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Derivative Instruments - Fair Values of Derivative Contracts Recorded in Condensed Consolidated Balance Sheet (Detail) - USD ($) $ in Thousands | Mar. 31, 2016 | Dec. 31, 2015
--- | --- | ---
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contract Liabilities, Current | $ 423 | $ 433
Energy Marketing Contracts Assets, Current | 0 | 153
Mark To Market Energy Assets [Member] | Forward Contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contracts Assets, Current | $ 0 | 1
Mark To Market Energy Assets [Member] | Put Option [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contracts Assets, Current |  |
Mark To Market Energy Assets [Member] | Put Option [Member] | Derivatives designated as fair value hedges [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Derivative Asset, Fair Value, Amount Not Offset Against Collateral |  | 152
Mark To Market Energy Assets [Member] | Future [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contract Liabilities, Current |  | 423
Mark-to-market energy liabilities [Member] | Forward Contracts [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contract Liabilities, Current | $ 0 | 1
Mark-to-market energy liabilities [Member] | Propane Swap Agreement [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contract Liabilities, Current | 0 | 323
Mark-to-market energy liabilities [Member] | Future [Member] |  |
Derivatives, Fair Value [Line Items] |  |
Energy Marketing Contract Liabilities, Current | $ 423 | $ 109

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- Definition Fair value, after offset of derivative liability, of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, before offset against an obligation to return collateral under a master netting arrangement. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 9 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226006-175313 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=56946850&loc=d3e41678-113959 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Current liabilities attributable to energy marketing activities (trading activities). Current energy marketing (trading activities) are when entities engage in both financial and physical trading to increase profits, manage their commodity price risk and enhance system reliability. They may trade electricity, coal, natural gas and oil. These entities typically use a variety of financial instruments, including forward contracts, options and swaps. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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- Definition Carrying amount as of the balance sheet date of the asset arising from energy trading activities that involves the purchase and sale of energy under forward contracts at fixed and variable prices and the buying and selling of financial energy contracts that include exchange futures and options and over the counter options and swaps, which are expected to be converted into cash or otherwise disposed of within a year or the normal operating cycle, if longer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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