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Subsequent Events (Narrative) (Detail) (USD $) In Millions, unless otherwise specified |  | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2012 Maximum [Member] Amended Credit Facility [Member] EBITDAX [Member] | Sep. 30, 2012 Minimum [Member] Amended Credit Facility [Member] Current Ratio [Member] | Oct. 02, 2012 Subsequent Event [Member] Amended Credit Facility [Member] | Oct. 31, 2012 2012 Two-Way And Three-Way Collars [Member] Subsequent Event [Member] bbl | Oct. 31, 2012 2013 Two-Way And Three-Way Collars [Member] Subsequent Event [Member] bbl | Oct. 31, 2012 2014 Two-Way And Three-Way Collars [Member] Subsequent Event [Member] bbl
Subsequent Event [Line Items] |  |  |  |  |  |
Increase in aggregate commitment |  |  | $ 750 |  |  |
Maximum debt to EBITDAX ratio | 4 |  |  |  |  |
Minimum current ratio |  | 1.0 |  |  |  |
Maximum EBITDAX to Interest Expense ratio |  |  | 2.5 |  |  |
Total notional amount, in barrels |  |  |  | 668,000 | 396,000 | 31,000

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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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- Definition The aggregate commitment may be increased to this amount by increasing the commitment of one or more lender(s) under the credit facility. + References No definition available. + Details
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- Definition The maximum ratio of Total Net Debt to consolidated EBITDAX as required by the entity's debt agreement. + References No definition available. + Details
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- Definition The minimum current ratio as required by the entity's debt agreement. + References No definition available. + Details
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- Definition The maximum ratio of consolidated EBITDAX to consolidated Interest Expense as required by the entity's debt agreement. + References No definition available. + Details
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- Details
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