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Number of contract years entered into by the entity with a developer to design, build, own and operate a district energy system and central energy center for a project

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Number of years in expected delay in specific construction project, at lower range.

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

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SJI has guaranteed certain obligations of BC Landfill Energy, LLC (BCLE) and WC Landfill Energy, LLC (WCLE), unconsolidated joint ventures in which Marina has a 50% equity interest through Energenic. BCLE and WCLE have entered into agreements ranging from 15-20 years with the respective county governments to lease and operate facilities that will produce electricity from landfill methane gas

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The non current amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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SJI provided support to LVE to cover interest and other project related costs.

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Amount of letter of credit provided by the developer for costs to support its monthly payment obligation to the entity.

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Amount of maximum capital risk of the entity that may include equity contributions, letters of credit and the unsecured notes receivable.

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

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Number of unions that represent employees covered by collective bargaining agreements.

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These guarantees generally expire within the next two years and were issued to enable our subsidiary to market retail natural gas.

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Percentage of personnel represented by collective bargaining agreements.

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Approximate term of the guarantee or each group of similar guarantees, in lower range.

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Developers, builders, governmental agencies and municipalities will provide the entity with cash, or in some cases property, to extend its services to their properties. Nonrefundable contributions are recorded as contributions in aid of construction ("CIAC").

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Amount paid during the reporting period into the sinking fund.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Reflects when the credit facility terminates, which may be presented in a variety of ways (year, month and year, day, month and year, quarter).

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

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Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

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Amounts due from parties associated with the reporting entity as evidenced by a written promise to pay, due within 1 year (or 1 business cycle).

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COMMITMENTS AND CONTINGENCIES (Details) (USD $)	6 Months Ended
COMMITMENTS AND CONTINGENCIES (Details) (USD $)	Jun. 30, 2011	May 31, 2011	Dec. 31, 2010	Jun. 30, 2011 LVE Energy Partners [Member]	Apr. 30, 2007 LVE Energy Partners [Member]	Jun. 30, 2011 Energenic [Member]	Jun. 30, 2011 Parental Guarantee [Member]	Jun. 30, 2011 Letter of Credit, Banks [Member]	Jun. 30, 2011 Letter of Credit, Developer [Member]	Jun. 30, 2011 Standby Letter of Credit [Member]	Jun. 30, 2011 Standby Letter of Credit, Variable-rate Demand Bonds [Member]	Jun. 30, 2011 Standby Letter of Credit, Market Retail Electricity [Member]	Jun. 30, 2011 Letter of Credit, Separate Facility [Member]	Jun. 30, 2011 ACR Energy Partners LLC [Member]
Guarantees [Abstract]
Liability recorded related to guarantees	$ 1,900,000			$ 1,600,000
Equity interest (in hundredths)					50.00%	50.00%								50.00%
Contract with a resort developer (in years)					25									20
Expected delay in construction (in years), lower range		3
Expected delay in construction (in years), upper range		5
Outstanding balance of bank debt	426,400,000		340,000,000	220,400,000
Letter of credit from developer	6,000,000
Letter of credit provided	550,437,000							10,000,000	5,000,000	102,900,000	62,300,000	40,600,000	25,200,000
Notes receivable - affiliate	8,372,000		1,183,000	55,000,000
Maximum capital risk	69,300,000
Interest and other project related costs	4,900,000
Guaranteed amount				20,000,000			4,700,000
Term of guaranteed obligations, lower range (in years)	15
Term of guaranteed obligations, upper range (in years)	20
Maximum amount of obligation under guarantee contracts	4,200,000
Term of guarantee (in years)							2
Capital contribution obligation [Abstract]
Capital contributions to ACR														42,000,000
Debt service reserve fund created by Marina to ACR														$ 2,800,000
Collective bargaining agreements [Abstract]
Percentage of personnel represented by collective bargaining agreements (in hundredths)	50.00%
Number of unions	2
Standby letters of credit [Abstract]
Expiration date	August 2015
Environmental remediation costs [Abstract]
Number of sites for environmental cleanup (in number of sites)	12