Quarterly report pursuant to Section 13 or 15(d)

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

v3.8.0.1
Reportable Segments - Results of Operations by Reportable Segment (Detail) - USD ($)
$ in Thousands
 3 Months Ended
Mar. 31, 2018
Mar. 31, 2017
Revenues:    
Revenues $ 109,675 $ 98,271
Operating gross margin:    
Total operating gross margin (10,408) (19,745)
General and administrative expense (6,201) (7,040)
Gain (loss) on disposition of assets, net 343 (352)
Total operating income (loss) (16,266) (27,137)
Interest expense (11,240) (10,870)
Interest income 23 10
Other 291 530
Income (loss) before income taxes (27,192) (37,467)
Exxon Neftegas Limited    
Operating gross margin:    
Reimbursement revenue $ 12,100 $ 13,000
Exxon Neftegas Limited | Customer Concentration Risk | Sales Revenue, Net    
Operating gross margin:    
Percentage of revenue from major customer 28.60% 34.90%
Exxon Neftegas Limited | Customer Concentration Risk | Sales Revenue, Net Of Reimbursable Revenues    
Operating gross margin:    
Percentage of revenue from major customer 20.10% 25.70%
BP Exploration Alaska, Inc. | Customer Concentration Risk | Sales Revenue, Net    
Operating gross margin:    
Percentage of revenue from major customer   11.30%
Total Rental Tools Services    
Revenues:    
Revenues $ 52,225 $ 33,843
Operating gross margin:    
Total operating gross margin 216 (10,734)
U.S. Rental Tools    
Revenues:    
Revenues 34,748 20,231
Operating gross margin:    
Total operating gross margin 4,231 (3,773)
International Rental Tools    
Revenues:    
Revenues 17,477 13,612
Operating gross margin:    
Total operating gross margin (4,015) (6,961)
Total Drilling Services    
Revenues:    
Revenues 57,450 64,428
Operating gross margin:    
Total operating gross margin (10,624) (9,011)
U.S. (Lower 48) Drilling    
Revenues:    
Revenues 1,354 1,215
Operating gross margin:    
Total operating gross margin (5,288) (7,226)
International & Alaska Drilling    
Revenues:    
Revenues 56,096 63,213
Operating gross margin:    
Total operating gross margin $ (5,336) $ (1,785)
International & Alaska Drilling | Exxon Neftegas Limited | Customer Concentration Risk | Sales Revenue, Net    
Operating gross margin:    
Percentage of revenue from major customer 55.90% 54.30%
International & Alaska Drilling | Exxon Neftegas Limited | Customer Concentration Risk | Sales Revenue, Net Of Reimbursable Revenues    
Operating gross margin:    
Percentage of revenue from major customer 45.90% 44.40%
International & Alaska Drilling | BP Exploration Alaska, Inc. | Customer Concentration Risk | Sales Revenue, Net Of Reimbursable Revenues    
Operating gross margin:    
Percentage of revenue from major customer   17.60%