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Derivative Instruments and Risk Management - Summary of Commodity Swaps (Parenthetical) (Detail) | Jun. 30, 2013 T | Dec. 31, 2012 T
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Derivative Instruments And Hedging Activities Disclosure [Abstract] |  |
Commodity swaps, notional quantity | 25 | 275

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- Definition Aggregate notional amount of derivative expressed in nonmonetary units. For example, the number of barrels specified in a fuel oil forward purchase contract. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Article 12 -Section 13 -Sentence Column B + Details
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- Details
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