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Summary of Significant Accounting Policies - Additional Information (Detail) (USD $) | 12 Months Ended |  | 12 Months Ended | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | --- | --- | ---
Dec. 31, 2013 counterparty | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2013 13 to 24 months [Member] | Dec. 31, 2013 25 to 36 months [Member] | Dec. 31, 2013 37 to 60 months [Member] | Dec. 31, 2013 Minimum [Member] | Dec. 31, 2013 Maximum [Member] | Dec. 31, 2013 Building [Member] | Nov. 30, 2011 Barnett shale [Member] | Dec. 31, 2013 Proved oil and gas properties [Member] | Dec. 31, 2012 Proved oil and gas properties [Member] | Dec. 31, 2011 Proved oil and gas properties [Member] | Dec. 31, 2013 Unproved property leases [Member] | Dec. 31, 2012 Unproved property leases [Member] | Dec. 31, 2011 Unproved property leases [Member] | Dec. 31, 2013 Salt Water Disposal Facility [Member] | Dec. 31, 2013 Furniture and equipment [Member] Minimum [Member] | Dec. 31, 2013 Furniture and equipment [Member] Maximum [Member] | Dec. 31, 2013 Internal Revenue Service (IRS) [Member] | Dec. 31, 2013 State and Local Jurisdiction [Member]
Interest Cost Capitalized And Depreciation And Amortization Expenses For Property, Plant and Equipment [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Derivative, number of counterparties | 6 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Proceeds from sale of property | $ 0 | $ 0 | $ 2,202,000 |  |  |  |  |  |  | $ 2,202,000 |  |  |  |  |  |  |  |  |  |  |
Gain (loss) on sale of properties | 0 | 0 | (207,000) |  |  |  |  |  |  | (207,000) |  |  |  |  |  |  |  |  |  |  |
Impairment of oil and gas properties | 1,168,000 | 3,581,000 | 3,610,000 |  |  |  |  |  |  |  | 0 | 0 | 0 | 1,200,000 | 3,600,000 | 3,600,000 |  |  |  |  |
Capitalized interest costs | 4,600,000 | 3,300,000 | 3,100,000 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Estimated life of assets |  |  |  |  |  |  |  |  | 20 years |  |  |  |  |  |  |  | 30 years | 2 years | 7 years |  |
Past-due receivables from counterparties | 0 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Contractual commodity derivative volume, percent | 110.00% |  |  | 100.00% | 75.00% | 50.00% |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Restricted stock awards vesting period | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Annual Forfeiture Rate |  |  |  |  |  |  | 0.00% | 11.00% |  |  |  |  |  |  |  |  |  |  |  |  |
Stock-based compensation related to unrealized excess tax benefits |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4,800,000 | $ 3,500,000

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