Commodity Derivative Instruments (Schedule of Commodity Derivative Contracts) (Details)
6 Months Ended
Feb. 28, 2014
Contract One [Member] | Collar [Member]
 
Derivatives, Fair Value [Line Items]  
Quantity (Bbl/month) 1,840
Strike/Swap Price ($/Bbl), minimum 85.00
Strike/Swap Price ($/Bbl), maximum 98.50
Term, minimum Mar. 01, 2014
Term, maximum Dec. 31, 2014
Contract One [Member] | Swap [Member]
 
Derivatives, Fair Value [Line Items]  
Quantity (Bbl/month) 22,240
Strike/Swap Price ($/Bbl) 95.17
Term, minimum Mar. 01, 2014
Term, maximum Dec. 31, 2014
Contract Two [Member] | Collar [Member]
 
Derivatives, Fair Value [Line Items]  
Quantity (Bbl/month) 20,000
Strike/Swap Price ($/Bbl), minimum 87.00
Strike/Swap Price ($/Bbl), maximum 96.25
Term, minimum Mar. 01, 2014
Term, maximum Dec. 31, 2014
Contract Three [Member] | Collar [Member]
 
Derivatives, Fair Value [Line Items]  
Quantity (Bbl/month) 7,000
Strike/Swap Price ($/Bbl), minimum 80.00
Strike/Swap Price ($/Bbl), maximum 92.50
Term, minimum Jan. 01, 2015
Term, maximum Jun. 30, 2015
Contract Four [Member] | Collar [Member]
 
Derivatives, Fair Value [Line Items]  
Quantity (Bbl/month) 2,500
Strike/Swap Price ($/Bbl), minimum 80.00
Strike/Swap Price ($/Bbl), maximum 95.75
Term, minimum Jan. 01, 2015
Term, maximum Jun. 30, 2015
Contract Five [Member] | Collar [Member]
 
Derivatives, Fair Value [Line Items]  
Quantity (Bbl/month) 9,000
Strike/Swap Price ($/Bbl), minimum 80.00
Strike/Swap Price ($/Bbl), maximum 92.25
Term, minimum Jul. 01, 2015
Term, maximum Dec. 31, 2015