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Property and Equipment - Additional Information (Detail) - USD ($)
$ in Millions
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2017
Property Plant And Equipment [Line Items]    
Future net cash flow discount rate   10.00%
Impairment expense related to oil and natural gas properties $ 1.7 $ 2.2
Drilling Rigs That Would No Longer Be Marketed As Rigs    
Property Plant And Equipment [Line Items]    
Impairment charge for the write-down of drilling equipment $ 29.0