Quarterly report pursuant to Section 13 or 15(d)

General - Additional Information (Detail)

v3.7.0.1
General - Additional Information (Detail)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
USD ($)
Jun. 30, 2016
USD ($)
Jun. 30, 2017
USD ($)
segment
Jun. 30, 2016
USD ($)
Dec. 31, 2016
USD ($)
Revenue, Major Customer [Line Items]          
Number of Reportable Segments | segment     4    
Payments to Acquire Property, Plant, and Equipment | $     $ 26,559 $ 16,257  
Percentage accounted for under the equity method 50.00%   50.00%    
Reimbursable Costs | $ $ 15,200 $ 18,900 $ 30,500 $ 37,900  
Deposits in domestic bank | $ 106,300   106,300   $ 81,400
Deposits, Foreign | $ $ 40,400   $ 40,400   $ 39,700
Exxon Neftegas Limited [Member]          
Revenue, Major Customer [Line Items]          
Percentage of revenue from major customer     34.00% 39.80%  
Reimbursement Revenue | $     $ 27,000 $ 36,900  
Concentration Risk, Other Risk     0.246 0.287  
BP Exploration Alaska, Inc. [Member]          
Revenue, Major Customer [Line Items]          
Percentage of revenue from major customer     10.50%    
Drilling Services [Member] | U.S. Operations [Member]          
Revenue, Major Customer [Line Items]          
Number of Reportable Segments | segment     2    
Drilling Services [Member] | International Operations [Member]          
Revenue, Major Customer [Line Items]          
Number of Reportable Segments | segment     2    
Drilling Services [Member] | International Operations [Member] | Exxon Neftegas Limited [Member]          
Revenue, Major Customer [Line Items]          
Percentage of revenue from major customer     57.00% 58.40%  
Concentration Risk, Other Risk     0.467 0.464  
Drilling Services [Member] | International Operations [Member] | BP Exploration Alaska, Inc. [Member]          
Revenue, Major Customer [Line Items]          
Percentage of revenue from major customer     17.60%    
Rental Tools [Member] | U.S. Operations [Member]          
Revenue, Major Customer [Line Items]          
Number of Reportable Segments | segment     2    
Rental Tools [Member] | International Operations [Member]          
Revenue, Major Customer [Line Items]          
Number of Reportable Segments | segment     2