v2.4.0.8
Contingencies (Narrative) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 6 Months Ended
Jun. 30, 2014
occurrence
plaintiffs
Jun. 30, 2014
plaintiffs
Mar. 31, 2009
mi
Oil and Gas Delivery Commitments and Contracts [Line Items]      
Distance from original drilling location in miles     95
Payments for leg and debris removal $ 6.4    
Loss Contingency, Damages Sought, Value 5.0    
Civil litigation claim damages for cost of repair and business interruption due to pipeline rupture 26.0 26.0  
Liability insurance self-insured retention per occurrence 10.0 10.0  
Annual liability coverage limit for wreckage and debris removal costs   490.0  
Liability insurance self-insured retention 15.0 15.0  
Number of Occurrences 2    
Liability insurance self insured retention for each occurrence thereafter 1.0    
Litigation Settlement, Amount 9.6 3.2  
Legal Fees   3.6  
Number of plaintiffs 100 100  
Loss Contingency, Claims Settled, Number 58    
Letters of Credit Outstanding, Amount 248.4 248.4  
Ensco 29 [Member]
      
Oil and Gas Delivery Commitments and Contracts [Line Items]      
Annual liability coverage limit for wreckage and debris removal costs $ 3.8