Annual report pursuant to Section 13 and 15(d)

Property and Equipment - Narrative (Details)

v3.6.0.2
Property and Equipment - Narrative (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Dec. 31, 2013
Property, Plant and Equipment [Line Items]        
Impairment of oil and gas properties $ 715,495 $ 1,440,418 $ 0  
Cumulative capitalization of general and administrative costs incurred and capitalized to the full cost pool 129,900 100,600    
Capitalized general and administrative costs 29,300 27,900 $ 25,200  
Capitalized costs of oil and natural gas properties excluded from amortization $ 1,580,305 $ 1,817,701   $ 575,521
Minimum        
Property, Plant and Equipment [Line Items]        
Expected number of years amortization will commence 3 years      
Maximum        
Property, Plant and Equipment [Line Items]        
Expected number of years amortization will commence 5 years