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Fair Value Measurements - Additional Information (Details) - USD ($)
9 Months Ended
Sep. 30, 2015
Sep. 30, 2014
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Fair value assets transfer from Level 1 to Level 2 $ 0  
Fair value assets transfer from Level 2 to Level 1 0  
Fair value liabilities transfer from Level 1 to Level 2 0  
Fair value liabilities transfer from Level 2 to Level 1 0  
Level 3 [Member] | Fair Value on a Nonrecurring Basis [Member]    
Fair Value Assets And Liabilities Measured On Recurring And Nonrecurring Basis [Line Items]    
Impairment of oil and natural gas properties $ 0 $ 0