v2.4.0.8
Nature of Business (Details)
 12 Months Ended
Dec. 31, 2013
Shelf Drilling Holdings, Ltd
drillingunit
Dec. 31, 2013
Continuing operations
drillingunit
Nov. 30, 2012
Discontinued operations
drillingunit
Dec. 31, 2013
Discontinued operations
Shelf Drilling Holdings, Ltd
Dec. 31, 2013
Discontinued operations
Shelf Drilling Holdings, Ltd
Minimum
Dec. 31, 2013
Discontinued operations
Shelf Drilling Holdings, Ltd
Maximum
Number of mobile offshore drilling units   79        
Number of High-Specification Floaters (in drilling units)   46        
Number of Midwater Floaters (in drilling units)   22        
Number of High-Specification Jackups (in drilling units)   11        
Number of Ultra-Deepwater drillships under construction (in drilling units)   7        
Number of High-Specification Jackup under construction (in drilling units)   5        
Number of Standard Jackups (in drilling units) 7          
Number of Standard Jackups sold (in drilling units)     37      
Number of swamp barge sold (in drilling units)     1      
Period for which Standard Jackups are agreed to be operated under operating agreements         9 months 27 months
Maximum period for which transition services to be provided following the completion of the sale transactions       18 months