Condensed Consolidated Statements of Cash Flows (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2013
Operating activities:
Net income	$ 11,641	$ 11,094
Non-cash elements included in net income:
Depreciation, depletion and amortization	26,054	14,711
Loss (gain) on disposition of properties, plants, equipment, and mineral interests	275	(125)
Provision for reclamation and closure costs	933	591
Stock compensation	1,065	798
Deferred income taxes	(2,851)	3,990
Amortization of loan origination fees	519	135
Gain on derivative contracts	(8,847)	(19,620)
Foreign exchange gain	(4,688)
Other non-cash (gains) charges, net	4	(11)
Change in assets and liabilities:
Accounts receivable	1,387	4,708
Inventories	4,669	(5,108)
Other current and non-current assets	923	382
Accounts payable and accrued liabilities	(5,416)	(2,712)
Accrued payroll and related benefits	2,721	5,046
Accrued taxes	4,756	(2,497)
Accrued reclamation and closure costs and other non-current liabilities	(2,762)	(22)
Cash provided by operating activities	30,383	11,360
Investing activities:
Additions to properties, plants, equipment and mineral interests	(26,867)	(25,753)
Proceeds from disposition of properties, plants and equipment		126
Purchases of investments		(2,562)
Changes in restricted cash and investment balances	(2,485)	(12)
Net cash used in investing activities	(29,352)	(28,201)
Financing activities:
Acquisition of treasury shares		(286)
Dividends paid to common stockholders	(857)	(3,565)
Dividends paid to preferred stockholders	(138)	(138)
Debt origination fees	(468)
Repayments of capital leases	(2,403)	(1,540)
Net cash (used) provided by financing activities	(3,866)	(5,529)
Effect of exchange rates on cash	(1,698)
Net decrease in cash and cash equivalents	(4,533)	(22,370)
Cash and cash equivalents at beginning of period	212,175	190,984
Cash and cash equivalents at end of period	207,642	168,614
Significant non-cash investing and financing activities:
Addition of capital lease obligations	2,194	6,725
Increase to asset retirement obligations	8,210
Payment of accrued compensation in restricted stock units	$ 4,600