Quarterly report pursuant to Section 13 or 15(d)

Property And Equipment (Summary Of Oil And Gas Properties Not Subject To Amortization) (Details)

v3.3.0.814
Property And Equipment (Summary Of Oil And Gas Properties Not Subject To Amortization) (Details) - USD ($)
$ in Thousands
Sep. 30, 2015
Dec. 31, 2014
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]    
Total oil and gas properties not subject to amortization, total $ 2,018,803 $ 1,465,538
Colorado [Member]    
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]    
Total oil and gas properties not subject to amortization, total 5,088  
Bakken [Member]    
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]    
Total oil and gas properties not subject to amortization, total 96  
Southern Louisiana [Member]    
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]    
Total oil and gas properties not subject to amortization, total 342  
Ohio [Member]    
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]    
Total oil and gas properties not subject to amortization, total 2,013,232  
Other [Member]    
Capitalized Costs of Unproved Properties Excluded from Amortization [Line Items]    
Total oil and gas properties not subject to amortization, total $ 45