v2.4.0.8
Discontinued Operations (Narrative) (Details) (USD $)
In Millions, unless otherwise specified
 3 Months Ended 6 Months Ended
Jun. 30, 2014
rigs
Jun. 30, 2013
Jun. 30, 2014
Jun. 30, 2013
Dec. 31, 2013
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Number Of Rigs Committed To Be Sold 5        
Impairment of Long-Lived Assets to be Disposed of, Net of Tax Benefit $ 508.8 $ 0 $ 508.8 $ 0  
Debt Instrument Carrying Value 4,726.6   4,726.6   4,766.4
ENSCO 85 [Member]
          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Net proceeds from rig sale 64.4        
Gain (Loss) on Disposition of Property Plant Equipment 2.3   2.3    
ENSCO 69 And Wisconsin [Member]
          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Net proceeds from rig sale     32.2    
Gain (Loss) on Disposition of Property Plant Equipment 17.9   17.9    
Pride Pennsylvania [Member]
          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Net proceeds from rig sale       15.5  
Gain (Loss) on Disposition of Property Plant Equipment       (1.1)  
6.36% MARAD bonds, including current maturities, due 2015 [Member]
          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Debt instrument, interest rate, stated percentage 6.36%   6.36%   6.36%
Debt Instrument Carrying Value 19.0   19.0   25.3
6.36% MARAD bonds due 2015 [Member]
          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Debt instrument, interest rate, stated percentage 6.36%   6.36%    
Debt, Current 12.7   12.7    
Discontinued Operations [Member]
          
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]          
Impairment of Long-Lived Assets to be Disposed of, Net of Tax Benefit 508.8        
Impairment of Long-Lived Assets to be Disposed of, Tax Benefit $ 37.6