Condensed Consolidated Statements of Operations and Comprehensive Income (Loss) (Unaudited) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Sales of products	$ 135,507	$ 106,629	$ 378,796	$ 268,409
Cost of sales and other direct production costs	86,680	66,937	235,460	163,770
Depreciation, depletion and amortization	26,804	19,006	80,342	53,224
	113,484	85,943	315,802	216,994
Gross profit	22,023	20,686	62,994	51,415
Other operating expenses:
General and administrative	7,884	7,720	23,984	22,141
Exploration	5,797	5,797	13,086	18,511
Pre-development	391	3,444	1,247	12,747
Other operating expense	442	283	1,853	170
Provision (credit) for closed operations and reclamation	1,238	933	3,609	4,572
Aurizon acquisition costs		768		26,368
	15,752	18,945	43,779	84,509
Income (loss) from operations	6,271	1,741	19,215	(33,094)
Other income (expense):
Gain (loss) on derivative contracts	(411)	(4,564)	(2,560)	23,516
Gains on sale of investments				197
Unrealized loss on investments	(2,830)		(2,750)	327
Foreign exchange gain (loss)	7,299	(1,473)	6,051	(1,084)
Interest and other income	32	644	208	827
Interest expense, net of amount capitalized	(6,505)	(7,348)	(20,307)	(14,506)
	(2,415)	(12,741)	(19,358)	8,950
Income (loss) before income taxes	3,856	(11,000)	(143)	(24,144)
Income tax benefit (provision)	(180)	2,542	1,062	1,922
Net income (loss)	3,676	(8,458)	919	(22,222)
Preferred stock dividends	(138)	(138)	(414)	(414)
Income (loss) applicable to common shareholders	3,538	(8,596)	505	(22,636)
Net income (loss)	3,676	(8,458)	919	(22,222)
Reclassification of net gain on sale of marketable securities included in net income	2,425		2,425	(197)
Defined benefit pension plan costs		3,366	(1,192)	3,366
Unrealized holding gains (losses) on investments	(149)	(877)	205	(5,455)
Comprehensive income (loss)	$ 5,952	$ (5,969)	$ 2,357	$ (24,508)
Basic income (loss) per common share after preferred dividends (in Dollars per share)	$ 0.01	$ (0.03)	$ 0.00	$ (0.07)
Diluted income (loss) per common share after preferred dividends (in Dollars per share)	$ 0.01	$ (0.03)	$ 0.00	$ (0.07)
Weighted average number of common shares outstanding - basic (in Shares)	359,472	342,638	348,801	310,601
Weighted average number of common shares outstanding - diluted (in Shares)	362,262	342,638	354,673	310,601
Cash dividends declared per common share (in Dollars per share)	$ 0.0025	$ 0.0025	$ 0.0075	$ 0.0075