Quarterly report pursuant to Section 13 or 15(d)

INVESTMENT IN AMAK (Details)

v3.5.0.2
INVESTMENT IN AMAK (Details)
$ / shares in Units, $ in Thousands
3 Months Ended 9 Months Ended
Jul. 31, 2016
$ / shares
shares
Sep. 30, 2016
USD ($)
SAR / $
Sep. 30, 2015
USD ($)
Sep. 30, 2016
USD ($)
SAR / $
Sep. 30, 2015
USD ($)
Jul. 31, 2016
SAR / shares
shares
Jun. 30, 2016
Dec. 31, 2015
USD ($)
Schedule of Equity Method Investments [Line Items]                
Equity in earnings (loss) of AMAK   $ (2,089) $ (2,054) $ 5,079 $ (2,364)      
Results of Operations [Abstract]                
Loss from operations   4,128 11,063 16,169 30,287      
AMAK [Member]                
Related Party Transaction [Line Items]                
Investment in AMAK   $ 52,800   $ 52,800       $ 47,700
AMAK [Member]                
Schedule of Equity Method Investments [Line Items]                
Percentage investment in AMAK 33.44% 33.44%   33.44%   33.44% 35.25% 35.25%
Exchange rate | SAR / $   3.75   3.75        
Company's share of income (loss) reported by AMAK   $ (2,426) (2,391) $ 4,068 (3,375)      
Amortization of difference between Company's investment in AMAK and Company's share of net assets of AMAK   337 337 1,011 1,011      
Equity in earnings (loss) of AMAK   (2,089) (2,054) 5,079 (2,364)      
Shares issued (in shares) | shares 4,000,000              
Results of Operations [Abstract]                
Sales   318 19,874 9,921 38,458      
Gross profit (loss)   (4,747) (2,711) (7,556) 35      
General, administrative and other expenses   2,796 4,067 6,986 9,605      
Loss from operations   (7,543) (6,778) (14,542) (9,570)      
Gain on settlement with former operator   14 0 25,434 0      
Net income (loss)   (7,529) (6,778) 10,892 (9,570)      
Depreciation, depletion and amortization   3,200 4,200 8,600 15,300      
Net income (loss) before depreciation and amortization   (4,341) $ (2,543) 19,498 $ 5,680      
Financial Position [Abstract]                
Current assets   35,153   35,153       $ 26,078
Noncurrent assets   260,142   260,142       259,527
Total assets   295,295   295,295       285,605
Current liabilities   2,883   2,883       22,740
Long term liabilities   87,994   87,994       89,364
Shareholders' equity   204,418   204,418       173,501
Total liabilities and Shareholders' equity   $ 295,295   $ 295,295       $ 285,605
Arab Mining Co [Member]                
Schedule of Equity Method Investments [Line Items]                
Shares issued (in shares) | shares 3,750,000              
Share price (in dollars per share) | (per share) $ 5.33         SAR 20.00    
Shares reserved for future issuance (in shares) | shares 250,000         250,000