]
Schedule of Capitalization [Line Items]
Proceeds from Refunds From Favorable Regulatory Action												11,200,000	9,400,000
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																				27,000,000	600,000	27,000,000
Amount of Regulatory Costs Not yet Approved, Percent Change in Recoveries																				9.30%		-8.80%
Amount of Regulatory Costs Approved		27,000,000		600,000																								27,000,000
Amount of Regulatory Costs Approved, Percent Change in Recoveries																												-8.80%
Energy Efficiency Tracker [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)																				1,400,000	2,200,000	5,800,000			3,100,000	4,700,000
Amount of Regulatory Costs Approved		2,200,000			24,000,000																								2,100,000
Regulatory Costs, Period														2 years
Amount of Regulatory Costs Available Under Program														17,000,000
Energy Efficiency Tracker [Member] | Subsequent Event [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Approved, Statewide																														56,000,000
Societal Benefits Clause [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Not yet Approved, Increase/(Decrease)							11,800,000																						-6,400,000		-25,700,000	31,200,000
Remediation Adjustment Clause [Member]
Schedule of Capitalization [Line Items]
Number of sites for environmental cleanup															12	12
Amortization Period of Environmental Remediation Costs (in years)															7 years
Regulated Costs Recovered																106,100,000
Remediation Adjustment Clause [Member] | Environmental Restoration Costs Expended Net [Member]
Schedule of Capitalization [Line Items]
Regulatory Assets									29,900,000						29,500,000	29,500,000
New Jersey Clean Energy Program [Member]
Schedule of Capitalization [Line Items]
Regulatory Costs, Extension Period																	6 months
Amount of Regulatory Costs Approved, Statewide					345,000,000													1,200,000,000
Regulatory Costs For Which Reporting Entity is Responsible For																	7,500,000	41,500,000															14,500,000
Regulatory Costs For Which Reporting Entity is Responsible For, Period of Recovery (in years)																		4 years
Universal Service Fund [Member]
Schedule of Capitalization [Line Items]
Amount of Regulatory Costs Approved		7,900,000		5,800,000																								8,200,000
Amount of Regulatory Costs Approved, Statewide		71,800,000		54,400,000																								78,000,000
Amount of Regulatory Costs Not yet Approved, Statewide, Increase (Decrease)					-29,400,000																	-500,000											19,900,000
Amount of Regulatory Costs Not Yet Approved, Annual Revenue Impact, Increase (Decrease)					-3,700,000																	-100,000											2,600,000
Amount of Regulatory Costs Approved, Annual Revenue Impact, (Increase) Decrease		($2,600,000)		$3,400,000																								$100,000

REGULATORY_ASSETS_AND_LIABILIT2

REGULATORY ASSETS AND LIABILITIES (Details) (USD $)	12 Months Ended
	Dec. 31, 2006	Dec. 31, 2014	Dec. 31, 2013
Regulatory Assets [Line Items]
Total regulatory assets		$357,160,000	$296,081,000
Number regulatory assets associated with environmental costs related to the cleanup of 12 sites where SJG or their predecessors previously operated gas manufacturing plants (in regulatory assets)		2
Number of sites where SJG or their predecessors previously operated gas manufacturing plants (in sites)		12
Environmental Restoration Costs: Expended - Net [Member]
Regulatory Assets [Line Items]
Total regulatory assets		29,540,000	29,945,000
Environmental Restoration Costs: Liability for Future Expenditures [Member]
Regulatory Assets [Line Items]
Total regulatory assets		124,308,000	119,492,000
Deferred Asset Retirement Obligation Costs [Member]
Regulatory Assets [Line Items]
Total regulatory assets		31,584,000	31,142,000
Deferred Pension and Other Postretirement Benefit Costs [Member]
Regulatory Assets [Line Items]
Total regulatory assets		99,040,000	59,284,000
Regulatory asset increased	37,100,000
Deferred Gas Costs - Net [Member]
Regulatory Assets [Line Items]
Total regulatory assets		32,202,000	0
Conservation Incentive Program Receivable [Member]
Regulatory Assets [Line Items]
Total regulatory assets		0	10,526,000
Societal Benefit Costs Receivable [Member]
Regulatory Assets [Line Items]
Total regulatory assets		385,000	10,408,000
Premium for Early Retirement of Debt [Member]
Regulatory Assets [Line Items]
Total regulatory assets		0	955,000
Deferred Interest Rate Contracts (Note 11) [Member]
Regulatory Assets [Line Items]
Total regulatory assets		7,325,000	3,735,000
Energy Efficiency Tracker [Member]
Regulatory Assets [Line Items]
Total regulatory assets		11,247,000	10,420,000
Pipeline Supplier Service Charges [Member]
Regulatory Assets [Line Items]
Total regulatory assets		5,441,000	7,106,000
Pipeline Integrity Cost [Member]
Regulatory Assets [Line Items]
Total regulatory assets		3,431,000	2,902,000
AFUDC - Equity Related Deferrals [Member]
Regulatory Assets [Line Items]
Total regulatory assets		10,781,000	7,810,000
Other Regulatory Assets [Member]
Regulatory Assets [Line Items]
Total regulatory assets		1,876,000	2,356,000
Allowance for Funds Used Under Construction, Equity Related Deferrals, Settlement [Member]
Regulatory Assets [Line Items]
Total regulatory assets		$3,600,000
Regulatory Costs, Original Recovery Period of Expenditures (in years)		3 years

REGULATORY_ASSETS_AND_LIABILIT3

REGULATORY ASSETS AND LIABILITIES 2 (Details) (USD $)	1 Months Ended
	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
Regulatory Liabilities [Line Items]
Regulatory Liabilities		$41,899,000	$60,949,000
Excess Plant Removal Costs [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities		35,940,000	40,029,000
Annual amortization reflected in depreciation expense	1,100,000
Deferred Revenue - Net [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities		0	19,067,000
Conservation Incentive Program - Payable [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities		4,700,000	0
Other Regulatory Liabilities [Member]
Regulatory Liabilities [Line Items]
Regulatory Liabilities		$1,259,000	$1,853,000

RELATED_PARTY_TRANSACTIONS_Det

RELATED PARTY TRANSACTIONS (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Operating Revenues/Affiliates:
Operating Revenues	$2,042	$2,689	$1,735
Energy-Related Derivative Losses	1,700	-400	-15,400
Operations Expense/Affiliates:
Operating Expenses	16,344	19,779	18,916
SJRG [Member]
Operating Revenues/Affiliates:
Operating Revenues	959	1,390	884
Cost of Sales	15,265	14,959	9,083
Energy-Related Derivative Losses	-1,582	887	15,407
Marina [Member]
Operating Revenues/Affiliates:
Operating Revenues	1,083	1,297	841
SJI [Member]
Operations Expense/Affiliates:
Operating Expenses	14,110	11,990	10,870
SJIS [Member]
Operations Expense/Affiliates:
Operating Expenses	0	5,531	5,397
Millennium [Member]
Operations Expense/Affiliates:
Operating Expenses	2,668	2,686	3,149
Other [Member]
Operating Revenues/Affiliates:
Operating Revenues	0	2	10
Operations Expense/Affiliates:
Operating Expenses	($434)	($428)	($500)

INCOME_TAXES_AND_CREDITS_Detai

INCOME TAXES AND CREDITS (Details) (USD $)	3 Months Ended								12 Months Ended
	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Tax Expense (Benefit), Continuing Operations, Income Tax Reconciliation [Abstract]
Tax at Statutory Rate									$35,482,000	$33,974,000	$32,183,000
Increase (Decrease) Resulting from:
State Income Taxes									1,935,000	4,833,000	5,302,000
Amortization of Investment Tax Credits									-211,000	-258,000	-287,000
ESOP Dividend									-1,109,000	-1,058,000	-1,027,000
AFUDC									-1,481,000	-916,000	-1,048,000
Other - Net									279,000	-1,742,000	-1,412,000
Net Income Taxes	9,455,000	534,000	2,379,000	22,527,000	11,322,000	471,000	2,269,000	20,771,000	34,895,000	34,833,000	33,711,000
Current:
Federal									60,000	-53,000	-4,635,000
State									2,642,000	2,946,000	-7,000
Total Current									2,702,000	2,893,000	-4,642,000
Deferred:
Federal									32,069,000	27,707,000	30,477,000
State									335,000	4,491,000	8,163,000
Total Deferred									32,404,000	32,198,000	38,640,000
Investment Tax Credits									-211,000	-258,000	-287,000
Net Income Taxes	9,455,000	534,000	2,379,000	22,527,000	11,322,000	471,000	2,269,000	20,771,000	34,895,000	34,833,000	33,711,000
Annual amortization rate of investment tax credits									3.00%
Current:
Current Deferred Tax Asset - Net	-44,064,000				-23,309,000				-44,064,000	-23,309,000
Noncurrent:
Noncurrent Deferred Tax Liability – Net	435,022,000				380,975,000				435,022,000	380,975,000
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1,				547,000				503,000	547,000	503,000	421,000
Increase as a result of tax position taken in prior years									5,000	44,000	82,000
Decrease due to a lapse in the statue of limitations									0	0	0
Settlements									0	0	0
Balance at December 31,	552,000				547,000				552,000	547,000	503,000
Accrued interest and penalties on unrecognized tax benefits	700,000				600,000				700,000	600,000	600,000
Internal Revenue Service (IRS) [Member]
Noncurrent:
Operating loss carryforwards	152,700,000								152,700,000
Internal Revenue Service (IRS) [Member] | 2031 [Member]
Noncurrent:
Operating loss carryforwards	63,000,000								63,000,000
Internal Revenue Service (IRS) [Member] | 2032 [Member]
Noncurrent:
Operating loss carryforwards	4,200,000								4,200,000
Internal Revenue Service (IRS) [Member] | 2034 [Member]
Noncurrent:
Operating loss carryforwards	85,500,000								85,500,000
SJI [Member] | Prepaid Taxes [Member]
Noncurrent:
Income taxes due from parent company	0				0				0	0
Classified as Current [Member]
Current:
Net Operating Loss Carryforward	-40,573,000				-27,600,000				-40,573,000	-27,600,000
Budget Billing - Customer Accounts	1,138,000				1,152,000				1,138,000	1,152,000
Provision for Uncollectibles	-2,676,000				-1,726,000				-2,676,000	-1,726,000
Conservation Incentive Program	-2,027,000				4,631,000				-2,027,000	4,631,000
Section 461 Prepayments	1,026,000				1,156,000				1,026,000	1,156,000
Other	-952,000				-922,000				-952,000	-922,000
Classified as Noncurrent [Member]
Current:
Net Operating Loss Carryforward	-12,887,000				-8,764,000				-12,887,000	-8,764,000
Noncurrent:
Book Versus Tax Basis of Property	417,178,000				371,684,000				417,178,000	371,684,000
Deferred Fuel Costs - Net	22,959,000				1,330,000				22,959,000	1,330,000
Environmental Remediation	13,500,000				14,392,000				13,500,000	14,392,000
Deferred Regulatory Costs	6,333,000				13,665,000				6,333,000	13,665,000
Deferred State Tax	-17,390,000				-15,471,000				-17,390,000	-15,471,000
Investment Tax Credit Basis Gross-Up	-77,000				-185,000				-77,000	-185,000
Deferred Pension & Other Post Retirement Benefits	39,891,000				24,218,000				39,891,000	24,218,000
Pension & Other Post Retirement Benefits	-27,782,000				-14,152,000				-27,782,000	-14,152,000
Deferred Revenues	-11,452,000				-9,266,000				-11,452,000	-9,266,000
Other	$4,749,000				$3,524,000				$4,749,000	$3,524,000

LONGTERM_DEBT_Details

LONG-TERM DEBT (Details) (USD $)	1 Months Ended
	Sep. 30, 2014	Jul. 31, 2014	Dec. 31, 2014		Dec. 31, 2013		Jun. 30, 2014	Nov. 30, 2013	Jan. 31, 2014	Oct. 31, 2013
Debt Instrument [Line Items]
Total Long-Term Debt Outstanding			$543,000,000	[1]	$475,000,000	[1]
Less Current Maturities			-35,909,000	[1],[2]	-21,000,000	[1],[2]
Long-Term Debt			507,091,000	[1]	454,000,000	[1]
Long-term Debt, Fiscal Year Maturity [Abstract]
2015			35,909,000
2016			27,909,000
2017			74,909,000
2018			38,909,000
2019			18,909,000
Letter of credit provided			210,000,000
Medium-term Notes [Member]
Debt Instrument [Line Items]
Stated interest rate	5.12%	4.52%
Long-term Debt, Fiscal Year Maturity [Abstract]
Extinguishment of Debt, Amount	10,000,000	11,000,000
Term Line of Credit [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Letter of credit provided							200,000,000
First Mortgage Bonds [Member] | Series Due 2014, 4.52% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.52%
Total Long-Term Debt Outstanding			0	[1],[3],[4]	11,000,000	[1],[3],[4]
First Mortgage Bonds [Member] | Series Due 2014, 5.115% [Member]
Debt Instrument [Line Items]
Stated interest rate			5.12%
Total Long-Term Debt Outstanding			0	[1],[4],[5]	10,000,000	[1],[4],[5]
First Mortgage Bonds [Member] | Series Due 2015, 5.387% [Member]
Debt Instrument [Line Items]
Stated interest rate			5.39%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2016, 5.437% [Member]
Debt Instrument [Line Items]
Stated interest rate			5.44%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2016, 4.60% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.60%
Total Long-Term Debt Outstanding			17,000,000	[1],[4]	17,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2017, 4.657% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.66%
Total Long-Term Debt Outstanding			15,000,000	[1],[4]	15,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2018, 7.97% [Member]
Debt Instrument [Line Items]
Stated interest rate			7.97%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2018, 7.125% [Member]
Debt Instrument [Line Items]
Stated interest rate			7.13%
Total Long-Term Debt Outstanding			20,000,000	[1],[4]	20,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2019, 5.587% [Member]
Debt Instrument [Line Items]
Stated interest rate			5.59%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2024, 3.00% [Member]
Debt Instrument [Line Items]
Stated interest rate			3.00%
Total Long-Term Debt Outstanding			50,000,000	[1],[4]	50,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2024, 3.03% [Member]
Debt Instrument [Line Items]
Stated interest rate			3.03%
Total Long-Term Debt Outstanding			35,000,000	[1],[4]	35,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2025, 3.63% [Member]
Debt Instrument [Line Items]
Stated interest rate			3.63%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2026, 4.84% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.84%
Total Long-Term Debt Outstanding			15,000,000	[1],[4]	15,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2026, 4.93% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.93%
Total Long-Term Debt Outstanding			45,000,000	[1],[4]	45,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2027, 4.03% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.03%
Total Long-Term Debt Outstanding			45,000,000	[1],[4]	45,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2030, 4.01% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.01%					4.01%
Total Long-Term Debt Outstanding			50,000,000	[1],[4],[6]	50,000,000	[1],[4],[6]		50,000,000
First Mortgage Bonds [Member] | Series Due 2030, 4.23% [Member]
Debt Instrument [Line Items]
Stated interest rate			4.23%						4.23%
Total Long-Term Debt Outstanding			30,000,000	[1],[4],[7]	0	[1],[4],[7]
Long-term Debt, Fiscal Year Maturity [Abstract]
Debt Instrument, Face Amount									30,000,000
First Mortgage Bonds [Member] | Series Due 2032, 3.74% [Member]
Debt Instrument [Line Items]
Stated interest rate			3.74%
Total Long-Term Debt Outstanding			35,000,000	[1],[4]	35,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2033, 5.55% [Member]
Debt Instrument [Line Items]
Stated interest rate			5.55%
Total Long-Term Debt Outstanding			32,000,000	[1],[4]	32,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2034, 6.213% [Member]
Debt Instrument [Line Items]
Stated interest rate			6.21%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
First Mortgage Bonds [Member] | Series Due 2035, 5.45% [Member]
Debt Instrument [Line Items]
Stated interest rate			5.45%
Total Long-Term Debt Outstanding			10,000,000	[1],[4]	10,000,000	[1],[4]
Bonds at variable rates [Member] | Series A 2006 Tax-Exempt First Mortgage Bonds, Variable Rate, due 2036 [Member]
Debt Instrument [Line Items]
Total Long-Term Debt Outstanding			25,000,000	[1],[2]	25,000,000	[1],[2]
Long-term Debt, Fiscal Year Maturity [Abstract]
Interest rate at end of period			0.08%
Loans Payable [Member] | Term Line of Credit [Member]
Debt Instrument [Line Items]
Total Long-Term Debt Outstanding			59,000,000	[1],[8]	0	[1],[8]
Medium-term Notes [Member]
Long-term Debt, Fiscal Year Maturity [Abstract]
Approved borrowing capacity										$200,000,000
[1]	Long-term debt maturities and sinking funds requirements for the succeeding five years are as follows (in thousands): 2015, $35,909; 2016, $27,909; 2017, $74,909; 2018, $38,909; 2019, $18,909.
[2]	These variable rate demand bonds bear interest at a floating rate that resets weekly. The interest rate as of December 31, 2014 was 0.08%. Liquidity support on these bonds is provided under a separate letter of credit facility that expires in August, 2015; as such, these bonds have been included in the current portion of long-term debt. These bonds contain no financial covenants.
[3]	In July 2014, SJG retired $11.0 million aggregate principal amount of 4.52% Medium Term Notes (MTN's) at maturity.
[4]	Our First Mortgage dated October 1, 1947, as supplemented, securing the First Mortgage Bonds constitutes a direct first mortgage lien on substantially all utility plant.
[5]	In September 2014, SJG retired $10.0 million aggregate principal amount of 5.115% MTN's at maturity.
[6]	In November 2013, SJG issued $50.0 million aggregate principal amount of 4.01% MTN's due November 2030.
[7]	In January 2014, SJG issued $30.0 million aggregate principal amount of 4.23% MTN's due January 2030.
[8]	In June 2014, SJG entered into a $200.0 million multiple-draw term facility offered by a syndicate of banks which expires in June 2017. SJG can draw under this facility through June 2016 and this facility bears interest at a floating rate based on LIBOR plus a spread determined by SJG's credit ratings. As of December 31, 2014, SJG had borrowed an aggregate $59.0 million under this facility and the proceeds were used to pay down short-term debt.

FINANCIAL_INSTRUMENTS_Details

FINANCIAL INSTRUMENTS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Schedule of Financial Instruments [Line Items]
Restricted Investments	$7,961,000		$680,000
Term	5 years
Carrying amount of long-term debt	543,000,000	[1]	475,000,000	[1]
Unnamed Counterparty [Member]
Schedule of Financial Instruments [Line Items]
Restricted Investments	7,800,000		-300,000
Fair Value, Inputs, Level 1 [Member]
Schedule of Financial Instruments [Line Items]
Restricted investments held in escrow	100,000		100,000
Margin accounts with selected counterparties to support risk management activities	0		500,000
Fair Value, Inputs, Level 2 [Member]
Schedule of Financial Instruments [Line Items]
Estimated fair value of long-term debt	587,300,000		486,500,000
Carrying amount of long-term debt	543,000,000		475,000,000
Fair Value, Inputs, Level 2 [Member] | Financing Receivable [Member]
Schedule of Financial Instruments [Line Items]
Long-term receivables, net of unamortized discount	15,000,000		15,000,000
Imputed interest on long term receivables	$1,300,000		$1,300,000
[1]	Long-term debt maturities and sinking funds requirements for the succeeding five years are as follows (in thousands): 2015, $35,909; 2016, $27,909; 2017, $74,909; 2018, $38,909; 2019, $18,909.

LINES_OF_CREDIT_Details

LINES OF CREDIT (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Line of Credit Facility [Line Items]
Total Facility	$210,000,000
Usage	101,400,000
Available Liquidity	108,600,000
Average borrowings outstanding during the period	52,300,000	91,400,000
Maximum amounts outstanding during the period	105,000,000	121,900,000
Weighted average borrowing cost	0.45%	0.37%	0.48%
Minimum [Member]
Line of Credit Facility [Line Items]
Financial covenant, ratio of indebtedness to consolidated total capitalization minimum (more than)	0.65
Revolving Credit Facility [Member]
Line of Credit Facility [Line Items]
Total Facility	200,000,000
Usage	101,400,000
Available Liquidity	98,600,000
Expiration Date	May-18
Uncommitted Bank Lines [Member]
Line of Credit Facility [Line Items]
Total Facility	10,000,000
Usage	0
Available Liquidity	10,000,000
Expiration Date	Aug-15
South Jersey Gas Commercial Paper Program [Member]
Line of Credit Facility [Line Items]
Total Facility	$200,000,000
Fixed maturities of notes, at maximum number of days (in days)	270 days

RETAINED_EARNINGS_Details

RETAINED EARNINGS (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Equity [Abstract]
Equity infusions from SJI	$25,000	$25,000	$0

PENSION_AND_OTHER_POSTRETIREME2

PENSION AND OTHER POSTRETIREMENT BENEFITS (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Benefits [Member]
Net periodic benefit cost [Abstract]
Service Cost	$3,697	$4,487	$3,718
Interest Cost	8,952	7,886	8,008
Expected Return on Plan Assets	-10,818	-9,435	-8,249
Amortization:
Prior Service Cost (Credits)	177	208	207
Actuarial Loss	4,864	7,608	6,432
Net Periodic Benefit Cost	6,872	10,754	10,116
Capitalized Benefit Costs	-3,047	-5,002	-4,684
Affiliate SERP Allocations	-1,313	-1,389	-1,107
Total Net Periodic Benefit Expense	2,512	4,363	4,325
Other Postretirement Benefits [Member]
Net periodic benefit cost [Abstract]
Service Cost	585	771	704
Interest Cost	2,297	2,221	2,443
Expected Return on Plan Assets	-2,467	-2,158	-1,910
Amortization:
Prior Service Cost (Credits)	133	-195	-195
Actuarial Loss	770	1,555	1,534
Net Periodic Benefit Cost	1,318	2,194	2,576
Capitalized Benefit Costs	-722	-1,172	-1,340
Affiliate SERP Allocations	0	0	0
Total Net Periodic Benefit Expense	$596	$1,022	$1,236

PENSION_AND_OTHER_POSTRETIREME3

PENSION AND OTHER POSTRETIREMENT BENEFITS 2 (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Pension Benefits [Member]
Regulatory Assets
Beginning Balance	$42,632	$68,713
Amounts Arising During the Period, Net Actuarial Gain (Loss)	31,075	-20,554
Amounts Arising During the Period, Prior Service Cost (Credit)	486
Amounts Amortized to Net Periodic Costs, Net Actuarial Loss	-2,841	-5,319
Amounts Amortized to Net Periodic Costs, Prior Service (Cost) Credit	-175	-208
Ending Balance	71,177	42,632
Accumulated Other Comprehensive Loss (pre-tax)
Beginning Balance	18,043	21,908
Amounts Arising During the Period, Net Actuarial Gain (Loss)	7,102	-1,576
Amounts Arising During the Period, Prior Service Cost (Credit)	0
Amounts Amortized to Net Periodic Costs, Net Actuarial Loss	-1,975	-2,289
Amounts Amortized to Net Periodic Costs, Prior Service (Cost) Credit	0	0
Ending Balance	23,170	18,043
Other Postretirement Benefits [Member]
Regulatory Assets
Beginning Balance	16,652	27,184
Amounts Arising During the Period, Net Actuarial Gain (Loss)	7,826	-9,171
Amounts Arising During the Period, Prior Service Cost (Credit)	4,146
Amounts Amortized to Net Periodic Costs, Net Actuarial Loss	-628	-1,555
Amounts Amortized to Net Periodic Costs, Prior Service (Cost) Credit	-133	194
Ending Balance	27,863	16,652
Accumulated Other Comprehensive Loss (pre-tax)
Beginning Balance	0	0
Amounts Arising During the Period, Net Actuarial Gain (Loss)	0	0
Amounts Amortized to Net Periodic Costs, Net Actuarial Loss	0	0
Amounts Amortized to Net Periodic Costs, Prior Service (Cost) Credit	0	0
Ending Balance	$0	$0

PENSION_AND_OTHER_POSTRETIREME4

PENSION AND OTHER POSTRETIREMENT BENEFITS 3 (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior Service Costs	$199
Net Actuarial Loss	5,922
Net Actuarial Loss	2,750
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Prior Service Costs	499
Net Actuarial Loss	1,235
Net Actuarial Loss	$0

PENSION_AND_OTHER_POSTRETIREME5

PENSION AND OTHER POSTRETIREMENT BENEFITS 4 (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Amounts Recognized in the Statement of Financial Position Consist of:
Current Liabilities	($1,515,000)	($1,241,000)
Noncurrent Liabilities	-95,241,000	-48,197,000
Pension Benefits [Member]
Change in Benefit Obligations:
Benefit Obligation at Beginning of Year	180,668,000	186,899,000
Service Cost	3,697,000	4,487,000	3,718,000
Interest Cost	8,952,000	7,886,000	8,008,000
Actuarial (Gain) Loss	35,634,000	-11,514,000
Retiree Contributions	0	0
Plan Amendments	534,000	0
Benefits Paid	-7,880,000	-7,090,000
Benefit Obligation at End of Year	221,605,000	180,668,000	186,899,000
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Year	142,674,000	119,391,000
Actual Return on Plan Assets	8,275,000	20,049,000
Employer Contributions	1,499,000	10,324,000
Retiree Contributions	0	0
Benefits Paid	-7,880,000	-7,090,000
Fair Value of Plan Assets at End of Year	144,568,000	142,674,000	119,391,000
Amounts Recognized in the Statement of Financial Position Consist of:
Current Liabilities	-1,515,000	-1,241,000
Noncurrent Liabilities	-75,522,000	-36,753,000
Net Amount Recognized at End of Year	-77,037,000	-37,994,000
Amounts Recognized in Regulatory Assets Consist of:
Prior Service Costs	944,000	634,000
Net Actuarial Loss	70,233,000	41,998,000
Net Amount Recognized at End of Year	71,177,000	42,632,000	68,713,000
Amounts Recognized in Accumulated Other Comprehensive Loss Consist of:
Net Actuarial Loss	23,170,000	18,043,000
Projected benefit obligation	176,300,000	143,500,000
Accumulated benefit obligation	161,300,000	131,400,000
Other Postretirement Benefits [Member]
Change in Benefit Obligations:
Benefit Obligation at Beginning of Year	50,915,000	55,615,000
Service Cost	585,000	771,000	704,000
Interest Cost	2,297,000	2,221,000	2,443,000
Actuarial (Gain) Loss	6,008,000	-4,552,000
Retiree Contributions	452,000	335,000
Plan Amendments	4,146,000	0
Benefits Paid	-3,733,000	-3,475,000
Benefit Obligation at End of Year	60,670,000	50,915,000	55,615,000
Change in Plan Assets:
Fair Value of Plan Assets at Beginning of Year	39,471,000	32,694,000
Actual Return on Plan Assets	507,000	5,101,000
Employer Contributions	4,254,000	4,816,000
Retiree Contributions	452,000	335,000
Benefits Paid	-3,733,000	-3,475,000
Fair Value of Plan Assets at End of Year	40,951,000	39,471,000	32,694,000
Amounts Recognized in the Statement of Financial Position Consist of:
Current Liabilities	0	0
Noncurrent Liabilities	-19,719,000	-11,444,000
Net Amount Recognized at End of Year	-19,719,000	-11,444,000
Amounts Recognized in Regulatory Assets Consist of:
Prior Service Costs	4,965,000	952,000
Net Actuarial Loss	22,898,000	15,700,000
Net Amount Recognized at End of Year	27,863,000	16,652,000	27,184,000
Amounts Recognized in Accumulated Other Comprehensive Loss Consist of:
Net Actuarial Loss	0	0
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Amounts Recognized in Accumulated Other Comprehensive Loss Consist of:
Projected benefit obligation	45,300,000	37,200,000
Accumulated benefit obligation	44,000,000	36,200,000
SJI [Member] | Pension Benefits [Member]
Funded Status at End of Year:
Accrued Net Benefit Cost at End of Year	-77,037,000	-37,994,000
SJI [Member] | Other Postretirement Benefits [Member]
Funded Status at End of Year:
Accrued Net Benefit Cost at End of Year	($19,719,000)	($11,444,000)

PENSION_AND_OTHER_POSTRETIREME6

PENSION AND OTHER POSTRETIREMENT BENEFITS 5 (Details)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Pension Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount Rate	4.25%	5.09%
Rate of Compensation Increase	3.50%	3.50%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount Rate	5.09%	4.26%	5.03%
Expected Long-Term Return on Plan Assets	7.75%	7.50%	7.50%
Rate of Compensation Increase	3.50%	3.25%	3.25%
Other Postretirement Benefits [Member]
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Benefit Obligation [Abstract]
Discount Rate	4.20%	4.91%
Rate of Compensation Increase	3.50%	3.50%
Defined Benefit Plan, Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost [Abstract]
Discount Rate	4.91%	4.14%	4.92%
Expected Long-Term Return on Plan Assets	6.25%	6.60%	6.60%
Rate of Compensation Increase	3.50%	3.25%	3.25%

PENSION_AND_OTHER_POSTRETIREME7

PENSION AND OTHER POSTRETIREMENT BENEFITS 6 (Details) (Other Postretirement Benefits [Member])	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Other Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Medical Care and Drug Cost Trend Rate Assumed for Next Year	7.00%	7.00%
Dental Care Cost Trend Rate Assumed for Next Year	4.75%	4.75%
Rate to which Cost Trend Rates are Assumed to Decline (the Ultimate Trend Rate)	4.75%	4.75%
Year that the Rate Reaches the Ultimate Trend Rate	2023	2023

PENSION_AND_OTHER_POSTRETIREME8

PENSION AND OTHER POSTRETIREMENT BENEFITS 7 (Details) (Other Postretirement Benefits [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014
Other Postretirement Benefits [Member]
Defined Benefit Plan, Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]
1 - Percentage Point Increase, Effect on the Total of Service and Interest Cost	$112
1 - Percentage Point Increase, Effect on Postretirement Benefit Obligation	3,806
1 - Percentage Point Decrease, Effect on the Total of Service and Interest Cost	-94
1 - Percentage Point Decrease, Effect on Postretirement Benefit Obligation	($3,065)

PENSION_AND_OTHER_POSTRETIREME9

PENSION AND OTHER POSTRETIREMENT BENEFITS 8 (Details) (Pension Benefits [Member], USD $)	12 Months Ended
	Dec. 31, 2014
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Required Capitalization for Plan Asset Allocation (less than)	250,000,000
Defined Benefit Plan, Required Capitalization for Plan Asset Allocation, Small Cap	50,000,000
Equity Securities, U.S. Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Minimum	28.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Maximum	48.00%
Equity Securities, International Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Minimum	13.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Maximum	25.00%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Minimum	32.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Maximum	42.00%
Other Investments [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Minimum	2.00%
Defined Benefit Plan, Target Allocation Percentage of Assets, Equity Securities, Range Maximum	14.00%

Recovered_Sheet1

PENSION AND OTHER POSTRETIREMENT BENEFITS 9 (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Pension Benefits [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year	$142,674				$119,391
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	144,568				119,391
Fund Valuations Lag Period	90 days
Pension Benefits [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	554	[1]	334	[1]
Pension Benefits [Member] | STIF-Type Instrument [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	1,003	[2]	943	[2]
Pension Benefits [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	41,000	[1]	41,527	[1]
Pension Benefits [Member] | U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	10,380	[3]	9,342	[3]
Pension Benefits [Member] | U.S. Mid-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	4,122	[3]	3,313	[3]
Pension Benefits [Member] | U.S. Small-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	186	[3]
Pension Benefits [Member] | Equity Securities, International Securities [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	2,698	[3]	2,935	[3]
Pension Benefits [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	24,796	[1]	27,312	[1]
Pension Benefits [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	38,740	[1]	36,728	[1]
Pension Benefits [Member] | Guaranteed Insurance Contract [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	8,738	[4]	9,071	[4]
Pension Benefits [Member] | Hedge Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	3,469	[5]	3,328	[5]
Pension Benefits [Member] | Private Equity Fund [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	2,895	[6]	2,440	[6]
Pension Benefits [Member] | Common/Collective Trust Fund – Real Estate [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	5,987	[7]	5,401	[7]
Pension Benefits [Member] | Level 1 [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	17,386		15,590
Pension Benefits [Member] | Level 1 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 1 [Member] | STIF-Type Instrument [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[2]	0	[2]
Pension Benefits [Member] | Level 1 [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 1 [Member] | U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	10,380	[3]	9,342	[3]
Pension Benefits [Member] | Level 1 [Member] | U.S. Mid-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	4,122	[3]	3,313	[3]
Pension Benefits [Member] | Level 1 [Member] | U.S. Small-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	186	[3]
Pension Benefits [Member] | Level 1 [Member] | Equity Securities, International Securities [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	2,698	[3]	2,935	[3]
Pension Benefits [Member] | Level 1 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 1 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 1 [Member] | Guaranteed Insurance Contract [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[4]	0	[4]
Pension Benefits [Member] | Level 1 [Member] | Hedge Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[5]	0	[5]
Pension Benefits [Member] | Level 1 [Member] | Private Equity Fund [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[6]	0	[6]
Pension Benefits [Member] | Level 1 [Member] | Common/Collective Trust Fund – Real Estate [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[7]	0	[7]
Pension Benefits [Member] | Level 2 [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	106,093		106,844
Pension Benefits [Member] | Level 2 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	554	[1]	334	[1]
Pension Benefits [Member] | Level 2 [Member] | STIF-Type Instrument [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	1,003	[2]	943	[2]
Pension Benefits [Member] | Level 2 [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	41,000	[1]	41,527	[1]
Pension Benefits [Member] | Level 2 [Member] | U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]	0	[3]
Pension Benefits [Member] | Level 2 [Member] | U.S. Mid-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]	0	[3]
Pension Benefits [Member] | Level 2 [Member] | U.S. Small-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]
Pension Benefits [Member] | Level 2 [Member] | Equity Securities, International Securities [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]	0	[3]
Pension Benefits [Member] | Level 2 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	24,796	[1]	27,312	[1]
Pension Benefits [Member] | Level 2 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	38,740	[1]	36,728	[1]
Pension Benefits [Member] | Level 2 [Member] | Guaranteed Insurance Contract [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[4]	0	[4]
Pension Benefits [Member] | Level 2 [Member] | Hedge Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[5]	0	[5]
Pension Benefits [Member] | Level 2 [Member] | Private Equity Fund [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[6]	0	[6]
Pension Benefits [Member] | Level 2 [Member] | Common/Collective Trust Fund – Real Estate [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[7]	0	[7]
Pension Benefits [Member] | Level 3 [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year	20,240		17,233
Actual return on plan assets:
Relating to assets still held at the reporting date	1,103		759
Relating to assets sold during the period	270		359
Purchases, Sales and Settlements	-524		1,889
Fair Value of Plan Assets at End of Year	21,089		20,240
Pension Benefits [Member] | Level 3 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 3 [Member] | STIF-Type Instrument [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[2]	0	[2]
Pension Benefits [Member] | Level 3 [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 3 [Member] | U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]	0	[3]
Pension Benefits [Member] | Level 3 [Member] | U.S. Mid-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]	0	[3]
Pension Benefits [Member] | Level 3 [Member] | Equity Securities, International Securities [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[3]	0	[3]
Pension Benefits [Member] | Level 3 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 3 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Pension Benefits [Member] | Level 3 [Member] | Guaranteed Insurance Contract [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year	9,071	[4]	9,898
Actual return on plan assets:
Relating to assets still held at the reporting date	396		-68
Relating to assets sold during the period	10		14
Purchases, Sales and Settlements	-739		-773
Fair Value of Plan Assets at End of Year	8,738	[4]	9,071	[4]
Pension Benefits [Member] | Level 3 [Member] | Hedge Funds [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year	3,328	[5]	0
Actual return on plan assets:
Relating to assets still held at the reporting date	141		124
Relating to assets sold during the period	0		0
Purchases, Sales and Settlements	0		3,204
Fair Value of Plan Assets at End of Year	3,469	[5]	3,328	[5]
Pension Benefits [Member] | Level 3 [Member] | Private Equity Fund [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year	2,440	[6]	2,557
Actual return on plan assets:
Relating to assets still held at the reporting date	-20		80
Relating to assets sold during the period	260		345
Purchases, Sales and Settlements	215		-542
Fair Value of Plan Assets at End of Year	2,895	[6]	2,440	[6]
Pension Benefits [Member] | Level 3 [Member] | Common/Collective Trust Fund – Real Estate [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year	5,401	[7]	4,778
Actual return on plan assets:
Relating to assets still held at the reporting date	586		623
Relating to assets sold during the period	0		0
Purchases, Sales and Settlements	0		0
Fair Value of Plan Assets at End of Year	5,987	[7]	5,401	[7]
Other Postretirement Benefits [Member]
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward]
Fair Value of Plan Assets at Beginning of Year					32,694
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	40,951		39,471		32,694
Other Postretirement Benefits [Member] | Cash and Cash Equivalents [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	142
Other Postretirement Benefits [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	10,006	[1]	12,412	[1]
Other Postretirement Benefits [Member] | Mutual Fund - U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	4,447	[8]	2,814	[8]
Other Postretirement Benefits [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	7,030	[1]	10,031	[1]
Other Postretirement Benefits [Member] | Equity Securities, Mutual Fund, International [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	1,671	[8]
Other Postretirement Benefits [Member] | Common/Collective Trust [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	11,059	[1]	14,214	[1]
Other Postretirement Benefits [Member] | Mutual Funds - Bonds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	2,624	[8]
Other Postretirement Benefits [Member] | Mutual Funds - REITs [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	286	[8]
Other Postretirement Benefits [Member] | Company Owned Life Insurance [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	3,686	[9]
Other Postretirement Benefits [Member] | Level 1 [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	9,170		2,814
Other Postretirement Benefits [Member] | Level 1 [Member] | Cash and Cash Equivalents [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	142
Other Postretirement Benefits [Member] | Level 1 [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Other Postretirement Benefits [Member] | Level 1 [Member] | Mutual Fund - U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	4,447	[8]	2,814	[8]
Other Postretirement Benefits [Member] | Level 1 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Other Postretirement Benefits [Member] | Level 1 [Member] | Equity Securities, Mutual Fund, International [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	1,671	[8]
Other Postretirement Benefits [Member] | Level 1 [Member] | Common/Collective Trust [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Other Postretirement Benefits [Member] | Level 1 [Member] | Mutual Funds - Bonds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	2,624	[8]
Other Postretirement Benefits [Member] | Level 1 [Member] | Mutual Funds - REITs [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	286	[8]
Other Postretirement Benefits [Member] | Level 1 [Member] | Company Owned Life Insurance [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[9]
Other Postretirement Benefits [Member] | Level 2 [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	31,781		36,657
Other Postretirement Benefits [Member] | Level 2 [Member] | Cash and Cash Equivalents [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0
Other Postretirement Benefits [Member] | Level 2 [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	10,006	[1]	12,412	[1]
Other Postretirement Benefits [Member] | Level 2 [Member] | Mutual Fund - U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]	0	[8]
Other Postretirement Benefits [Member] | Level 2 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	7,030	[1]	10,031	[1]
Other Postretirement Benefits [Member] | Level 2 [Member] | Equity Securities, Mutual Fund, International [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]
Other Postretirement Benefits [Member] | Level 2 [Member] | Common/Collective Trust [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	11,059	[1]	14,214	[1]
Other Postretirement Benefits [Member] | Level 2 [Member] | Mutual Funds - Bonds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]
Other Postretirement Benefits [Member] | Level 2 [Member] | Mutual Funds - REITs [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]
Other Postretirement Benefits [Member] | Level 2 [Member] | Company Owned Life Insurance [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	3,686	[9]
Other Postretirement Benefits [Member] | Level 3 [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0		0
Other Postretirement Benefits [Member] | Level 3 [Member] | Cash and Cash Equivalents [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0
Other Postretirement Benefits [Member] | Level 3 [Member] | Common/Collective Trust Funds – U.S. [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Other Postretirement Benefits [Member] | Level 3 [Member] | Mutual Fund - U.S. Large-Cap [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]	0	[8]
Other Postretirement Benefits [Member] | Level 3 [Member] | Common/Collective Trust Funds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Other Postretirement Benefits [Member] | Level 3 [Member] | Equity Securities, Mutual Fund, International [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]
Other Postretirement Benefits [Member] | Level 3 [Member] | Common/Collective Trust [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[1]	0	[1]
Other Postretirement Benefits [Member] | Level 3 [Member] | Mutual Funds - Bonds [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]
Other Postretirement Benefits [Member] | Level 3 [Member] | Mutual Funds - REITs [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	0	[8]
Other Postretirement Benefits [Member] | Level 3 [Member] | Company Owned Life Insurance [Member]
Actual return on plan assets:
Fair Value of Plan Assets at End of Year	$0	[9]
Minimum [Member] | Other Postretirement Benefits [Member] | Equity Securities, U.S. Securities [Member]
Actual return on plan assets:
Target plan allocations	33.00%
Minimum [Member] | Other Postretirement Benefits [Member] | Equity Securities, International Securities [Member]
Actual return on plan assets:
Target plan allocations	20.00%
Minimum [Member] | Other Postretirement Benefits [Member] | Fixed Income Funds [Member]
Actual return on plan assets:
Target plan allocations	32.00%
Maximum [Member] | Other Postretirement Benefits [Member] | Equity Securities, U.S. Securities [Member]
Actual return on plan assets:
Target plan allocations	43.00%
Maximum [Member] | Other Postretirement Benefits [Member] | Equity Securities, International Securities [Member]
Actual return on plan assets:
Target plan allocations	30.00%
Maximum [Member] | Other Postretirement Benefits [Member] | Fixed Income Funds [Member]
Actual return on plan assets:
Target plan allocations	42.00%
[1]	This category represents common/collective trust fund investments through a commingled employee benefit trust (excluding real estate). These commingled funds are not traded publicly; however, the majority of the underlying assets held in these funds are stocks and bonds that are traded on active markets and prices for these assets are readily observable. Also included in these funds are interest rate swaps, asset backed securities, mortgage backed securities and other investments with observable market values. Holdings in these commingled funds are classified as Level 2 investments.
[2]	This category represents short-term investment funds held for the purpose of funding disbursement payment arrangements. Underlying assets are valued based on quoted prices in active markets, or where quoted prices are not available, based on models using observable market information. Since not all values can be obtained from quoted prices in active markets, these funds are classified as Level 2 investments.
[3]	This category of equity investments represents a managed portfolio of common stock investments in five sectors: telecommunications, electric utilities, gas utilities, water and energy. These common stocks are actively traded on exchanges and price quotes for these shares are readily available. These common stocks are classified as Level 1 investments.
[4]	This category represents SJI’s Group Annuity contracts with a nationally recognized life insurance company. The contracts are the assets of the plan, while the underlying assets of the contracts are owned by the contract holder. Valuation is based on a formula and calculation specified within the contract. Since the valuation is based on the reporting entity’s own assumptions, these contracts are classified as Level 3 investments.
[5]	This category represents a collection of underlying funds which are all domiciled outside of the United States. All of the underlying fund managers are based in the U.S.; however, they do not necessarily trade only in the U.S. markets. The fair value of these funds is determined by the underlying fund's general partner or manager. These funds are classified as Level 3 investments.
[6]	This category represents a limited partnership which includes several investments in U.S. leveraged buyout, venture capital, and special situation funds. Fund valuations are reported on a 90 day lag and, therefore, the value reported herein represents the market value as of September 30, 2014 and 2013, respectively. The fund’s investments are stated at fair value, which is generally based on the valuations provided by the general partners or managers of such investments. Fund investments are illiquid and resale is restricted. These funds are classified as Level 3 investments.
[7]	This category represents real estate common/collective trust fund investments through a commingled employee benefit trust. These commingled funds are part of a direct investment in a pool of real estate properties. These funds are valued by investment managers on a periodic basis using pricing models that use independent appraisals from sources with professional qualifications. Since these valuation inputs are not highly observable, the real estate funds are classified as Level 2 investments.
[8]	This category represents mutual fund investments. The mutual funds are actively traded on exchanges and price quotes for the shares are readily available. These mutual funds are classified as Level 1 investments.
[9]	This category represents Company-owned life insurance policies with a nationally known life insurance company. The value of these policies is backed by a series of common/collective trust funds held by the insurance carrier similar to category (a) above. Holdings in these insurance policies are classified as Level 2 investments.

Recovered_Sheet2

PENSION AND OTHER POSTRETIREMENT BENEFITS 10 (Details) (USD $)	12 Months Ended			1 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Jan. 31, 2015
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Pension Contributions	$0	$9,100,000	$19,757,000
Pension Benefits [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2015	8,444,000
2016	8,886,000
2017	9,143,000
2018	10,263,000
2019	11,174,000
2020- 2024	65,205,000
Pension Contributions	0	9,100,000
Pension Benefits [Member] | Subsequent Event [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Pension Contributions				12,000,000
Other Postretirement Benefits [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
2015	3,999,000
2016	4,199,000
2017	4,222,000
2018	4,285,000
2019	4,389,000
2020- 2024	23,421,000
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	3,600,000
Supplemental Employee Retirement Plans, Defined Benefit [Member]
Defined Benefit Plan, Expected Future Benefit Payments, Fiscal Year Maturity [Abstract]
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year	$1,500,000

Recovered_Sheet3

PENSION AND OTHER POSTRETIREMENT BENEFITS 11 (Details) (USD $)	12 Months Ended
In Millions, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Cost Recognized	$1.20	$1	$0.90
Employee Qualifying For Defined Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent	6.00%
Employee Not Qualifying For Defined Benefit Plan [Member]
Defined Benefit Plan Disclosure [Line Items]
Defined Contribution Plan, Maximum Annual Contribution Per Employee, Percent	50.00%
Defined Contribution Plan, Employer Matching Contribution, Percent	8.00%
Year End Contribution for Employees With Less Then Ten Years of Service	1,500,000
Years of Service Threshold to Determine Year End Contribution	10 years
Year End Contribution for Employees With More Then Ten Years of Service	2,000,000

COMMITMENTS_AND_CONTINGENCIES_1

COMMITMENTS AND CONTINGENCIES (Details) (USD $)	12 Months Ended		420 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2012
	unions		unions	sites
	sites		sites
Loss Contingencies [Line Items]
Letter of credit provided	$210,000,000		$210,000,000
Monthly gas supply related demand charges and reservation fees	3,900,000
Estimated litigation liability	500,000	500,000	500,000
Percentage of personnel represented in collective bargaining agreements	59.00%		59.00%
Number of unions	2		2
Number of sites for environmental cleanup	12		12
Number of sites covered by insurance				11
Insurance policy limit				50,000,000
Accrual for Environmental Loss Contingencies [Roll Forward]
Beginning of Year	119,492,000	107,410,000
Accruals	16,453,000	22,264,000	343,900,000
Expenditures	-11,637,000	-10,182,000	-219,600,000
End of Year	124,308,000	119,492,000	124,308,000
Standby Letter of Credit [Member]
Loss Contingencies [Line Items]
Letter of credit provided	25,200,000		25,200,000
Environmental Restoration Costs [Member]
Accrual for Environmental Loss Contingencies [Roll Forward]
Range of possible loss, minimum	124,300,000		124,300,000
Range of possible loss, maximum	223,300,000		223,300,000
Environmental Restoration Costs [Member] | Sites Comprising the Majority the Environmental Remediation [Member]
Accrual for Environmental Loss Contingencies [Roll Forward]
Range of possible loss, minimum	110,200,000		110,200,000
Range of possible loss, maximum	$198,400,000		$198,400,000
Number of sites affected by environmental remediation	6		6

FAIR_VALUE_OF_FINANCIAL_ASSETS2

FAIR VALUE OF FINANCIAL ASSETS AND FINANCIAL LIABILITIES (Details) (Fair Value, Measurements, Recurring [Member], USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Assets
Available-for-Sale Securities	$8,894	[1]	$8,696	[1]
Derivatives - Energy Related Assets	2,051	[2]	1,500	[2]
Total Assets	10,945		10,196
Liabilities
Derivatives - Energy Related Liabilities	7,603	[2]	759	[2]
Derivatives - Other	7,325	[3]	3,735	[3]
Total Liabilities	14,928		4,494
Level 1 [Member]
Assets
Available-for-Sale Securities	5,924	[1]	8,696	[1]
Derivatives - Energy Related Assets	2	[2]	1,409	[2]
Total Assets	5,926		10,105
Liabilities
Derivatives - Energy Related Liabilities	7,254	[2]	155	[2]
Derivatives - Other	0	[3]	0	[3]
Total Liabilities	7,254		155
Level 2 [Member]
Assets
Available-for-Sale Securities	2,970	[1]	0	[1]
Derivatives - Energy Related Assets	2,049	[2]	91	[2]
Total Assets	5,019		91
Liabilities
Derivatives - Energy Related Liabilities	349	[2]	604	[2]
Derivatives - Other	7,325	[3]	3,735	[3]
Total Liabilities	7,674		4,339
Level 3 [Member]
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 – 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 – 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
	Sep. 30, 2005	Dec. 31, 2014	Dec. 31, 2013
Derivative [Line Items]
Unrealized gain (losses) included in its BGSS related to open financial contracts		($5,600,000)	$700,000
Initial cost of Treasury Locks	1,400,000
Amortization period of Treasury Locks	30 years
Unamortized balance of Treasury Locks		1,000,000	1,000,000
South Jersey Gas Company [Member] | Interest Rate Swap, $12,500,000 Contract 1 [Member]
Derivative [Line Items]
Derivative, Notional Amount		12,500,000,000
Derivative, Fixed Interest Rate		3.43%
South Jersey Gas Company [Member] | Interest Rate Swap, $12,500,000 Contract 2 [Member]
Derivative [Line Items]
Derivative, Notional Amount		$12,500,000,000
Derivative, Fixed Interest Rate		3.43%
Basis and Index Related Purchase and Sales Contracts [Member]
Derivative [Line Items]
Outstanding derivative contracts notional amount		3.7
Natural Gas (in MMdts) [Member] | Derivative Transaction Type, Purchase [Member]
Derivative [Line Items]
Outstanding derivative contracts notional amount		8.9
Natural Gas (in MMdts) [Member] | Derivative Transaction Type, Sale [Member]
Derivative [Line Items]
Outstanding derivative contracts notional amount		0.6

DERIVATIVE_INSTRUMENTS_2_Detai

DERIVATIVE INSTRUMENTS 2 (Details) (Not Designated as Hedging Instrument [Member], USD $)	Dec. 31, 2014	Dec. 31, 2013
In Thousands, unless otherwise specified
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	$2,051	$1,500
Fair value Derivative Liabilities	14,928	4,494
Commodity Contract [Member] | Derivatives-Energy Related-Current [Member]
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	2,051	1,222
Fair value Derivative Liabilities	6,305	711
Commodity Contract [Member] | Derivatives-Energy Related-NonCurrent [Member]
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	0	278
Fair value Derivative Liabilities	1,298	48
Interest Rate Contract [Member] | Derivatives-Other [Member]
Derivatives, Fair Value [Line Items]
Fair value Derivative Assets	0	0
Fair value Derivative Liabilities	$7,325	$3,735

DERIVATIVE_INSTRUMENTS_3_Detai

DERIVATIVE INSTRUMENTS 3 (Details) (USD $)	Dec. 31, 2014		Dec. 31, 2013
In Thousands, unless otherwise specified
Derivatives - Energy Related [Member]
Offsetting Derivative Assets [Abstract]
Gross amounts of recognized assets/liabilities	$2,051		$1,500
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	2,051		1,500
Gross amounts not offset in the balance sheet, Financial Instruments	-2	[1]	-155	[1]
Gross amounts not offset in the balance sheet, Cash Collateral Posted	0		-498
Net amount	2,049		847
Offsetting Derivative Liabilities [Abstract]
Gross amounts of recognized assets/liabilities	-7,603		-759
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	-7,603		-759
Gross amounts not offset in the balance sheet, Financial Instruments	2	[2]	155	[2]
Gross amounts not offset in the balance sheet, Cash Collateral Posted	7,253		0
Net amount	-348		-604
Derivatives - Other [Member]
Offsetting Derivative Liabilities [Abstract]
Gross amounts of recognized assets/liabilities	-7,325		-3,735
Gross amount offset in the balance sheet	0		0
Net amounts of assets/liabilities in balance sheet	-7,325		-3,735
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	($7,325)		($3,735)
[1]	The balances at December 31, 2014 and December 31, 2013 were related to derivative liabilities which can be net settled against derivative assets.
[2]	The balances at December 31, 2014 and December 31, 2013 were related to derivative assets which can be net settled against derivative liabilities.

DERIVATIVE_INSTRUMENTS_4_Detai

DERIVATIVE INSTRUMENTS 4 (Details) (USD $)	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Losses reclassified from accumulated OCI into income	($46,000)	[1]	($46,000)	[1]	($46,000)	[1]
Realized gains losses, derivative instruments on energy-related contracts	$1,700,000		($400,000)		($15,400,000)
[1]	Included in Interest Charges

ACCUMULATED_OTHER_COMPREHENSIV2

ACCUMULATED OTHER COMPREHENSIVE LOSS (AOCL) (Details) (USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	($10,869)	[1]	($13,285)	[1]
Other comprehensive income before reclassifications	-4,269		1,524
Amounts reclassified from AOCL	659	[2]	892	[2]
Other Comprehensive (Loss) Income- Net of Tax	-3,610	[3]	2,416	[3]	-1,156	[3]
Ending balance	-14,479	[1]	-10,869	[1]	-13,285	[1]
Combined statutory tax rate	40.00%		41.00%		41.00%
Postretirement Liability Adjustment [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	-10,672	[1],[3]	-12,958	[1],[3]	-11,275	[3]
Other comprehensive income before reclassifications	-4,345		932
Amounts reclassified from AOCL	1,180	[2]	1,354	[2]
Other Comprehensive (Loss) Income- Net of Tax	-3,165	[3]	2,286	[3]	-1,683	[3]
Ending balance	-13,837	[1],[3]	-10,672	[1],[3]	-12,958	[1],[3]
Unrealized Gain (Loss) on Derivatives-Other [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	-594	[1],[3]	-621	[1],[3]	-648	[3]
Other comprehensive income before reclassifications	0		0
Amounts reclassified from AOCL	27	[2]	27	[2]
Other Comprehensive (Loss) Income- Net of Tax	27	[3]	27	[3]	27	[3]
Ending balance	-567	[1],[3]	-594	[1],[3]	-621	[1],[3]
Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Accumulated Other Comprehensive Income (Loss), Net of Tax [Roll Forward]
Beginning balance	397	[1],[3]	294	[1],[3]	-206	[3]
Other comprehensive income before reclassifications	76		592
Amounts reclassified from AOCL	-548	[2]	-489	[2]
Other Comprehensive (Loss) Income- Net of Tax	-472	[3]	103	[3]	500	[3]
Ending balance	($75)	[1],[3]	$397	[1],[3]	$294	[1],[3]
[1]	Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.
[2]	See table below.
[3]	Determined using a combined statutory tax rate of 40% in 2014 and 41% in 2013 and 2012.

ACCUMULATED_OTHER_COMPREHENSIV3

ACCUMULATED OTHER COMPREHENSIVE LOSS (AOCL) 2 (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest Charges									$17,872		$12,550		$12,427
Other Income & Expense									-5,560		-3,797		-2,617
Operations									102,428		85,805		78,425
Income Before Income Taxes									-101,378		-97,069		-91,952
Income Taxes	-9,455	-534	-2,379	-22,527	-11,322	-471	-2,269	-20,771	-34,895		-34,833		-33,711
Net Income	-24,041	-974	-3,811	-37,657	-21,953	-949	-3,821	-35,513	-66,483		-62,236		-58,241
Amounts Reclassified from AOCL [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Income Before Income Taxes									1,103		1,507
Income Taxes									444	[1]	615	[1]
Net Income									659		892
Amounts Reclassified from AOCL [Member] | Unrealized Loss on Derivatives-Other - Interest Rate Contracts designated as cash flow hedges [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Interest Charges									46		46
Amounts Reclassified from AOCL [Member] | Unrealized Gain (Loss) on Available-for-Sale Securities [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Other Income & Expense									-918		-828
Amounts Reclassified from AOCL [Member] | Postretirement Liability Adjustment [Member]
Reclassification out of Accumulated Other Comprehensive Income [Line Items]
Operations									$1,975		$2,289
[1]	Determined using a combined statutory tax rate of 40% and 41% in 2014 and 2013, respectively.

QUARTERLY_RESULTS_OF_OPERATION2

QUARTERLY RESULTS OF OPERATIONS - UNAUDITED (Details) (USD $)	3 Months Ended								12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Quarterly Financial Information Disclosure [Abstract]
Operating Revenues	$161,219	$60,952	$69,159	$210,545	$146,172	$59,674	$66,536	$174,098	$501,875	$446,480	$421,874
Expenses:
Cost of Sales (excluding depreciation)	79,644	23,400	24,879	103,293	71,654	24,717	26,108	77,602	231,216	200,081	188,710
Operations and Maintenance Including Fixed Charges	47,943	37,432	38,737	46,969	39,486	33,249	33,871	38,659
Income Taxes	9,455	534	2,379	22,527	11,322	471	2,269	20,771	34,895	34,833	33,711
Energy and Other Taxes	947	798	830	1,185	2,530	1,052	1,277	3,003	3,760	7,862	8,300
Total Expenses	137,989	62,164	66,825	173,974	124,992	59,489	63,525	140,035
Other Income and Expense	811	2,186	1,477	1,086	773	764	810	1,450
Net Income	$24,041	$974	$3,811	$37,657	$21,953	$949	$3,821	$35,513	$66,483	$62,236	$58,241

SCHEDULE_II_VALUATION_AND_QUAL1

SCHEDULE II - VALUATION AND QUALIFYING ACCOUNTS (Details) (Allowance for Doubtful Accounts [Member], USD $)	12 Months Ended
In Thousands, unless otherwise specified	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance	$4,553		$3,985		$3,060
Charged to Costs and Expenses	9,417		4,232		4,775
Charged to Other Accounts	-102	[1]	-41	[1]	110	[1]
Deductions	7,267	[2]	3,623	[2]	3,960	[2]
Balance	$6,601		$4,553		$3,985
[1]	Recoveries of accounts previously written off and minor adjustments.
[2]	Uncollectible accounts written off.