XML 39 R28.htm IDEA: XBRL DOCUMENT v3.8.0.1
Acquisitions and Divestitures - Narrative (Details)
shares in Millions
9 Months Ended
Aug. 09, 2017
USD ($)
a
shares
Jul. 14, 2017
USD ($)
Jul. 11, 2017
USD ($)
Sep. 30, 2017
USD ($)
Sep. 30, 2016
USD ($)
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]          
Closing purchase price of acquired oil and gas properties $ 3,400,000        
Proceeds from the sale of oil and gas properties       $ 15,098,000 $ 13,571,000
Net mineral acres acquired | a 973        
Issuance of stock for acquisition of oil and gas properties | shares 2.0        
Ward County, TX [Member]          
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]          
Closing purchase price of acquired oil and gas properties     $ 20,900,000    
Powder River Basin [Member]          
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]          
Proceeds from the sale of oil and gas properties   $ 4,600,000      
Gain (loss) on sale of oil and gas property   $ 0      
Bone Spring and Wolfcamp [Member]          
Costs Incurred, Oil and Gas Property Acquisition, Exploration, and Development Activities [Line Items]          
Net mineral acres acquired | a 853