INVESTMENT IN AL MASANE AL KOBRA MINING COMPANY (AMAK) (Details)	12 Months Ended				1 Months Ended		12 Months Ended					1 Months Ended
	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)	Dec. 31, 2014 SAR	May 31, 2013 AMAK [Member] USD ($)	Jul. 31, 2011 AMAK [Member] Member	Dec. 31, 2014 AMAK [Member] USD ($)	Dec. 31, 2013 AMAK [Member] USD ($)	Dec. 31, 2012 AMAK [Member] USD ($)	Dec. 31, 2014 AMAK [Member] SAR	Dec. 31, 2013 AMAK [Member] SAR	Jul. 31, 2011 AMAK [Member] Saudi Investors [Member]	Jul. 31, 2011 AMAK [Member] ARMICO [Member] USD ($)
Investment in Al Masane Al Kobra Mining Company Amak [Line Items]
Investment in AMAK							$ 53,000,000	$ 54,100,000
Cash contributed by other investors to AMAK													37,300,000
Exchange rate				3.75						3.75
Percentage interest acquire by other investors in AMAK (in hundredths)								10.00%				53.00%	10.00%
Shares purchased under equity method investments (in shares)								937,500
Share price (in dollars per share)								$ 8.00			30
Payments to acquire equity method investments								7,500,000
Number of board members can be appointed by entity						4
Maximum number of board members as per by laws						9
Gain upon formation of AMAK							16,200,000
Percentage investment in AMAK (in hundredths)						37.00%		35.00%
Number of shares acquired in joint venture by other investors (in shares)													5,000,000
Results of Operations [Abstract]
Sales							63,300,000	104,990,000	15,594,000
Gross Profit							3,624,000	21,881,000	3,825,000
General, administrative and other expenses							10,487,000	12,360,000	6,328,000
Net Income (loss)							(6,863,000)	9,521,000	(2,503,000)
Depreciation and amortization expense							23,700,000	24,400,000	9,600,000
Net income before depreciation and amortization							16,845,000	33,878,000	7,144,000
Financial Position [Abstract]
Current assets							17,782,000	32,923,000
Noncurrent assets							265,584,000	264,997,000
Total assets							283,366,000	297,920,000
Current liabilities							23,034,000	22,497,000
Long term liabilities							67,598,000	75,826,000
Shareholders' equity							192,734,000	199,597,000
Total liabilities and equity							283,366,000	297,920,000
Equity in Income or Loss of AMAK Reflected on Consolidated Statement Of Operation [Abstract]
Company's share of earnings (loss) reported by AMAK	(2,419,000)	3,356,000	(885,000)
Amortization of difference between Company's investment in and Company's share of net assets of AMAKAMAK	1,347,000	1,347,000	674,000
Equity in earnings (loss) of AMAK	(1,072,000)	4,703,000	(211,000)
Increase in the entity's share in net assets of AMAK							4,000,000		8,900,000
Advances to AMAK	0	536,000					0	536,000
Proceeds from advances to AMAK					2,016,000
Additional advances to AMAK								$ 2,041,000