Quarterly report pursuant to Section 13 or 15(d)

Organization and Accounting Policies (Narrative1) (Detail)

v3.5.0.2
Organization and Accounting Policies (Narrative1) (Detail) - USD ($)
 3 Months Ended 6 Months Ended
Jun. 30, 2016
Dec. 31, 2015
Jun. 30, 2015
Jun. 30, 2016
Jun. 30, 2015
Error Corrections and Prior Period Adjustments Restatement [Line Items]          
Current Income Tax Expense (Benefit)       $ 0  
Net Income Loss $ (261,000)   $ (5,204,000) (8,324,000) $ (44,209,000)
Angola [Member]          
Error Corrections and Prior Period Adjustments Restatement [Line Items]          
Current Income Tax Expense (Benefit) $ 100,000     $ 3,100,000  
Overstated [Member] | Angola [Member]          
Error Corrections and Prior Period Adjustments Restatement [Line Items]          
Allowance For Doubtful Accounts Receivable   $ 7,600,000      
Group 42-BLR Group [Member]          
Error Corrections and Prior Period Adjustments Restatement [Line Items]          
Legal expense   $ 350,000