Quarterly report pursuant to Section 13 or 15(d)

Reportable Segments - Results of Operations by Reportable Segment (Detail)

v3.7.0.1
Reportable Segments - Results of Operations by Reportable Segment (Detail) - USD ($)
$ in Thousands
 3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Revenues:        
Revenues $ 109,607 $ 105,287 $ 207,878 $ 235,790
Operating gross margin:        
Total operating gross margin (11,016) (20,225) (30,761) (33,653)
General and administrative expense (6,503) (7,995) (13,543) (17,776)
Provision for reduction in carrying value of certain assets       (1,088)
Gain (loss) on disposition of assets, net (113) (2) (465) (62)
Total operating income (loss) (17,632) (28,222) (44,769) (51,491)
Interest expense (11,095) (12,187) (21,965) (23,749)
Interest income 22 32 32 39
Other 560 (358) 1,090 2,127
Income (loss) before income taxes (28,145) (40,735) $ (65,612) $ (73,074)
Exxon Neftegas Limited [Member]        
Segment Reporting Information [Line Items]        
Concentration Risk, Other Risk     0.246 0.287
Percentage of revenue from major customer     34.00% 39.80%
Reimbursement Revenue     $ 27,000 $ 36,900
BP Exploration Alaska, Inc. [Member]        
Segment Reporting Information [Line Items]        
Percentage of revenue from major customer     10.50%  
Drilling Services [Member]        
Revenues:        
Revenues 65,711 72,991 $ 130,138 163,695
Operating gross margin:        
Total operating gross margin (7,316) (5,815) (16,316) (9,297)
Drilling Services [Member] | U.S. Operations [Member]        
Revenues:        
Revenues 5,042 1,065 6,257 3,150
Operating gross margin:        
Total operating gross margin (4,528) (9,011) (11,761) (17,571)
Drilling Services [Member] | International Operations [Member]        
Revenues:        
Revenues 60,669 71,926 123,881 160,545
Operating gross margin:        
Total operating gross margin (2,788) 3,196 $ (4,555) $ 8,274
Drilling Services [Member] | Exxon Neftegas Limited [Member] | International Operations [Member]        
Segment Reporting Information [Line Items]        
Concentration Risk, Other Risk     0.467 0.464
Percentage of revenue from major customer     57.00% 58.40%
Drilling Services [Member] | BP Exploration Alaska, Inc. [Member] | International Operations [Member]        
Segment Reporting Information [Line Items]        
Percentage of revenue from major customer     17.60%  
Rental Tools [Member]        
Revenues:        
Revenues 43,896 32,296 $ 77,740 $ 72,095
Operating gross margin:        
Total operating gross margin (3,700) (14,410) (14,445) (24,356)
Rental Tools [Member] | U.S. Operations [Member]        
Revenues:        
Revenues 29,704 17,961 49,936 40,516
Operating gross margin:        
Total operating gross margin 2,988 (5,472) (798) (9,422)
Rental Tools [Member] | International Operations [Member]        
Revenues:        
Revenues 14,192 14,335 27,804 31,579
Operating gross margin:        
Total operating gross margin $ (6,688) $ (8,938) $ (13,647) $ (14,934)