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Goodwill (Details) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 30, 2016
Sep. 30, 2017
Sep. 30, 2016
Dec. 31, 2016
Goodwill [Line Items]          
Goodwill $ 0   $ 0   $ 62,041
Impairment of goodwill 75,121 $ 0 75,121 $ 0  
Delaware Basin Acquisition [Member]          
Goodwill [Line Items]          
Goodwill $ 75,121   $ 75,121   $ 62,041