Quarterly report pursuant to Section 13 or 15(d)

Fair Value of Derivative Instruments on Condensed Consolidated Balance Sheets (Details)

v3.19.2
Fair Value of Derivative Instruments on Condensed Consolidated Balance Sheets (Details) - USD ($)
$ in Thousands
Jun. 30, 2019
Dec. 31, 2018
Derivatives, Fair Value [Line Items]    
Derivative assets $ 7,182 $ 34,932
Derivative liabilities 14,203 991
Derivative assets 2,756 10,100
Derivative Liability, Noncurrent 2,201 0
Derivative Liability 16,404 991
Derivative Asset 9,938 45,032
Commodity contracts    
Derivatives, Fair Value [Line Items]    
Derivative Liability 6,500  
Commodity contracts | Current Derivative Contract [Member]    
Derivatives, Fair Value [Line Items]    
Derivative assets 7,182 34,932
Derivative liabilities 14,203 991
Commodity contracts | Noncurrent Derivative Contract [Member]    
Derivatives, Fair Value [Line Items]    
Derivative assets 2,756 10,100
Derivative Liability, Noncurrent 2,201 0
Fair Value, Measurements, Recurring | Commodity contracts    
Derivatives, Fair Value [Line Items]    
Derivative assets 7,182 34,932
Derivative liabilities (14,203) (991)
Derivative assets 2,756 10,100
Derivative Liability, Noncurrent $ 2,201 $ 0