v3.3.1.900

Derivative Instruments and Fair Value Measurements - Summary of Change in Fair Value of Commodity Derivatives (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
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Dec. 31, 2015 | Sep. 30, 2015 | Jun. 30, 2015 | Mar. 31, 2015 | 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, 2015 | Dec. 31, 2014 | Dec. 31, 2013
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gain (loss) on commodity derivatives | $ 14,552 | $ 12,755 | $ 9,281 | $ 15,901 | $ 7,782 | $ (764) | $ (3,320) | $ (1,339) | $ 199 | $ (840) | $ (714) | $ 307 | $ 52,489 | $ 2,359 | $ (1,048)
Derivatives Not Designated as Hedging Instruments [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gain (loss) on commodity derivatives |  |  |  |  |  |  |  |  |  |  |  |  | 19,275 | 44,472 | (5,644)
Derivatives Not Designated as Hedging Instruments [Member] | Unrealized Gain (Loss) on Commodity Derivatives [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gain (loss) on commodity derivatives |  |  |  |  |  |  |  |  |  |  |  |  | (33,214) | 42,113 | (4,596)
Derivatives Not Designated as Hedging Instruments [Member] | Realized Gain (Loss) on Commodity Derivatives [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivatives, Fair Value [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total gain (loss) on commodity derivatives |  |  |  |  |  |  |  |  |  |  |  |  | $ 52,489 | $ 2,359 | $ (1,048)

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- Definition Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects. + 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 + Details
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