Quarterly report pursuant to Section 13 or 15(d)

Contingencies - Additional Information (Details)

v3.19.1
Contingencies - Additional Information (Details)
 3 Months Ended 12 Months Ended
Mar. 31, 2019
USD ($)
claim
Mar. 31, 2018
USD ($)
Dec. 31, 2018
USD ($)
May 31, 2017
USD ($)
Jan. 27, 2017
USD ($)
Dec. 15, 2014
DeepwaterWell
Dec. 31, 2010
USD ($)
Loss Contingencies [Line Items]              
Number of deepwater wells abandoned | DeepwaterWell           3  
Deposit Into registry of court $ 49,500,000   $ 49,500,000        
Loss contingency accrued amount 49,500,000   49,500,000        
Notified disallowed amount in reductions taken by ONRR         $ 4,700,000   $ 4,700,000
Bond requied to post in order to appeal         7,200,000    
Cash collateral required to appeal         $ 6,900,000    
Liability reserve $ 2,200,000   2,100,000        
Royalty payment processing revised period 84 months            
Royalties paid $ 100,000 $ 100,000          
BSEE              
Loss Contingencies [Line Items]              
Loss contingency accrued amount $ 3,400,000   3,400,000        
Number of notices | claim 9            
Proposed civil penalties related to various incidents of noncompliance, total $ 7,700,000            
Payments for civil penalty 0 $ 0          
Apache Corporation | Judicial Ruling              
Loss Contingencies [Line Items]              
Amount owed to Apache under judicial decision       $ 43,200,000      
Prejudgment interest, attorney fees and judgment costs       $ 6,300,000      
Apache Corporation | Judicial Ruling | Other Noncurrent Assets              
Loss Contingencies [Line Items]              
Deposit Into registry of court 49,500,000   49,500,000        
Apache Corporation | Judicial Ruling | Other Noncurrent Liabilities              
Loss Contingencies [Line Items]              
Loss contingency accrued amount $ 49,500,000   $ 49,500,000