XML 30 R81.htm IDEA: XBRL DOCUMENT v2.4.0.8
Business Segments - Additional Information (Detail) (USD $)
 12 Months Ended
Dec. 31, 2013
Customer
Dec. 31, 2012
Customer
Dec. 31, 2011
Customer
Segment Reporting Disclosure [Line Items]      
Number of reportable business segments 3    
Marketable land-based drilling rigs 279    
Long-lived assets $ 3,635,541,000 $ 3,615,383,000  
Major Customer
      
Segment Reporting Disclosure [Line Items]      
Revenues 286,000,000    
Number of customers accounted for 10% or more of consolidated revenues 1 0 0
Major Customer | Revenues
      
Segment Reporting Disclosure [Line Items]      
Percentage of sales revenues 10.50%    
Canada | Contract Drilling
      
Segment Reporting Disclosure [Line Items]      
Oil and gas services 86,600,000 79,400,000 106,000,000
Long-lived assets $ 69,100,000 $ 72,600,000