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Derivative Instruments - Effects of Gains and Losses from Derivative Instruments on Condensed Consolidated Financial Statements (Detail) - USD ($) $ in Thousands | 3 Months Ended
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Mar. 31, 2016 | Mar. 31, 2015
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | $ (416) | $ 580
Revenue [Member] | Derivatives not designated as hedging instruments [Member] | Forward Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (Loss) on derivatives | [1] | 1 | (125)
Cost of Sales [Member] | Derivatives not designated as hedging instruments [Member] | Propane Swap Agreement [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | 0 | 18
Cost of Sales [Member] | Derivatives designated as fair value hedges [Member] | Call Option [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | 0 | (81)
Cost of Sales [Member] | Derivatives designated as fair value hedges [Member] | Propane Swap Agreement [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | (364) |
Cost of Sales [Member] | Derivatives designated as fair value hedges [Member] | Put/Call Option [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | 73 | 506
Cost of Sales [Member] | Derivatives designated as fair value hedges [Member] | Future [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (Loss) on derivatives |  | 149 | 0
Inventories [Member] | Derivatives designated as fair value hedges [Member] | Put/Call Option [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (Loss) on derivatives |  | 0 | (3)
Other Comprehensive Income (Loss) [Member] | Derivatives designated as fair value hedges [Member] | Propane Swap Agreement [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (Loss) on derivatives |  | 0 | (12)
Other Comprehensive Income (Loss) [Member] | Derivatives designated as fair value hedges [Member] | Future [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Gain (Loss) on derivatives |  | (462) | 0
Options [Member] | Revenue [Member] | Forward Contracts [Member] |  |  |
Derivative Instruments, Gain (Loss) [Line Items] |  |  |
Derivative, Gain (Loss) on Derivative, Net |  | $ 187 | $ 277
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- Definition Amount of increase (decrease) in the fair value of derivatives recognized in the income statement. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5618551-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -Subparagraph (a),(c),(d),(e) -URI http://asc.fasb.org/extlink&oid=56946850&loc=SL5624171-113959 + 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 The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=56944662&loc=d3e3602-108585 + Details
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